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FRC?","shockwave-curriculum\u002Flessons\u002Fch01-why-java-for-frc\u002F1.1-why-java-for-frc",{"path":9,"title":10,"stem":11},"\u002Fshockwave-curriculum\u002Flessons\u002Fch01-why-java-for-frc\u002F2-intro-to-algorithms-programming-and-compilers","Intro to Algorithms, Programming and Compilers","shockwave-curriculum\u002Flessons\u002Fch01-why-java-for-frc\u002F1.2-intro-to-algorithms-programming-and-compilers",{"path":13,"title":14,"stem":15},"\u002Fshockwave-curriculum\u002Flessons\u002Fch02-variables-and-types\u002F1-variables-and-data-types","Variables & Data Types","shockwave-curriculum\u002Flessons\u002Fch02-variables-and-types\u002F2.1-variables-and-data-types",{"path":17,"title":18,"stem":19},"\u002Fshockwave-curriculum\u002Flessons\u002Fch02-variables-and-types\u002F2-expressions-and-output","Expressions & Output","shockwave-curriculum\u002Flessons\u002Fch02-variables-and-types\u002F2.2-expressions-and-output",{"path":21,"title":22,"stem":23},"\u002Fshockwave-curriculum\u002Flessons\u002Fch02-variables-and-types\u002F3-assignment-and-input","Assignment & Input","shockwave-curriculum\u002Flessons\u002Fch02-variables-and-types\u002F2.3-assignment-and-input",{"path":25,"title":26,"stem":27},"\u002Fshockwave-curriculum\u002Flessons\u002Fch02-variables-and-types\u002F4-casting-and-ranges-of-values","Casting & Ranges of Values","shockwave-curriculum\u002Flessons\u002Fch02-variables-and-types\u002F2.4-casting-and-ranges-of-values",{"path":29,"title":30,"stem":31},"\u002Fshockwave-curriculum\u002Flessons\u002Fch02-variables-and-types\u002F5-compound-assignment-operators","Compound Assignment Operators","shockwave-curriculum\u002Flessons\u002Fch02-variables-and-types\u002F2.5-compound-assignment-operators",{"path":33,"title":34,"stem":35},"\u002Fshockwave-curriculum\u002Flessons\u002Fch03-apis-libraries-and-documentation\u002F1-apis-and-libraries","APIs and Libraries","shockwave-curriculum\u002Flessons\u002Fch03-apis-libraries-and-documentation\u002F3.1-apis-and-libraries",{"path":37,"title":38,"stem":39},"\u002Fshockwave-curriculum\u002Flessons\u002Fch03-apis-libraries-and-documentation\u002F2-documentation-with-comments-and-preconditions","Documentation with Comments and Preconditions","shockwave-curriculum\u002Flessons\u002Fch03-apis-libraries-and-documentation\u002F3.2-documentation-with-comments-and-preconditions",{"path":41,"title":42,"stem":43},"\u002Fshockwave-curriculum\u002Flessons\u002Fch03-apis-libraries-and-documentation\u002F3-packages-and-imports","Packages & Imports","shockwave-curriculum\u002Flessons\u002Fch03-apis-libraries-and-documentation\u002F3.3-packages-and-imports",{"path":45,"title":46,"stem":47},"\u002Fshockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F1-methods-signatures-and-parameters","Methods, Signatures & Parameters","shockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F4.1-methods-signatures-and-parameters",{"path":49,"title":50,"stem":51},"\u002Fshockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F2-calling-class-methods","Calling Class Methods","shockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F4.2-calling-class-methods",{"path":53,"title":54,"stem":55},"\u002Fshockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F3-using-the-math-class","Using the Math Class","shockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F4.3-using-the-math-class",{"path":57,"title":58,"stem":59},"\u002Fshockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F4-objects-instances-of-classes","Objects — Instances of Classes","shockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F4.4-objects-instances-of-classes",{"path":61,"title":62,"stem":63},"\u002Fshockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F5-creating-and-initializing-objects-constructors","Creating & Initializing Objects: Constructors","shockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F4.5-creating-and-initializing-objects-constructors",{"path":65,"title":66,"stem":67},"\u002Fshockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F6-calling-instance-methods","Calling Instance Methods","shockwave-curriculum\u002Flessons\u002Fch04-using-objects-and-calling-methods\u002F4.6-calling-instance-methods",{"path":69,"title":70,"stem":71},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F1-5.2-if-statements-and-for-loops","Control Structures: if Statements & For Loops","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.1-5.2-if-statements-and-for-loops",{"path":73,"title":74,"stem":75},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F10-nested-iteration","Nested Iteration","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.10-nested-iteration",{"path":77,"title":78,"stem":79},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F11-informal-runtime-analysis-of-loops","Informal Runtime Analysis of Loops","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.11-informal-runtime-analysis-of-loops",{"path":81,"title":82,"stem":83},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F12-switch-statements-and-expressions","switch Statements and Expressions","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.12-switch-statements-and-expressions",{"path":85,"title":86,"stem":87},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F3-algorithms-with-selection-and-repetition","Algorithms with Selection and Repetition","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.3-algorithms-with-selection-and-repetition",{"path":89,"title":90,"stem":91},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F4-boolean-expressions","Boolean Expressions","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.4-boolean-expressions",{"path":93,"title":94,"stem":95},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5-nested-if-statements","Nested if Statements","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.5-nested-if-statements",{"path":97,"title":98,"stem":99},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F6-compound-boolean-expressions","Compound Boolean Expressions","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.6-compound-boolean-expressions",{"path":101,"title":102,"stem":103},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F7-comparing-boolean-expressions-de-morgans-laws","Comparing Boolean Expressions (De Morgan's Laws)","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.7-comparing-boolean-expressions-de-morgans-laws",{"path":105,"title":106,"stem":107},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F8-while-loops","While Loops","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.8-while-loops",{"path":109,"title":110,"stem":111},"\u002Fshockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F9-implementing-selection-and-iteration-algorithms","Implementing Selection and Iteration Algorithms","shockwave-curriculum\u002Flessons\u002Fch05-control-structures\u002F5.9-implementing-selection-and-iteration-algorithms",{"path":113,"title":114,"stem":115},"\u002Fshockwave-curriculum\u002Flessons\u002Fch06-strings\u002F1-strings","Strings","shockwave-curriculum\u002Flessons\u002Fch06-strings\u002F6.1-strings",{"path":117,"title":118,"stem":119},"\u002Fshockwave-curriculum\u002Flessons\u002Fch06-strings\u002F2-string-algorithms","String Algorithms","shockwave-curriculum\u002Flessons\u002Fch06-strings\u002F6.2-string-algorithms",{"path":121,"title":122,"stem":123},"\u002Fshockwave-curriculum\u002Flessons\u002Fch07-the-class-blueprint\u002F1-anatomy-of-a-java-class","The Class Blueprint","shockwave-curriculum\u002Flessons\u002Fch07-the-class-blueprint\u002F7.1-anatomy-of-a-java-class",{"path":125,"title":126,"stem":127},"\u002Fshockwave-curriculum\u002Flessons\u002Fch07-the-class-blueprint\u002F2-methods-how-to-write-them","Methods: How to Write Them","shockwave-curriculum\u002Flessons\u002Fch07-the-class-blueprint\u002F7.2-methods-how-to-write-them",{"path":129,"title":130,"stem":131},"\u002Fshockwave-curriculum\u002Flessons\u002Fch07-the-class-blueprint\u002F3-methods-passing-and-returning-references-of-an-object","Methods: Passing & Returning References of an Object","shockwave-curriculum\u002Flessons\u002Fch07-the-class-blueprint\u002F7.3-methods-passing-and-returning-references-of-an-object",{"path":133,"title":134,"stem":135},"\u002Fshockwave-curriculum\u002Flessons\u002Fch07-the-class-blueprint\u002F4-class-static-variables-and-methods","Class (static) Variables & Methods","shockwave-curriculum\u002Flessons\u002Fch07-the-class-blueprint\u002F7.4-class-static-variables-and-methods",{"path":137,"title":138,"stem":139},"\u002Fshockwave-curriculum\u002Flessons\u002Fch08-constructors-and-this\u002F1-8.2-constructors-and-this","Constructors & \"this\"","shockwave-curriculum\u002Flessons\u002Fch08-constructors-and-this\u002F8.1-8.2-constructors-and-this",{"path":141,"title":142,"stem":143},"\u002Fshockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F1-array-creation-and-access","Array Creation and Access","shockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F9.1-array-creation-and-access",{"path":145,"title":146,"stem":147},"\u002Fshockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F2-arraylist-and-its-methods","ArrayList and its Methods","shockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F9.2-arraylist-and-its-methods",{"path":149,"title":150,"stem":151},"\u002Fshockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F3-optional-hashmap-dictionary-data-structure","HashMap (Dictionary) Data Structure","shockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F9.3-optional-hashmap-dictionary-data-structure",{"path":153,"title":154,"stem":155},"\u002Fshockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F4-array-traversals","Array Traversals","shockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F9.4-array-traversals",{"path":157,"title":158,"stem":159},"\u002Fshockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F5-implementing-array-algorithms","Implementing Array Algorithms","shockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F9.5-implementing-array-algorithms",{"path":161,"title":162,"stem":163},"\u002Fshockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F6-arraylist-traversals","ArrayList Traversals","shockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F9.6-arraylist-traversals",{"path":165,"title":166,"stem":167},"\u002Fshockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F7-implementing-arraylist-algorithms","Implementing ArrayList Algorithms","shockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F9.7-implementing-arraylist-algorithms",{"path":169,"title":170,"stem":171},"\u002Fshockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F8-using-text-files","Using Text Files","shockwave-curriculum\u002Flessons\u002Fch09-storing-data\u002F9.8-using-text-files",{"path":173,"title":174,"stem":175},"\u002Fshockwave-curriculum\u002Flessons\u002Fch10-2d-arrays\u002F1-2d-array-creation-and-access","2D Array Creation and Access","shockwave-curriculum\u002Flessons\u002Fch10-2d-arrays\u002F10.1-2d-array-creation-and-access",{"path":177,"title":178,"stem":179},"\u002Fshockwave-curriculum\u002Flessons\u002Fch10-2d-arrays\u002F2-2d-array-traversals-nested-loops","2D Array Traversals: Nested Loops","shockwave-curriculum\u002Flessons\u002Fch10-2d-arrays\u002F10.2-2d-array-traversals-nested-loops",{"path":181,"title":182,"stem":183},"\u002Fshockwave-curriculum\u002Flessons\u002Fch10-2d-arrays\u002F3-implementing-2d-array-algorithms","Implementing 2D Array Algorithms","shockwave-curriculum\u002Flessons\u002Fch10-2d-arrays\u002F10.3-implementing-2d-array-algorithms",{"path":185,"title":186,"stem":187},"\u002Fshockwave-curriculum\u002Flessons\u002Fch11-enums-named-choices\u002F11-enums-named-choices","Enums: Named Choices","shockwave-curriculum\u002Flessons\u002Fch11-enums-named-choices\u002F11-enums-named-choices",{"path":189,"title":190,"stem":191},"\u002Fshockwave-curriculum\u002Flessons\u002Fch12-exceptions-and-try-catch\u002F12-exceptions-and-try-catch","Exceptions & try\u002Fcatch","shockwave-curriculum\u002Flessons\u002Fch12-exceptions-and-try-catch\u002F12-exceptions-and-try-catch",{"path":193,"title":194,"stem":195},"\u002Fshockwave-curriculum\u002Flessons\u002Fch13-common-gotchas\u002F13-common-gotchas","Common Gotchas","shockwave-curriculum\u002Flessons\u002Fch13-common-gotchas\u002F13-common-gotchas",{"path":197,"title":198,"stem":199},"\u002Fshockwave-curriculum\u002Flessons\u002Fch14-why-design-patterns\u002F14-why-design-patterns","Why Design Patterns?","shockwave-curriculum\u002Flessons\u002Fch14-why-design-patterns\u002F14-why-design-patterns",{"path":201,"title":202,"stem":203},"\u002Fshockwave-curriculum\u002Flessons\u002Fch15-advanced-collections\u002F15-advanced-collections","Advanced Collections (Set\u002FQueue\u002FMap)","shockwave-curriculum\u002Flessons\u002Fch15-advanced-collections\u002F15-advanced-collections",{"path":205,"title":206,"stem":207},"\u002Fshockwave-curriculum\u002Flessons\u002Fch16-writing-your-own-generics\u002F16-writing-your-own-generics","Writing Your Own Generics","shockwave-curriculum\u002Flessons\u002Fch16-writing-your-own-generics\u002F16-writing-your-own-generics",{"path":209,"title":210,"stem":211},"\u002Fshockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F1-inheritance-superclass-subclass","Inheritance, Superclass, Subclass","shockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F17.1-inheritance-superclass-subclass",{"path":213,"title":214,"stem":215},"\u002Fshockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F2-inheritance-and-constructors","Inheritance and Constructors","shockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F17.2-inheritance-and-constructors",{"path":217,"title":218,"stem":219},"\u002Fshockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F3-inheritance-hierarchies","Inheritance Hierarchies","shockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F17.3-inheritance-hierarchies",{"path":221,"title":222,"stem":223},"\u002Fshockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F4-object-superclass","Object Superclass","shockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F17.4-object-superclass",{"path":225,"title":226,"stem":227},"\u002Fshockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F5-abstract-classes-and-methods","Abstract Classes and Methods","shockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F17.5-abstract-classes-and-methods",{"path":229,"title":230,"stem":231},"\u002Fshockwave-curriculum\u002Flessons\u002Fch18-polymorphism-many-forms\u002F1-overriding-methods","Overriding Methods","shockwave-curriculum\u002Flessons\u002Fch18-polymorphism-many-forms\u002F18.1-overriding-methods",{"path":233,"title":234,"stem":235},"\u002Fshockwave-curriculum\u002Flessons\u002Fch18-polymorphism-many-forms\u002F2-super-keyword","super Keyword","shockwave-curriculum\u002Flessons\u002Fch18-polymorphism-many-forms\u002F18.2-super-keyword",{"path":237,"title":238,"stem":239},"\u002Fshockwave-curriculum\u002Flessons\u002Fch18-polymorphism-many-forms\u002F3-polymorphism","Polymorphism","shockwave-curriculum\u002Flessons\u002Fch18-polymorphism-many-forms\u002F18.3-polymorphism",{"path":241,"title":242,"stem":243},"\u002Fshockwave-curriculum\u002Flessons\u002Fch19-interfaces-as-contracts\u002F19-interfaces-as-contracts","Interfaces as Contracts","shockwave-curriculum\u002Flessons\u002Fch19-interfaces-as-contracts\u002F19-interfaces-as-contracts",{"path":245,"title":246,"stem":247},"\u002Fshockwave-curriculum\u002Flessons\u002Fch19-interfaces-as-contracts\u002F1-lambdas-and-method-references","Lambdas & Method References","shockwave-curriculum\u002Flessons\u002Fch19-interfaces-as-contracts\u002F19.1-lambdas-and-method-references",{"path":249,"title":250,"stem":251},"\u002Fshockwave-curriculum\u002Flessons\u002Fch20-the-io-layer-pattern\u002F20-the-io-layer-pattern","The IO-Layer Pattern","shockwave-curriculum\u002Flessons\u002Fch20-the-io-layer-pattern\u002F20-the-io-layer-pattern",{"path":253,"title":254,"stem":255},"\u002Fshockwave-curriculum\u002Flessons\u002Fch21-static-factories\u002F21-static-factories","Static Factories","shockwave-curriculum\u002Flessons\u002Fch21-static-factories\u002F21-static-factories",{"path":257,"title":258,"stem":259},"\u002Fshockwave-curriculum\u002Flessons\u002Fch22-the-builder-pattern\u002F22-the-builder-pattern","The Builder Pattern","shockwave-curriculum\u002Flessons\u002Fch22-the-builder-pattern\u002F22-the-builder-pattern",{"path":261,"title":262,"stem":263},"\u002Fshockwave-curriculum\u002Flessons\u002Fch23-encapsulation-and-final\u002F1-scope-and-access","Access, final, and Immutability","shockwave-curriculum\u002Flessons\u002Fch23-encapsulation-and-final\u002F23.1-scope-and-access",{"path":265,"title":266,"stem":267},"\u002Fshockwave-curriculum\u002Flessons\u002Fch24-optional-avoiding-null-pointer-exceptions\u002F24-optional-avoiding-null-pointer-exceptions","Optional: Avoiding Null Pointer Exceptions","shockwave-curriculum\u002Flessons\u002Fch24-optional-avoiding-null-pointer-exceptions\u002F24-optional-avoiding-null-pointer-exceptions",{"path":269,"title":270,"stem":271},"\u002Fshockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F1-what-is-command-based-programming","What Is Command-Based Programming?","shockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F25.1-what-is-command-based-programming",{"path":273,"title":274,"stem":275},"\u002Fshockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F2-commands-and-command-compositions","Commands & Command Compositions","shockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F25.2-commands-and-command-compositions",{"path":277,"title":278,"stem":279},"\u002Fshockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F3-the-command-scheduler","The Command Scheduler","shockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F25.3-the-command-scheduler",{"path":281,"title":282,"stem":283},"\u002Fshockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F4-state-machines-logic","State Machines: Logic","shockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F25.4-state-machines-logic",{"path":285,"title":286,"stem":287},"\u002Fshockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F5-managing-transitions","Managing Transitions","shockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F25.5-managing-transitions",{"path":289,"title":290,"stem":291},"\u002Fshockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F6-binding-commands-to-triggers","Binding Commands to Triggers","shockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F25.6-binding-commands-to-triggers",{"path":293,"title":294,"stem":295},"\u002Fshockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F7-structuring-a-command-based-robot-project","Structuring a Command-Based Robot Project","shockwave-curriculum\u002Flessons\u002Fch25-command-based-programming\u002F25.7-structuring-a-command-based-robot-project",{"path":297,"title":298,"stem":299},"\u002Fshockwave-curriculum\u002Flessons\u002Fch26-architecture-takeaways\u002F26-architecture-takeaways","Architecture Takeaways","shockwave-curriculum\u002Flessons\u002Fch26-architecture-takeaways\u002F26-architecture-takeaways",{"path":301,"title":302,"stem":303},"\u002Fshockwave-curriculum\u002Flessons\u002Fch27-program-design-and-abstraction\u002F1-abstraction-and-program-design","Abstraction and Program Design","shockwave-curriculum\u002Flessons\u002Fch27-program-design-and-abstraction\u002F27.1-abstraction-and-program-design",{"path":305,"title":306,"stem":307},"\u002Fshockwave-curriculum\u002Flessons\u002Fch27-program-design-and-abstraction\u002F2-impact-of-program-design","Impact of Program Design","shockwave-curriculum\u002Flessons\u002Fch27-program-design-and-abstraction\u002F27.2-impact-of-program-design",{"path":309,"title":310,"stem":311},"\u002Fshockwave-curriculum\u002Flessons\u002Fch28-algorithms-searching-sorting-recursion\u002F1-searching-algorithms","Searching Algorithms","shockwave-curriculum\u002Flessons\u002Fch28-algorithms-searching-sorting-recursion\u002F28.1-searching-algorithms",{"path":313,"title":314,"stem":315},"\u002Fshockwave-curriculum\u002Flessons\u002Fch28-algorithms-searching-sorting-recursion\u002F2-sorting-algorithms","Sorting Algorithms","shockwave-curriculum\u002Flessons\u002Fch28-algorithms-searching-sorting-recursion\u002F28.2-sorting-algorithms",{"path":317,"title":318,"stem":319},"\u002Fshockwave-curriculum\u002Flessons\u002Fch28-algorithms-searching-sorting-recursion\u002F3-recursion","Recursion","shockwave-curriculum\u002Flessons\u002Fch28-algorithms-searching-sorting-recursion\u002F28.3-recursion",{"path":321,"title":322,"stem":323},"\u002Fshockwave-curriculum\u002Flessons\u002Fch28-algorithms-searching-sorting-recursion\u002F4-recursive-searching-and-sorting","Recursive Searching and Sorting","shockwave-curriculum\u002Flessons\u002Fch28-algorithms-searching-sorting-recursion\u002F28.4-recursive-searching-and-sorting",{"path":325,"title":326,"stem":327},"\u002Fshockwave-curriculum\u002Flessons\u002Fch29-git-and-github-basics\u002F1-coming-soon","Git & GitHub Basics — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch29-git-and-github-basics\u002F29.1-coming-soon",{"path":329,"title":330,"stem":331},"\u002Fshockwave-curriculum\u002Flessons\u002Fch30-git-history-and-merging\u002F1-coming-soon","Git — History & Merging — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch30-git-history-and-merging\u002F30.1-coming-soon",{"path":333,"title":334,"stem":335},"\u002Fshockwave-curriculum\u002Flessons\u002Fch31-dev-environment-and-tooling\u002F1-coming-soon","Dev Environment & Tooling — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch31-dev-environment-and-tooling\u002F31.1-coming-soon",{"path":337,"title":338,"stem":339},"\u002Fshockwave-curriculum\u002Flessons\u002Fch32-unit-testing\u002F1-coming-soon","Unit Testing — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch32-unit-testing\u002F32.1-coming-soon",{"path":341,"title":342,"stem":343},"\u002Fshockwave-curriculum\u002Flessons\u002Fch33-advantagekit-autologging\u002F1-coming-soon","AdvantageKit — AutoLogging — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch33-advantagekit-autologging\u002F33.1-coming-soon",{"path":345,"title":346,"stem":347},"\u002Fshockwave-curriculum\u002Flessons\u002Fch34-log-replay\u002F1-coming-soon","Log Replay — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch34-log-replay\u002F34.1-coming-soon",{"path":349,"title":350,"stem":351},"\u002Fshockwave-curriculum\u002Flessons\u002Fch35-advantagescope-i-visualization\u002F1-coming-soon","AdvantageScope I: Visualization — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch35-advantagescope-i-visualization\u002F35.1-coming-soon",{"path":353,"title":354,"stem":355},"\u002Fshockwave-curriculum\u002Flessons\u002Fch36-advantagescope-ii-custom-3d-assets\u002F1-coming-soon","AdvantageScope II: Custom 3D Assets — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch36-advantagescope-ii-custom-3d-assets\u002F36.1-coming-soon",{"path":357,"title":358,"stem":359},"\u002Fshockwave-curriculum\u002Flessons\u002Fch37-autonomous-i\u002F1-coming-soon","Autonomous I — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch37-autonomous-i\u002F37.1-coming-soon",{"path":361,"title":362,"stem":363},"\u002Fshockwave-curriculum\u002Flessons\u002Fch38-autonomous-ii-pathplanner-and-trajectories\u002F1-coming-soon","Autonomous II: PathPlanner & Trajectories — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch38-autonomous-ii-pathplanner-and-trajectories\u002F38.1-coming-soon",{"path":365,"title":366,"stem":367},"\u002Fshockwave-curriculum\u002Flessons\u002Fch39-control-fundamentals\u002F1-coming-soon","Control Fundamentals — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch39-control-fundamentals\u002F39.1-coming-soon",{"path":369,"title":370,"stem":371},"\u002Fshockwave-curriculum\u002Flessons\u002Fch40-motion-profiles\u002F1-coming-soon","Motion Profiles — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch40-motion-profiles\u002F40.1-coming-soon",{"path":373,"title":374,"stem":375},"\u002Fshockwave-curriculum\u002Flessons\u002Fch41-hardware-fundamentals\u002F1-coming-soon","Hardware Fundamentals — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch41-hardware-fundamentals\u002F41.1-coming-soon",{"path":377,"title":378,"stem":379},"\u002Fshockwave-curriculum\u002Flessons\u002Fch42-photonvision\u002F1-coming-soon","PhotonVision — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch42-photonvision\u002F42.1-coming-soon",{"path":381,"title":382,"stem":383},"\u002Fshockwave-curriculum\u002Flessons\u002Fch43-apriltags-and-pose\u002F1-coming-soon","AprilTags & Pose — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch43-apriltags-and-pose\u002F43.1-coming-soon",{"path":385,"title":386,"stem":387},"\u002Fshockwave-curriculum\u002Flessons\u002Fch44-subsystems-i\u002F1-coming-soon","Subsystems I — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch44-subsystems-i\u002F44.1-coming-soon",{"path":389,"title":390,"stem":391},"\u002Fshockwave-curriculum\u002Flessons\u002Fch45-subsystems-ii-advanced\u002F1-coming-soon","Subsystems II — Advanced — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch45-subsystems-ii-advanced\u002F45.1-coming-soon",{"path":393,"title":394,"stem":395},"\u002Fshockwave-curriculum\u002Flessons\u002Fch46-team-utilities-i\u002F1-coming-soon","Team Utilities I — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch46-team-utilities-i\u002F46.1-coming-soon",{"path":397,"title":398,"stem":399},"\u002Fshockwave-curriculum\u002Flessons\u002Fch47-field-constants\u002F1-coming-soon","Field Constants — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch47-field-constants\u002F47.1-coming-soon",{"path":401,"title":402,"stem":403},"\u002Fshockwave-curriculum\u002Flessons\u002Fch48-troubleshooting-i-runtime-debug\u002F1-coming-soon","Troubleshooting I — Runtime Debug — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch48-troubleshooting-i-runtime-debug\u002F48.1-coming-soon",{"path":405,"title":406,"stem":407},"\u002Fshockwave-curriculum\u002Flessons\u002Fch49-troubleshooting-ii-can-and-sim\u002F1-coming-soon","Troubleshooting II: CAN & Sim — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch49-troubleshooting-ii-can-and-sim\u002F49.1-coming-soon",{"path":409,"title":410,"stem":411},"\u002Fshockwave-curriculum\u002Flessons\u002Fch50-vendor-libraries-talonfx\u002F1-coming-soon","Vendor Libraries: TalonFX — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch50-vendor-libraries-talonfx\u002F50.1-coming-soon",{"path":413,"title":414,"stem":415},"\u002Fshockwave-curriculum\u002Flessons\u002Fch51-robot-alerts\u002F1-coming-soon","Robot Alerts — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch51-robot-alerts\u002F51.1-coming-soon",{"path":417,"title":418,"stem":419},"\u002Fshockwave-curriculum\u002Flessons\u002Fch52-wpilib-commands\u002F1-coming-soon","WPILib Commands — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch52-wpilib-commands\u002F52.1-coming-soon",{"path":421,"title":422,"stem":423},"\u002Fshockwave-curriculum\u002Flessons\u002Fch53-wpilib-geometry\u002F1-coming-soon","WPILib Geometry — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch53-wpilib-geometry\u002F53.1-coming-soon",{"path":425,"title":426,"stem":427},"\u002Fshockwave-curriculum\u002Flessons\u002Fch54-networktables\u002F1-coming-soon","NetworkTables — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch54-networktables\u002F54.1-coming-soon",{"path":429,"title":430,"stem":431},"\u002Fshockwave-curriculum\u002Flessons\u002Fch55-command-scheduler\u002F1-coming-soon","Command Scheduler — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch55-command-scheduler\u002F55.1-coming-soon",{"path":433,"title":434,"stem":435},"\u002Fshockwave-curriculum\u002Flessons\u002Fch56-wpilib-timers\u002F1-coming-soon","WPILib Timers — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch56-wpilib-timers\u002F56.1-coming-soon",{"path":437,"title":438,"stem":439},"\u002Fshockwave-curriculum\u002Flessons\u002Fch57-wpilib-triggers\u002F1-coming-soon","WPILib Triggers — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch57-wpilib-triggers\u002F57.1-coming-soon",{"path":441,"title":442,"stem":443},"\u002Fshockwave-curriculum\u002Flessons\u002Fch58-vendor-units-and-conversions\u002F1-coming-soon","Vendor Units & Conversions — Coming Soon","shockwave-curriculum\u002Flessons\u002Fch58-vendor-units-and-conversions\u002F58.1-coming-soon",[445,449,453,457,461,465,469,473,477,481,485,489,493,497,501,505,509,513,517,521,525,529,533,537,541,545,549,553,557,561,565,569,573,577,581,585,589,593,597,601,605,609,613,617,621,625,629,633,637,641,645,649,653,657,661,665,669,673,677,681,685,689,693,697,701,705,709,713,717,721,725,729,733,737,741,745,749],{"path":446,"title":447,"stem":448},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch01-why-java-for-frc\u002F2-intro-to-algorithms-programming-and-compilers","Intro to Algorithms, Programming and Compilers — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch01-why-java-for-frc\u002F1.2-intro-to-algorithms-programming-and-compilers",{"path":450,"title":451,"stem":452},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch02-variables-and-types\u002F1-variables-and-data-types","Variables & Data Types — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch02-variables-and-types\u002F2.1-variables-and-data-types",{"path":454,"title":455,"stem":456},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch02-variables-and-types\u002F2-expressions-and-output","Expressions & Output — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch02-variables-and-types\u002F2.2-expressions-and-output",{"path":458,"title":459,"stem":460},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch02-variables-and-types\u002F3-assignment-and-input","Assignment & Input — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch02-variables-and-types\u002F2.3-assignment-and-input",{"path":462,"title":463,"stem":464},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch02-variables-and-types\u002F4-casting-and-ranges-of-values","Casting & Ranges of Values — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch02-variables-and-types\u002F2.4-casting-and-ranges-of-values",{"path":466,"title":467,"stem":468},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch02-variables-and-types\u002F5-compound-assignment-operators","Compound Assignment Operators — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch02-variables-and-types\u002F2.5-compound-assignment-operators",{"path":470,"title":471,"stem":472},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch03-apis-libraries-and-documentation\u002F1-apis-and-libraries","APIs and Libraries — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch03-apis-libraries-and-documentation\u002F3.1-apis-and-libraries",{"path":474,"title":475,"stem":476},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch03-apis-libraries-and-documentation\u002F2-documentation-with-comments-and-preconditions","Documentation with Comments and Preconditions — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch03-apis-libraries-and-documentation\u002F3.2-documentation-with-comments-and-preconditions",{"path":478,"title":479,"stem":480},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch03-apis-libraries-and-documentation\u002F3-packages-and-imports","Packages & Imports — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch03-apis-libraries-and-documentation\u002F3.3-packages-and-imports",{"path":482,"title":483,"stem":484},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F1-methods-signatures-and-parameters","Methods, Signatures & Parameters — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F4.1-methods-signatures-and-parameters",{"path":486,"title":487,"stem":488},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F2-calling-class-methods","Calling Class Methods — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F4.2-calling-class-methods",{"path":490,"title":491,"stem":492},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F3-using-the-math-class","Using the Math Class — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F4.3-using-the-math-class",{"path":494,"title":495,"stem":496},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F4-objects-instances-of-classes","Objects — Instances of Classes — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F4.4-objects-instances-of-classes",{"path":498,"title":499,"stem":500},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F5-creating-and-initializing-objects-constructors","Creating & Initializing Objects: Constructors — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F4.5-creating-and-initializing-objects-constructors",{"path":502,"title":503,"stem":504},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F6-calling-instance-methods","Calling Instance Methods — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch04-using-objects-and-calling-methods\u002F4.6-calling-instance-methods",{"path":506,"title":507,"stem":508},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F1-5.2-if-statements-and-for-loops","if Statements & For Loops — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.1-5.2-if-statements-and-for-loops",{"path":510,"title":511,"stem":512},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F10-nested-iteration","Nested Iteration — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.10-nested-iteration",{"path":514,"title":515,"stem":516},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F11-informal-runtime-analysis-of-loops","Informal Runtime Analysis of Loops — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.11-informal-runtime-analysis-of-loops",{"path":518,"title":519,"stem":520},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F12-switch-statements-and-expressions","switch Statements and Expressions — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.12-switch-statements-and-expressions",{"path":522,"title":523,"stem":524},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F3-algorithms-with-selection-and-repetition","Algorithms with Selection and Repetition — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.3-algorithms-with-selection-and-repetition",{"path":526,"title":527,"stem":528},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F4-boolean-expressions","Boolean Expressions — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.4-boolean-expressions",{"path":530,"title":531,"stem":532},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5-nested-if-statements","Nested if Statements — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.5-nested-if-statements",{"path":534,"title":535,"stem":536},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F6-compound-boolean-expressions","Compound Boolean Expressions — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.6-compound-boolean-expressions",{"path":538,"title":539,"stem":540},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F7-comparing-boolean-expressions-de-morgans-laws","Comparing Boolean Expressions (De Morgan's Laws) — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.7-comparing-boolean-expressions-de-morgans-laws",{"path":542,"title":543,"stem":544},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F8-while-loops","While Loops — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.8-while-loops",{"path":546,"title":547,"stem":548},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F9-implementing-selection-and-iteration-algorithms","Implementing Selection and Iteration Algorithms — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch05-control-structures\u002F5.9-implementing-selection-and-iteration-algorithms",{"path":550,"title":551,"stem":552},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch06-strings\u002F1-strings","Strings — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch06-strings\u002F6.1-strings",{"path":554,"title":555,"stem":556},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch06-strings\u002F2-string-algorithms","String Algorithms — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch06-strings\u002F6.2-string-algorithms",{"path":558,"title":559,"stem":560},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch07-the-class-blueprint\u002F1-anatomy-of-a-java-class","Anatomy of a Java Class — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch07-the-class-blueprint\u002F7.1-anatomy-of-a-java-class",{"path":562,"title":563,"stem":564},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch07-the-class-blueprint\u002F2-methods-how-to-write-them","Methods: How to Write Them — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch07-the-class-blueprint\u002F7.2-methods-how-to-write-them",{"path":566,"title":567,"stem":568},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch07-the-class-blueprint\u002F3-methods-passing-and-returning-references-of-an-object","Methods: Passing & Returning References of an Object — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch07-the-class-blueprint\u002F7.3-methods-passing-and-returning-references-of-an-object",{"path":570,"title":571,"stem":572},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch07-the-class-blueprint\u002F4-class-static-variables-and-methods","Class (static) Variables & Methods — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch07-the-class-blueprint\u002F7.4-class-static-variables-and-methods",{"path":574,"title":575,"stem":576},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch08-constructors-and-this\u002F1-8.2-constructors-and-this","Constructors & \"this\" — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch08-constructors-and-this\u002F8.1-8.2-constructors-and-this",{"path":578,"title":579,"stem":580},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F1-array-creation-and-access","Array Creation and Access — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F9.1-array-creation-and-access",{"path":582,"title":583,"stem":584},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F2-arraylist-and-its-methods","ArrayList and its Methods — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F9.2-arraylist-and-its-methods",{"path":586,"title":587,"stem":588},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F3-optional-hashmap-dictionary-data-structure","HashMap (Dictionary) Data Structure — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F9.3-optional-hashmap-dictionary-data-structure",{"path":590,"title":591,"stem":592},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F4-array-traversals","Array Traversals — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F9.4-array-traversals",{"path":594,"title":595,"stem":596},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F5-implementing-array-algorithms","Implementing Array Algorithms — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F9.5-implementing-array-algorithms",{"path":598,"title":599,"stem":600},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F6-arraylist-traversals","ArrayList Traversals — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F9.6-arraylist-traversals",{"path":602,"title":603,"stem":604},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F7-implementing-arraylist-algorithms","Implementing ArrayList Algorithms — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F9.7-implementing-arraylist-algorithms",{"path":606,"title":607,"stem":608},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F8-using-text-files","Using Text Files — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch09-storing-data\u002F9.8-using-text-files",{"path":610,"title":611,"stem":612},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch10-2d-arrays\u002F1-2d-array-creation-and-access","2D Array Creation and Access — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch10-2d-arrays\u002F10.1-2d-array-creation-and-access",{"path":614,"title":615,"stem":616},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch10-2d-arrays\u002F2-2d-array-traversals-nested-loops","2D Array Traversals: Nested Loops — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch10-2d-arrays\u002F10.2-2d-array-traversals-nested-loops",{"path":618,"title":619,"stem":620},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch10-2d-arrays\u002F3-implementing-2d-array-algorithms","Implementing 2D Array Algorithms — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch10-2d-arrays\u002F10.3-implementing-2d-array-algorithms",{"path":622,"title":623,"stem":624},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch11-enums-named-choices\u002F11-enums-named-choices","Enums: Named Choices — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch11-enums-named-choices\u002F11-enums-named-choices",{"path":626,"title":627,"stem":628},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch12-exceptions-and-try-catch\u002F12-exceptions-and-try-catch","Exceptions & try\u002Fcatch — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch12-exceptions-and-try-catch\u002F12-exceptions-and-try-catch",{"path":630,"title":631,"stem":632},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch13-common-gotchas\u002F13-common-gotchas","Common Gotchas — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch13-common-gotchas\u002F13-common-gotchas",{"path":634,"title":635,"stem":636},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch15-advanced-collections\u002F15-advanced-collections","Advanced Collections (Set\u002FQueue\u002FMap) — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch15-advanced-collections\u002F15-advanced-collections",{"path":638,"title":639,"stem":640},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch16-writing-your-own-generics\u002F16-writing-your-own-generics","Writing Your Own Generics — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch16-writing-your-own-generics\u002F16-writing-your-own-generics",{"path":642,"title":643,"stem":644},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F1-inheritance-superclass-subclass","Inheritance, Superclass, Subclass — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F17.1-inheritance-superclass-subclass",{"path":646,"title":647,"stem":648},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F2-inheritance-and-constructors","Inheritance and Constructors — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F17.2-inheritance-and-constructors",{"path":650,"title":651,"stem":652},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F3-inheritance-hierarchies","Inheritance Hierarchies — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F17.3-inheritance-hierarchies",{"path":654,"title":655,"stem":656},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F4-object-superclass","Object Superclass — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F17.4-object-superclass",{"path":658,"title":659,"stem":660},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F5-abstract-classes-and-methods","Abstract Classes and Methods — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F17.5-abstract-classes-and-methods",{"path":662,"title":663,"stem":664},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch18-polymorphism-many-forms\u002F1-overriding-methods","Overriding Methods — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch18-polymorphism-many-forms\u002F18.1-overriding-methods",{"path":666,"title":667,"stem":668},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch18-polymorphism-many-forms\u002F2-super-keyword","super Keyword — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch18-polymorphism-many-forms\u002F18.2-super-keyword",{"path":670,"title":671,"stem":672},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch18-polymorphism-many-forms\u002F3-polymorphism","Polymorphism — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch18-polymorphism-many-forms\u002F18.3-polymorphism",{"path":674,"title":675,"stem":676},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch19-interfaces-as-contracts\u002F19-interfaces-as-contracts","Interfaces as Contracts — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch19-interfaces-as-contracts\u002F19-interfaces-as-contracts",{"path":678,"title":679,"stem":680},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch19-interfaces-as-contracts\u002F1-lambdas-and-method-references","Lambdas & Method References — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch19-interfaces-as-contracts\u002F19.1-lambdas-and-method-references",{"path":682,"title":683,"stem":684},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch20-the-io-layer-pattern\u002F20-the-io-layer-pattern","The IO-Layer Pattern — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch20-the-io-layer-pattern\u002F20-the-io-layer-pattern",{"path":686,"title":687,"stem":688},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch21-static-factories\u002F21-static-factories","Static Factories — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch21-static-factories\u002F21-static-factories",{"path":690,"title":691,"stem":692},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch22-the-builder-pattern\u002F22-the-builder-pattern","The Builder Pattern — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch22-the-builder-pattern\u002F22-the-builder-pattern",{"path":694,"title":695,"stem":696},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch23-encapsulation-and-final\u002F1-scope-and-access","Access, final, and Immutability — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch23-encapsulation-and-final\u002F23.1-scope-and-access",{"path":698,"title":699,"stem":700},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch24-optional-avoiding-null-pointer-exceptions\u002F24-optional-avoiding-null-pointer-exceptions","Optional: Avoiding Null Pointer Exceptions — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch24-optional-avoiding-null-pointer-exceptions\u002F24-optional-avoiding-null-pointer-exceptions",{"path":702,"title":703,"stem":704},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F1-what-is-command-based-programming","What Is Command-Based Programming? — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F25.1-what-is-command-based-programming",{"path":706,"title":707,"stem":708},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F2-commands-and-command-compositions","Commands & Command Compositions — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F25.2-commands-and-command-compositions",{"path":710,"title":711,"stem":712},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F3-the-command-scheduler","The Command Scheduler — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F25.3-the-command-scheduler",{"path":714,"title":715,"stem":716},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F4-state-machines-logic","State Machines: Logic — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F25.4-state-machines-logic",{"path":718,"title":719,"stem":720},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F5-managing-transitions","Managing Transitions — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F25.5-managing-transitions",{"path":722,"title":723,"stem":724},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F6-binding-commands-to-triggers","Binding Commands to Triggers — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F25.6-binding-commands-to-triggers",{"path":726,"title":727,"stem":728},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F7-structuring-a-command-based-robot-project","Structuring a Command-Based Robot Project — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch25-command-based-programming\u002F25.7-structuring-a-command-based-robot-project",{"path":730,"title":731,"stem":732},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch26-architecture-takeaways\u002F26-architecture-takeaways","Architecture Takeaways — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch26-architecture-takeaways\u002F26-architecture-takeaways",{"path":734,"title":735,"stem":736},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch27-program-design-and-abstraction\u002F1-abstraction-and-program-design","Abstraction and Program Design — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch27-program-design-and-abstraction\u002F27.1-abstraction-and-program-design",{"path":738,"title":739,"stem":740},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch28-algorithms-searching-sorting-recursion\u002F1-searching-algorithms","Searching Algorithms — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch28-algorithms-searching-sorting-recursion\u002F28.1-searching-algorithms",{"path":742,"title":743,"stem":744},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch28-algorithms-searching-sorting-recursion\u002F2-sorting-algorithms","Sorting Algorithms — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch28-algorithms-searching-sorting-recursion\u002F28.2-sorting-algorithms",{"path":746,"title":747,"stem":748},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch28-algorithms-searching-sorting-recursion\u002F3-recursion","Recursion — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch28-algorithms-searching-sorting-recursion\u002F28.3-recursion",{"path":750,"title":751,"stem":752},"\u002Fshockwave-curriculum\u002Fexamples\u002Fch28-algorithms-searching-sorting-recursion\u002F4-recursive-searching-and-sorting","Recursive Searching and Sorting — Worked Example","shockwave-curriculum\u002Fexamples\u002Fch28-algorithms-searching-sorting-recursion\u002F28.4-recursive-searching-and-sorting",[754,758,762,766,770,774,778,782,786,790,794,798,802,806,810,814,818,822,826,830,834,838,842,846,850,854,858,862,866,870,874,878,882,886,890,894,898,902,906,910,914,918,922,926,930,934,938,942,946,950,954,958,962,966,970,974,978,982,986,990,994,998,1002,1006,1010,1014,1018,1022,1026,1030,1034,1038,1042,1046,1050,1054,1058,1062,1066],{"path":755,"title":756,"stem":757},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch01-why-java-for-frc\u002F2-intro-to-algorithms-programming-and-compilers","Intro to Algorithms, Programming and Compilers — Exercises","shockwave-curriculum\u002Fexercises\u002Fch01-why-java-for-frc\u002F1.2-intro-to-algorithms-programming-and-compilers",{"path":759,"title":760,"stem":761},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch02-variables-and-types\u002F1-variables-and-data-types","Variables & Data Types — Exercises","shockwave-curriculum\u002Fexercises\u002Fch02-variables-and-types\u002F2.1-variables-and-data-types",{"path":763,"title":764,"stem":765},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch02-variables-and-types\u002F2-expressions-and-output","Expressions & Output — Exercises","shockwave-curriculum\u002Fexercises\u002Fch02-variables-and-types\u002F2.2-expressions-and-output",{"path":767,"title":768,"stem":769},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch02-variables-and-types\u002F3-assignment-and-input","Assignment & Input — Exercises","shockwave-curriculum\u002Fexercises\u002Fch02-variables-and-types\u002F2.3-assignment-and-input",{"path":771,"title":772,"stem":773},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch02-variables-and-types\u002F4-casting-and-ranges-of-values","Casting & Ranges of Values — Exercises","shockwave-curriculum\u002Fexercises\u002Fch02-variables-and-types\u002F2.4-casting-and-ranges-of-values",{"path":775,"title":776,"stem":777},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch02-variables-and-types\u002F5-compound-assignment-operators","Compound Assignment Operators — Exercises","shockwave-curriculum\u002Fexercises\u002Fch02-variables-and-types\u002F2.5-compound-assignment-operators",{"path":779,"title":780,"stem":781},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch03-apis-libraries-and-documentation\u002F1-apis-and-libraries","APIs and Libraries — Exercises","shockwave-curriculum\u002Fexercises\u002Fch03-apis-libraries-and-documentation\u002F3.1-apis-and-libraries",{"path":783,"title":784,"stem":785},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch03-apis-libraries-and-documentation\u002F2-documentation-with-comments-and-preconditions","Documentation with Comments and Preconditions — Exercises","shockwave-curriculum\u002Fexercises\u002Fch03-apis-libraries-and-documentation\u002F3.2-documentation-with-comments-and-preconditions",{"path":787,"title":788,"stem":789},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch03-apis-libraries-and-documentation\u002F3-packages-and-imports","Packages & Imports — Exercises","shockwave-curriculum\u002Fexercises\u002Fch03-apis-libraries-and-documentation\u002F3.3-packages-and-imports",{"path":791,"title":792,"stem":793},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F1-methods-signatures-and-parameters","Methods, Signatures & Parameters — Exercises","shockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F4.1-methods-signatures-and-parameters",{"path":795,"title":796,"stem":797},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F2-calling-class-methods","Calling Class Methods — Exercises","shockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F4.2-calling-class-methods",{"path":799,"title":800,"stem":801},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F3-using-the-math-class","Using the Math Class — Exercises","shockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F4.3-using-the-math-class",{"path":803,"title":804,"stem":805},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F4-objects-instances-of-classes","Objects — Instances of Classes — Exercises","shockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F4.4-objects-instances-of-classes",{"path":807,"title":808,"stem":809},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F5-creating-and-initializing-objects-constructors","Creating & Initializing Objects: Constructors — Exercises","shockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F4.5-creating-and-initializing-objects-constructors",{"path":811,"title":812,"stem":813},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F6-calling-instance-methods","Calling Instance Methods — Exercises","shockwave-curriculum\u002Fexercises\u002Fch04-using-objects-and-calling-methods\u002F4.6-calling-instance-methods",{"path":815,"title":816,"stem":817},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F1-5.2-if-statements-and-for-loops","if Statements & For Loops — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.1-5.2-if-statements-and-for-loops",{"path":819,"title":820,"stem":821},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F10-nested-iteration","Nested Iteration — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.10-nested-iteration",{"path":823,"title":824,"stem":825},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F11-informal-runtime-analysis-of-loops","Informal Runtime Analysis of Loops — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.11-informal-runtime-analysis-of-loops",{"path":827,"title":828,"stem":829},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F12-switch-statements-and-expressions","switch Statements and Expressions — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.12-switch-statements-and-expressions",{"path":831,"title":832,"stem":833},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F3-algorithms-with-selection-and-repetition","Algorithms with Selection and Repetition — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.3-algorithms-with-selection-and-repetition",{"path":835,"title":836,"stem":837},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F4-boolean-expressions","Boolean Expressions — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.4-boolean-expressions",{"path":839,"title":840,"stem":841},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5-nested-if-statements","Nested if Statements — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.5-nested-if-statements",{"path":843,"title":844,"stem":845},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F6-compound-boolean-expressions","Compound Boolean Expressions — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.6-compound-boolean-expressions",{"path":847,"title":848,"stem":849},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F7-comparing-boolean-expressions-de-morgans-laws","Comparing Boolean Expressions (De Morgan's Laws) — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.7-comparing-boolean-expressions-de-morgans-laws",{"path":851,"title":852,"stem":853},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F8-while-loops","While Loops — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.8-while-loops",{"path":855,"title":856,"stem":857},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F9-implementing-selection-and-iteration-algorithms","Implementing Selection and Iteration Algorithms — Exercises","shockwave-curriculum\u002Fexercises\u002Fch05-control-structures\u002F5.9-implementing-selection-and-iteration-algorithms",{"path":859,"title":860,"stem":861},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch06-strings\u002F1-strings","Strings — Exercises","shockwave-curriculum\u002Fexercises\u002Fch06-strings\u002F6.1-strings",{"path":863,"title":864,"stem":865},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch06-strings\u002F2-string-algorithms","String Algorithms — Exercises","shockwave-curriculum\u002Fexercises\u002Fch06-strings\u002F6.2-string-algorithms",{"path":867,"title":868,"stem":869},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch07-the-class-blueprint\u002F1-anatomy-of-a-java-class","Anatomy of a Java Class — Exercises","shockwave-curriculum\u002Fexercises\u002Fch07-the-class-blueprint\u002F7.1-anatomy-of-a-java-class",{"path":871,"title":872,"stem":873},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch07-the-class-blueprint\u002F2-methods-how-to-write-them","Methods: How to Write Them — Exercises","shockwave-curriculum\u002Fexercises\u002Fch07-the-class-blueprint\u002F7.2-methods-how-to-write-them",{"path":875,"title":876,"stem":877},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch07-the-class-blueprint\u002F3-methods-passing-and-returning-references-of-an-object","Methods: Passing & Returning References of an Object — Exercises","shockwave-curriculum\u002Fexercises\u002Fch07-the-class-blueprint\u002F7.3-methods-passing-and-returning-references-of-an-object",{"path":879,"title":880,"stem":881},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch07-the-class-blueprint\u002F4-class-static-variables-and-methods","Class (static) Variables & Methods — Exercises","shockwave-curriculum\u002Fexercises\u002Fch07-the-class-blueprint\u002F7.4-class-static-variables-and-methods",{"path":883,"title":884,"stem":885},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch08-constructors-and-this\u002F1-8.2-constructors-and-this","Constructors & \"this\" — Exercises","shockwave-curriculum\u002Fexercises\u002Fch08-constructors-and-this\u002F8.1-8.2-constructors-and-this",{"path":887,"title":888,"stem":889},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F1-array-creation-and-access","Array Creation and Access — Exercises","shockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F9.1-array-creation-and-access",{"path":891,"title":892,"stem":893},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F2-arraylist-and-its-methods","ArrayList and its Methods — Exercises","shockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F9.2-arraylist-and-its-methods",{"path":895,"title":896,"stem":897},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F3-optional-hashmap-dictionary-data-structure","HashMap (Dictionary) Data Structure — Exercises","shockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F9.3-optional-hashmap-dictionary-data-structure",{"path":899,"title":900,"stem":901},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F4-array-traversals","Array Traversals — Exercises","shockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F9.4-array-traversals",{"path":903,"title":904,"stem":905},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F5-implementing-array-algorithms","Implementing Array Algorithms — Exercises","shockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F9.5-implementing-array-algorithms",{"path":907,"title":908,"stem":909},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F6-arraylist-traversals","ArrayList Traversals — Exercises","shockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F9.6-arraylist-traversals",{"path":911,"title":912,"stem":913},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F7-implementing-arraylist-algorithms","Implementing ArrayList Algorithms — Exercises","shockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F9.7-implementing-arraylist-algorithms",{"path":915,"title":916,"stem":917},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F8-using-text-files","Using Text Files — Exercises","shockwave-curriculum\u002Fexercises\u002Fch09-storing-data\u002F9.8-using-text-files",{"path":919,"title":920,"stem":921},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch10-2d-arrays\u002F1-2d-array-creation-and-access","2D Array Creation and Access — Exercises","shockwave-curriculum\u002Fexercises\u002Fch10-2d-arrays\u002F10.1-2d-array-creation-and-access",{"path":923,"title":924,"stem":925},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch10-2d-arrays\u002F2-2d-array-traversals-nested-loops","2D Array Traversals: Nested Loops — Exercises","shockwave-curriculum\u002Fexercises\u002Fch10-2d-arrays\u002F10.2-2d-array-traversals-nested-loops",{"path":927,"title":928,"stem":929},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch10-2d-arrays\u002F3-implementing-2d-array-algorithms","Implementing 2D Array Algorithms — Exercises","shockwave-curriculum\u002Fexercises\u002Fch10-2d-arrays\u002F10.3-implementing-2d-array-algorithms",{"path":931,"title":932,"stem":933},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch11-enums-named-choices\u002F11-enums-named-choices","Enums: Named Choices — Exercises","shockwave-curriculum\u002Fexercises\u002Fch11-enums-named-choices\u002F11-enums-named-choices",{"path":935,"title":936,"stem":937},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch12-exceptions-and-try-catch\u002F12-exceptions-and-try-catch","Exceptions & try\u002Fcatch — Exercises","shockwave-curriculum\u002Fexercises\u002Fch12-exceptions-and-try-catch\u002F12-exceptions-and-try-catch",{"path":939,"title":940,"stem":941},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch13-common-gotchas\u002F13-common-gotchas","Common Gotchas — Exercises","shockwave-curriculum\u002Fexercises\u002Fch13-common-gotchas\u002F13-common-gotchas",{"path":943,"title":944,"stem":945},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch14-why-design-patterns\u002F14-why-design-patterns","Why Design Patterns? — Exercises","shockwave-curriculum\u002Fexercises\u002Fch14-why-design-patterns\u002F14-why-design-patterns",{"path":947,"title":948,"stem":949},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch15-advanced-collections\u002F15-advanced-collections","Advanced Collections (Set\u002FQueue\u002FMap) — Exercises","shockwave-curriculum\u002Fexercises\u002Fch15-advanced-collections\u002F15-advanced-collections",{"path":951,"title":952,"stem":953},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch16-writing-your-own-generics\u002F16-writing-your-own-generics","Writing Your Own Generics — Exercises","shockwave-curriculum\u002Fexercises\u002Fch16-writing-your-own-generics\u002F16-writing-your-own-generics",{"path":955,"title":956,"stem":957},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F1-inheritance-superclass-subclass","Inheritance, Superclass, Subclass — Exercises","shockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F17.1-inheritance-superclass-subclass",{"path":959,"title":960,"stem":961},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F2-inheritance-and-constructors","Inheritance and Constructors — Exercises","shockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F17.2-inheritance-and-constructors",{"path":963,"title":964,"stem":965},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F3-inheritance-hierarchies","Inheritance Hierarchies — Exercises","shockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F17.3-inheritance-hierarchies",{"path":967,"title":968,"stem":969},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F4-object-superclass","Object Superclass — Exercises","shockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F17.4-object-superclass",{"path":971,"title":972,"stem":973},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F5-abstract-classes-and-methods","Abstract Classes and Methods — Exercises","shockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F17.5-abstract-classes-and-methods",{"path":975,"title":976,"stem":977},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch18-polymorphism-many-forms\u002F1-overriding-methods","Overriding Methods — Exercises","shockwave-curriculum\u002Fexercises\u002Fch18-polymorphism-many-forms\u002F18.1-overriding-methods",{"path":979,"title":980,"stem":981},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch18-polymorphism-many-forms\u002F2-super-keyword","super Keyword — Exercises","shockwave-curriculum\u002Fexercises\u002Fch18-polymorphism-many-forms\u002F18.2-super-keyword",{"path":983,"title":984,"stem":985},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch18-polymorphism-many-forms\u002F3-polymorphism","Polymorphism — Exercises","shockwave-curriculum\u002Fexercises\u002Fch18-polymorphism-many-forms\u002F18.3-polymorphism",{"path":987,"title":988,"stem":989},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch19-interfaces-as-contracts\u002F19-interfaces-as-contracts","Interfaces as Contracts — Exercises","shockwave-curriculum\u002Fexercises\u002Fch19-interfaces-as-contracts\u002F19-interfaces-as-contracts",{"path":991,"title":992,"stem":993},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch19-interfaces-as-contracts\u002F1-lambdas-and-method-references","Lambdas & Method References — Exercises","shockwave-curriculum\u002Fexercises\u002Fch19-interfaces-as-contracts\u002F19.1-lambdas-and-method-references",{"path":995,"title":996,"stem":997},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch20-the-io-layer-pattern\u002F20-the-io-layer-pattern","The IO-Layer Pattern — Exercises","shockwave-curriculum\u002Fexercises\u002Fch20-the-io-layer-pattern\u002F20-the-io-layer-pattern",{"path":999,"title":1000,"stem":1001},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch21-static-factories\u002F21-static-factories","Static Factories — Exercises","shockwave-curriculum\u002Fexercises\u002Fch21-static-factories\u002F21-static-factories",{"path":1003,"title":1004,"stem":1005},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch22-the-builder-pattern\u002F22-the-builder-pattern","The Builder Pattern — Exercises","shockwave-curriculum\u002Fexercises\u002Fch22-the-builder-pattern\u002F22-the-builder-pattern",{"path":1007,"title":1008,"stem":1009},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch23-encapsulation-and-final\u002F1-scope-and-access","Access, final, and Immutability — Exercises","shockwave-curriculum\u002Fexercises\u002Fch23-encapsulation-and-final\u002F23.1-scope-and-access",{"path":1011,"title":1012,"stem":1013},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch24-optional-avoiding-null-pointer-exceptions\u002F24-optional-avoiding-null-pointer-exceptions","Optional: Avoiding Null Pointer Exceptions — Exercises","shockwave-curriculum\u002Fexercises\u002Fch24-optional-avoiding-null-pointer-exceptions\u002F24-optional-avoiding-null-pointer-exceptions",{"path":1015,"title":1016,"stem":1017},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F1-what-is-command-based-programming","What Is Command-Based Programming? — Exercises","shockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F25.1-what-is-command-based-programming",{"path":1019,"title":1020,"stem":1021},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F2-commands-and-command-compositions","Commands & Command Compositions — Exercises","shockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F25.2-commands-and-command-compositions",{"path":1023,"title":1024,"stem":1025},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F3-the-command-scheduler","The Command Scheduler — Exercises","shockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F25.3-the-command-scheduler",{"path":1027,"title":1028,"stem":1029},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F4-state-machines-logic","State Machines: Logic — Exercises","shockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F25.4-state-machines-logic",{"path":1031,"title":1032,"stem":1033},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F5-managing-transitions","Managing Transitions — Exercises","shockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F25.5-managing-transitions",{"path":1035,"title":1036,"stem":1037},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F6-binding-commands-to-triggers","Binding Commands to Triggers — Exercises","shockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F25.6-binding-commands-to-triggers",{"path":1039,"title":1040,"stem":1041},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F7-structuring-a-command-based-robot-project","Structuring a Command-Based Robot Project — Exercises","shockwave-curriculum\u002Fexercises\u002Fch25-command-based-programming\u002F25.7-structuring-a-command-based-robot-project",{"path":1043,"title":1044,"stem":1045},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch26-architecture-takeaways\u002F26-architecture-takeaways","Architecture Takeaways — Exercises","shockwave-curriculum\u002Fexercises\u002Fch26-architecture-takeaways\u002F26-architecture-takeaways",{"path":1047,"title":1048,"stem":1049},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch27-program-design-and-abstraction\u002F1-abstraction-and-program-design","Abstraction and Program Design — Exercises","shockwave-curriculum\u002Fexercises\u002Fch27-program-design-and-abstraction\u002F27.1-abstraction-and-program-design",{"path":1051,"title":1052,"stem":1053},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch27-program-design-and-abstraction\u002F2-impact-of-program-design","Impact of Program Design — Exercises","shockwave-curriculum\u002Fexercises\u002Fch27-program-design-and-abstraction\u002F27.2-impact-of-program-design",{"path":1055,"title":1056,"stem":1057},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch28-algorithms-searching-sorting-recursion\u002F1-searching-algorithms","Searching Algorithms — Exercises","shockwave-curriculum\u002Fexercises\u002Fch28-algorithms-searching-sorting-recursion\u002F28.1-searching-algorithms",{"path":1059,"title":1060,"stem":1061},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch28-algorithms-searching-sorting-recursion\u002F2-sorting-algorithms","Sorting Algorithms — Exercises","shockwave-curriculum\u002Fexercises\u002Fch28-algorithms-searching-sorting-recursion\u002F28.2-sorting-algorithms",{"path":1063,"title":1064,"stem":1065},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch28-algorithms-searching-sorting-recursion\u002F3-recursion","Recursion — Exercises","shockwave-curriculum\u002Fexercises\u002Fch28-algorithms-searching-sorting-recursion\u002F28.3-recursion",{"path":1067,"title":1068,"stem":1069},"\u002Fshockwave-curriculum\u002Fexercises\u002Fch28-algorithms-searching-sorting-recursion\u002F4-recursive-searching-and-sorting","Recursive Searching and Sorting — Exercises","shockwave-curriculum\u002Fexercises\u002Fch28-algorithms-searching-sorting-recursion\u002F28.4-recursive-searching-and-sorting",{"id":1071,"title":226,"body":1072,"description":1145,"extension":1591,"meta":1592,"navigation":1173,"path":225,"seo":1595,"stem":227,"__hash__":1596},"lessons\u002Fshockwave-curriculum\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F17.5-abstract-classes-and-methods.md",{"type":1073,"value":1074,"toc":1580},"minimark",[1075,1079,1084,1114,1118,1139,1210,1213,1228,1235,1239,1262,1266,1277,1314,1336,1340,1348,1413,1417,1440,1444,1462,1474,1478,1526,1530,1569,1576],[1076,1077,226],"h1",{"id":1078},"abstract-classes-and-methods",[1080,1081,1083],"h2",{"id":1082},"a-class-that-shouldnt-be-instantiated","A Class That Shouldn't Be Instantiated",[1085,1086,1087,1088,1092,1093,1096,1097,1099,1100,1103,1104,1106,1107,1109,1110,1113],"p",{},"Every example so far could build a plain ",[1089,1090,1091],"code",{},"RobotPart"," — Lesson 17.3 even wrote ",[1089,1094,1095],{},"new RobotPart(\"Generic\")",". But on a real robot there's no such thing as \"just a robot part\": every part is an intake, a shooter, a climber. And ",[1089,1098,1091],{},"'s ",[1089,1101,1102],{},"stop()"," only prints a message, while every real part has to stop its own hardware in its own way. What the design really wants to say is \"",[1089,1105,1091],{}," is only a starting point — every real part must be a subclass, and every subclass must write its own ",[1089,1108,1102],{},".\" Java says exactly that with the keyword ",[1089,1111,1112],{},"abstract",".",[1080,1115,1117],{"id":1116},"abstract-classes","Abstract Classes",[1085,1119,1120,1121,1123,1124,1128,1129,1132,1133,1135,1136,1138],{},"Writing ",[1089,1122,1112],{}," in the class declaration makes it an ",[1125,1126,1127],"strong",{},"abstract class",": a class that can be extended, but never instantiated with ",[1089,1130,1131],{},"new",". Here's ",[1089,1134,1091],{}," from Lesson 17.1 as an abstract class, with ",[1089,1137,1102],{}," turned into an abstract method:",[1140,1141,1146],"pre",{"className":1142,"code":1143,"language":1144,"meta":1145,"style":1145},"language-java shiki shiki-themes github-light github-dark","public abstract class RobotPart\n{\n    private String name;\n\n    public RobotPart(String name) { this.name = name; }\n    public String getName() { return name; }\n    public void log(String msg) { System.out.println(\"[\" + name + \"] \" + msg); }\n\n    public abstract void stop();  \u002F\u002F no body: every subclass writes its own\n}\n","java","",[1089,1147,1148,1156,1162,1168,1175,1181,1187,1193,1198,1204],{"__ignoreMap":1145},[1149,1150,1153],"span",{"class":1151,"line":1152},"line",1,[1149,1154,1155],{},"public abstract class RobotPart\n",[1149,1157,1159],{"class":1151,"line":1158},2,[1149,1160,1161],{},"{\n",[1149,1163,1165],{"class":1151,"line":1164},3,[1149,1166,1167],{},"    private String name;\n",[1149,1169,1171],{"class":1151,"line":1170},4,[1149,1172,1174],{"emptyLinePlaceholder":1173},true,"\n",[1149,1176,1178],{"class":1151,"line":1177},5,[1149,1179,1180],{},"    public RobotPart(String name) { this.name = name; }\n",[1149,1182,1184],{"class":1151,"line":1183},6,[1149,1185,1186],{},"    public String getName() { return name; }\n",[1149,1188,1190],{"class":1151,"line":1189},7,[1149,1191,1192],{},"    public void log(String msg) { System.out.println(\"[\" + name + \"] \" + msg); }\n",[1149,1194,1196],{"class":1151,"line":1195},8,[1149,1197,1174],{"emptyLinePlaceholder":1173},[1149,1199,1201],{"class":1151,"line":1200},9,[1149,1202,1203],{},"    public abstract void stop();  \u002F\u002F no body: every subclass writes its own\n",[1149,1205,1207],{"class":1151,"line":1206},10,[1149,1208,1209],{},"}\n",[1085,1211,1212],{},"Trying to build one directly is now a compile error:",[1140,1214,1216],{"className":1142,"code":1215,"language":1144,"meta":1145,"style":1145},"\u002F\u002F ERROR: RobotPart is abstract; cannot be instantiated\nRobotPart generic = new RobotPart(\"Generic\");\n",[1089,1217,1218,1223],{"__ignoreMap":1145},[1149,1219,1220],{"class":1151,"line":1152},[1149,1221,1222],{},"\u002F\u002F ERROR: RobotPart is abstract; cannot be instantiated\n",[1149,1224,1225],{"class":1151,"line":1158},[1149,1226,1227],{},"RobotPart generic = new RobotPart(\"Generic\");\n",[1085,1229,1230,1231,1234],{},"A class that can be instantiated — every class you've written until now — is called a ",[1125,1232,1233],{},"concrete"," class.",[1080,1236,1238],{"id":1237},"abstract-methods","Abstract Methods",[1085,1240,1241,1242,1245,1246,1248,1249,1252,1253,1255,1256,1258,1259,1261],{},"An ",[1125,1243,1244],{},"abstract method"," is declared with ",[1089,1247,1112],{},", has a signature, and ends in a semicolon instead of a body: ",[1089,1250,1251],{},"public abstract void stop();"," says \"every ",[1089,1254,1091],{}," has a ",[1089,1257,1102],{}," method\" without saying what it does. A class that declares an abstract method must itself be marked ",[1089,1260,1112],{}," — otherwise it doesn't compile.",[1080,1263,1265],{"id":1264},"concrete-subclasses-must-fill-in-every-abstract-method","Concrete Subclasses Must Fill In Every Abstract Method",[1085,1267,1268,1269,1272,1273,1276],{},"A concrete subclass must provide a body for every abstract method it inherits. Writing that body is called ",[1125,1270,1271],{},"implementing"," the method — it uses the same syntax as overriding (Lesson 18.1), including ",[1089,1274,1275],{},"@Override"," (Lesson 17.4):",[1140,1278,1280],{"className":1142,"code":1279,"language":1144,"meta":1145,"style":1145},"public class Intake extends RobotPart\n{\n    public Intake(String name) { super(name); }\n\n    @Override\n    public void stop() { log(\"rollers off\"); }\n}\n",[1089,1281,1282,1287,1291,1296,1300,1305,1310],{"__ignoreMap":1145},[1149,1283,1284],{"class":1151,"line":1152},[1149,1285,1286],{},"public class Intake extends RobotPart\n",[1149,1288,1289],{"class":1151,"line":1158},[1149,1290,1161],{},[1149,1292,1293],{"class":1151,"line":1164},[1149,1294,1295],{},"    public Intake(String name) { super(name); }\n",[1149,1297,1298],{"class":1151,"line":1170},[1149,1299,1174],{"emptyLinePlaceholder":1173},[1149,1301,1302],{"class":1151,"line":1177},[1149,1303,1304],{},"    @Override\n",[1149,1306,1307],{"class":1151,"line":1183},[1149,1308,1309],{},"    public void stop() { log(\"rollers off\"); }\n",[1149,1311,1312],{"class":1151,"line":1189},[1149,1313,1209],{},[1085,1315,1316,1317,1320,1321,1323,1324,1327,1328,1330,1331,1335],{},"If ",[1089,1318,1319],{},"Intake"," left ",[1089,1322,1102],{}," out, the compiler would reject it: ",[1089,1325,1326],{},"Intake is not abstract and does not override abstract method stop() in RobotPart",". The only other option is for the subclass to be declared ",[1089,1329,1112],{}," too, passing the job down to ",[1332,1333,1334],"em",{},"its"," subclasses.",[1080,1337,1339],{"id":1338},"what-an-abstract-class-can-still-have","What an Abstract Class Can Still Have",[1085,1341,1342,1344,1345,1347],{},[1089,1343,1112],{}," removes only the ability to call ",[1089,1346,1131],{}," on the class itself. Everything else still works:",[1349,1350,1351,1364,1383,1396],"ul",{},[1352,1353,1354,1357,1358,1360,1361,1113],"li",{},[1125,1355,1356],{},"Fields"," — ",[1089,1359,1091],{}," still has its private ",[1089,1362,1363],{},"name",[1352,1365,1366,1357,1369,1372,1373,1375,1376,1379,1380,1113],{},[1125,1367,1368],{},"Constructors",[1089,1370,1371],{},"RobotPart(String name)"," still exists and still runs for every ",[1089,1374,1319],{},", through ",[1089,1377,1378],{},"super(name)"," (Lesson 17.2). You just can't call it with ",[1089,1381,1382],{},"new RobotPart(...)",[1352,1384,1385,1357,1388,1391,1392,1395],{},[1125,1386,1387],{},"Concrete methods",[1089,1389,1390],{},"getName()"," and ",[1089,1393,1394],{},"log()"," have bodies, and every subclass inherits them unchanged.",[1352,1397,1398,1357,1401,1403,1404,1391,1407,1410,1411,1113],{},[1125,1399,1400],{},"Use as a type",[1089,1402,1091],{}," is still a perfectly good variable, parameter, array, or collection type (Lesson 17.3): ",[1089,1405,1406],{},"RobotPart part = new Intake(\"Front\");",[1089,1408,1409],{},"RobotPart[] parts = { new Intake(\"Front\"), new Climber(\"Left\") };"," both compile. Every object they hold is some concrete subclass, so every one of them really has a ",[1089,1412,1102],{},[1080,1414,1416],{"id":1415},"abstract-classes-in-wpilib","Abstract Classes in WPILib",[1085,1418,1419,1420,1423,1424,1427,1428,1431,1432,1435,1436,1439],{},"WPILib uses the same tool. ",[1089,1421,1422],{},"MotorSafety"," (in ",[1089,1425,1426],{},"org.wpilib.hardware.motor",") is an abstract class that declares ",[1089,1429,1430],{},"public abstract void stopMotor();",", and ",[1089,1433,1434],{},"PWMMotorController",", the shared parent of WPILib's PWM motor controller classes, is abstract too. Robot code never writes ",[1089,1437,1438],{},"new PWMMotorController(...)"," — it constructs one of the specific controller classes that extend it, each of which inherits the shared code.",[1080,1441,1443],{"id":1442},"looking-ahead-interfaces","Looking Ahead: Interfaces",[1085,1445,1446,1447,1450,1451,1454,1455,1099,1457,1391,1459,1461],{},"Ch.19 introduces ",[1125,1448,1449],{},"interfaces",", a related tool: a type that lists methods a class promises to have, but that has no fields holding object state and no constructors, and that a class can ",[1089,1452,1453],{},"implements"," several of at once. Ch.19 compares the two directly. The short version: reach for an abstract class when the related classes share real state and code (like ",[1089,1456,1091],{},[1089,1458,1363],{},[1089,1460,1394],{},"), and an interface when they only share a set of methods.",[1085,1463,1464,1465,1467,1468,1470,1471,1473],{},"The rest of this course's ",[1089,1466,1091],{}," examples, starting in Ch.18, go back to the concrete ",[1089,1469,1091],{}," from Lesson 17.1, whose ",[1089,1472,1102],{}," has a body — Ch.18's lessons override and extend that body.",[1080,1475,1477],{"id":1476},"common-pitfalls","Common Pitfalls",[1349,1479,1480,1495,1508,1516],{},[1352,1481,1482,1485,1486,1488,1489,1491,1492,1494],{},[1125,1483,1484],{},"Trying to instantiate an abstract class."," ",[1089,1487,1095],{}," doesn't compile once ",[1089,1490,1091],{}," is abstract — build a concrete subclass instead, and store it in a ",[1089,1493,1091],{}," variable if you like.",[1352,1496,1497,1485,1500,1503,1504,1507],{},[1125,1498,1499],{},"Giving an abstract method a body, or leaving the semicolon off.",[1089,1501,1502],{},"public abstract void stop() { }"," doesn't compile — an abstract method is a signature followed by ",[1089,1505,1506],{},";",", with no braces at all.",[1352,1509,1510,1513,1514,1113],{},[1125,1511,1512],{},"Forgetting to implement an abstract method in a concrete subclass."," Every abstract method the subclass inherits needs a body, or the subclass must itself be declared ",[1089,1515,1112],{},[1352,1517,1518,1521,1522,1525],{},[1125,1519,1520],{},"Thinking an abstract class can't have constructors or fields."," It can have both; its constructor runs through ",[1089,1523,1524],{},"super(...)"," from each subclass.",[1080,1527,1529],{"id":1528},"key-takeaways","Key Takeaways",[1349,1531,1532,1540,1545,1554,1560],{},[1352,1533,1241,1534,1536,1537,1539],{},[1089,1535,1112],{}," class can be extended but never instantiated with ",[1089,1538,1131],{},"; a class that can be instantiated is concrete.",[1352,1541,1542,1543,1113],{},"An abstract method has a signature and a semicolon but no body; a class that declares one must itself be ",[1089,1544,1112],{},[1352,1546,1547,1548,1550,1551,1553],{},"A concrete subclass must implement every inherited abstract method (same syntax as overriding, with ",[1089,1549,1275],{},"), or be declared ",[1089,1552,1112],{}," itself.",[1352,1555,1556,1557,1559],{},"Abstract classes still have fields, constructors (run through ",[1089,1558,1524],{},"), concrete methods, and can be used as variable, parameter, and collection types.",[1352,1561,1562,1563,1565,1566,1568],{},"WPILib uses abstract classes too (",[1089,1564,1422],{},", ",[1089,1567,1434],{},"); Ch.19's interfaces are the related tool for sharing methods without shared state.",[1085,1570,1571,1572,1575],{},"Authored for this course (new lesson from the 2026-09 content audit; no ",[1089,1573,1574],{},"csawesome-2026"," source).",[1577,1578,1579],"style",{},"html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .dark .shiki span {color: var(--shiki-dark);background: var(--shiki-dark-bg);font-style: var(--shiki-dark-font-style);font-weight: var(--shiki-dark-font-weight);text-decoration: var(--shiki-dark-text-decoration);}html.dark .shiki span {color: var(--shiki-dark);background: var(--shiki-dark-bg);font-style: var(--shiki-dark-font-style);font-weight: var(--shiki-dark-font-weight);text-decoration: var(--shiki-dark-text-decoration);}",{"title":1145,"searchDepth":1158,"depth":1158,"links":1581},[1582,1583,1584,1585,1586,1587,1588,1589,1590],{"id":1082,"depth":1158,"text":1083},{"id":1116,"depth":1158,"text":1117},{"id":1237,"depth":1158,"text":1238},{"id":1264,"depth":1158,"text":1265},{"id":1338,"depth":1158,"text":1339},{"id":1415,"depth":1158,"text":1416},{"id":1442,"depth":1158,"text":1443},{"id":1476,"depth":1158,"text":1477},{"id":1528,"depth":1158,"text":1529},"md",{"outlineRef":1593,"status":1594},"17.5 — Abstract Classes and Methods","new — authored lesson (added in the 2026-09 content audit; no CSA counterpart)",{"title":226,"description":1145},"1w7tj257onowvGnT3MdUgL0WybE4fra0OMNWiwIGRZA",{"id":1598,"title":659,"body":1599,"description":1145,"extension":1591,"meta":2341,"navigation":1173,"path":658,"seo":2344,"stem":660,"__hash__":2345},"examples\u002Fshockwave-curriculum\u002Fexamples\u002Fch17-inheritance-and-abstractions\u002F17.5-abstract-classes-and-methods.md",{"type":1073,"value":1600,"toc":2331},[1601,1604,1608,1615,1619,1650,1662,1666,1749,1757,1761,1773,1906,1915,1919,2195,2217,2221,2229,2240,2244,2255,2264,2270,2285,2291,2297,2301,2329],[1076,1602,659],{"id":1603},"abstract-classes-and-methods-worked-example",[1080,1605,1607],{"id":1606},"problem","Problem",[1085,1609,1610,1611,1614],{},"The robot's LED strip can play several light patterns, like a blinking pattern and a rainbow pattern. Every pattern has a name, and every pattern can be played — but each one plays in its own way, and there's no sensible \"plain pattern\" that isn't one of the specific kinds. Write a ",[1089,1612,1613],{},"LightPattern"," superclass that holds the shared name, can't be built on its own, and forces every kind of pattern to say how it plays.",[1080,1616,1618],{"id":1617},"step-1-decide-whats-shared-and-what-isnt","Step 1: Decide What's Shared and What Isn't",[1349,1620,1621,1633,1641],{},[1352,1622,1623,1626,1627,1629,1630,1632],{},[1125,1624,1625],{},"Shared by every pattern, with the same code:"," a ",[1089,1628,1363],{}," field, a constructor that sets it, and a ",[1089,1631,1390],{}," getter.",[1352,1634,1635,1485,1638,1113],{},[1125,1636,1637],{},"Every pattern has it, but each one's code is different:",[1089,1639,1640],{},"play()",[1352,1642,1643,1646,1647,1649],{},[1125,1644,1645],{},"Should never exist on its own:"," a plain ",[1089,1648,1613],{}," object.",[1085,1651,1652,1653,1655,1656,1658,1659,1661],{},"The last two points are exactly what ",[1089,1654,1112],{}," is for: ",[1089,1657,1640],{}," becomes an abstract method, which makes ",[1089,1660,1613],{}," an abstract class.",[1080,1663,1665],{"id":1664},"step-2-write-the-abstract-superclass","Step 2: Write the Abstract Superclass",[1140,1667,1669],{"className":1142,"code":1668,"language":1144,"meta":1145,"style":1145},"abstract class LightPattern\n{\n    private String name;\n\n    public LightPattern(String name)\n    {\n        this.name = name;\n    }\n\n    public String getName()\n    {\n        return name;\n    }\n\n    public abstract void play();\n}\n",[1089,1670,1671,1676,1680,1684,1688,1693,1698,1703,1708,1712,1717,1722,1728,1733,1738,1744],{"__ignoreMap":1145},[1149,1672,1673],{"class":1151,"line":1152},[1149,1674,1675],{},"abstract class LightPattern\n",[1149,1677,1678],{"class":1151,"line":1158},[1149,1679,1161],{},[1149,1681,1682],{"class":1151,"line":1164},[1149,1683,1167],{},[1149,1685,1686],{"class":1151,"line":1170},[1149,1687,1174],{"emptyLinePlaceholder":1173},[1149,1689,1690],{"class":1151,"line":1177},[1149,1691,1692],{},"    public LightPattern(String name)\n",[1149,1694,1695],{"class":1151,"line":1183},[1149,1696,1697],{},"    {\n",[1149,1699,1700],{"class":1151,"line":1189},[1149,1701,1702],{},"        this.name = name;\n",[1149,1704,1705],{"class":1151,"line":1195},[1149,1706,1707],{},"    }\n",[1149,1709,1710],{"class":1151,"line":1200},[1149,1711,1174],{"emptyLinePlaceholder":1173},[1149,1713,1714],{"class":1151,"line":1206},[1149,1715,1716],{},"    public String getName()\n",[1149,1718,1720],{"class":1151,"line":1719},11,[1149,1721,1697],{},[1149,1723,1725],{"class":1151,"line":1724},12,[1149,1726,1727],{},"        return name;\n",[1149,1729,1731],{"class":1151,"line":1730},13,[1149,1732,1707],{},[1149,1734,1736],{"class":1151,"line":1735},14,[1149,1737,1174],{"emptyLinePlaceholder":1173},[1149,1739,1741],{"class":1151,"line":1740},15,[1149,1742,1743],{},"    public abstract void play();\n",[1149,1745,1747],{"class":1151,"line":1746},16,[1149,1748,1209],{},[1085,1750,1751,1753,1754,1756],{},[1089,1752,1112],{}," goes in the class declaration and on the method. ",[1089,1755,1640],{}," has no body — just its signature and a semicolon. Everything else is an ordinary class: a private field, a constructor, and a concrete getter.",[1080,1758,1760],{"id":1759},"step-3-write-the-concrete-subclasses","Step 3: Write the Concrete Subclasses",[1085,1762,1763,1764,1766,1767,1769,1770,1772],{},"Each subclass passes its name up with ",[1089,1765,1524],{}," (Lesson 17.2) and implements ",[1089,1768,1640],{}," with its own body, marked ",[1089,1771,1275],{},":",[1140,1774,1776],{"className":1142,"code":1775,"language":1144,"meta":1145,"style":1145},"class BlinkPattern extends LightPattern\n{\n    public BlinkPattern()\n    {\n        super(\"Blink\");\n    }\n\n    @Override\n    public void play()\n    {\n        System.out.println(\"Blinking orange twice per second\");\n    }\n}\n\nclass RainbowPattern extends LightPattern\n{\n    public RainbowPattern()\n    {\n        super(\"Rainbow\");\n    }\n\n    @Override\n    public void play()\n    {\n        System.out.println(\"Cycling through the rainbow\");\n    }\n}\n",[1089,1777,1778,1783,1787,1792,1796,1801,1805,1809,1813,1818,1822,1827,1831,1835,1839,1844,1848,1854,1859,1865,1870,1875,1880,1885,1890,1896,1901],{"__ignoreMap":1145},[1149,1779,1780],{"class":1151,"line":1152},[1149,1781,1782],{},"class BlinkPattern extends LightPattern\n",[1149,1784,1785],{"class":1151,"line":1158},[1149,1786,1161],{},[1149,1788,1789],{"class":1151,"line":1164},[1149,1790,1791],{},"    public BlinkPattern()\n",[1149,1793,1794],{"class":1151,"line":1170},[1149,1795,1697],{},[1149,1797,1798],{"class":1151,"line":1177},[1149,1799,1800],{},"        super(\"Blink\");\n",[1149,1802,1803],{"class":1151,"line":1183},[1149,1804,1707],{},[1149,1806,1807],{"class":1151,"line":1189},[1149,1808,1174],{"emptyLinePlaceholder":1173},[1149,1810,1811],{"class":1151,"line":1195},[1149,1812,1304],{},[1149,1814,1815],{"class":1151,"line":1200},[1149,1816,1817],{},"    public void play()\n",[1149,1819,1820],{"class":1151,"line":1206},[1149,1821,1697],{},[1149,1823,1824],{"class":1151,"line":1719},[1149,1825,1826],{},"        System.out.println(\"Blinking orange twice per second\");\n",[1149,1828,1829],{"class":1151,"line":1724},[1149,1830,1707],{},[1149,1832,1833],{"class":1151,"line":1730},[1149,1834,1209],{},[1149,1836,1837],{"class":1151,"line":1735},[1149,1838,1174],{"emptyLinePlaceholder":1173},[1149,1840,1841],{"class":1151,"line":1740},[1149,1842,1843],{},"class RainbowPattern extends LightPattern\n",[1149,1845,1846],{"class":1151,"line":1746},[1149,1847,1161],{},[1149,1849,1851],{"class":1151,"line":1850},17,[1149,1852,1853],{},"    public RainbowPattern()\n",[1149,1855,1857],{"class":1151,"line":1856},18,[1149,1858,1697],{},[1149,1860,1862],{"class":1151,"line":1861},19,[1149,1863,1864],{},"        super(\"Rainbow\");\n",[1149,1866,1868],{"class":1151,"line":1867},20,[1149,1869,1707],{},[1149,1871,1873],{"class":1151,"line":1872},21,[1149,1874,1174],{"emptyLinePlaceholder":1173},[1149,1876,1878],{"class":1151,"line":1877},22,[1149,1879,1304],{},[1149,1881,1883],{"class":1151,"line":1882},23,[1149,1884,1817],{},[1149,1886,1888],{"class":1151,"line":1887},24,[1149,1889,1697],{},[1149,1891,1893],{"class":1151,"line":1892},25,[1149,1894,1895],{},"        System.out.println(\"Cycling through the rainbow\");\n",[1149,1897,1899],{"class":1151,"line":1898},26,[1149,1900,1707],{},[1149,1902,1904],{"class":1151,"line":1903},27,[1149,1905,1209],{},[1085,1907,1908,1909,1911,1912,1914],{},"Neither subclass is ",[1089,1910,1112],{},", so each one must implement ",[1089,1913,1640],{}," — and each does.",[1080,1916,1918],{"id":1917},"step-4-put-it-together","Step 4: Put It Together",[1140,1920,1922],{"className":1142,"code":1921,"language":1144,"meta":1145,"style":1145},"public class LightShow\n{\n    public static void main(String[] args)\n    {\n        LightPattern[] patterns = { new BlinkPattern(), new RainbowPattern() };\n\n        for (LightPattern p : patterns)\n        {\n            System.out.print(p.getName() + \": \");\n            p.play();\n        }\n    }\n}\n\nabstract class LightPattern\n{\n    private String name;\n\n    public LightPattern(String name)\n    {\n        this.name = name;\n    }\n\n    public String getName()\n    {\n        return name;\n    }\n\n    public abstract void play();\n}\n\nclass BlinkPattern extends LightPattern\n{\n    public BlinkPattern()\n    {\n        super(\"Blink\");\n    }\n\n    @Override\n    public void play()\n    {\n        System.out.println(\"Blinking orange twice per second\");\n    }\n}\n\nclass RainbowPattern extends LightPattern\n{\n    public RainbowPattern()\n    {\n        super(\"Rainbow\");\n    }\n\n    @Override\n    public void play()\n    {\n        System.out.println(\"Cycling through the rainbow\");\n    }\n}\n",[1089,1923,1924,1929,1933,1938,1942,1947,1951,1956,1961,1966,1971,1976,1980,1984,1988,1992,1996,2000,2004,2008,2012,2016,2020,2024,2028,2032,2036,2040,2045,2050,2055,2060,2065,2070,2075,2080,2085,2090,2095,2100,2105,2110,2115,2120,2125,2130,2135,2140,2145,2150,2155,2160,2165,2170,2175,2180,2185,2190],{"__ignoreMap":1145},[1149,1925,1926],{"class":1151,"line":1152},[1149,1927,1928],{},"public class LightShow\n",[1149,1930,1931],{"class":1151,"line":1158},[1149,1932,1161],{},[1149,1934,1935],{"class":1151,"line":1164},[1149,1936,1937],{},"    public static void main(String[] args)\n",[1149,1939,1940],{"class":1151,"line":1170},[1149,1941,1697],{},[1149,1943,1944],{"class":1151,"line":1177},[1149,1945,1946],{},"        LightPattern[] patterns = { new BlinkPattern(), new RainbowPattern() };\n",[1149,1948,1949],{"class":1151,"line":1183},[1149,1950,1174],{"emptyLinePlaceholder":1173},[1149,1952,1953],{"class":1151,"line":1189},[1149,1954,1955],{},"        for (LightPattern p : patterns)\n",[1149,1957,1958],{"class":1151,"line":1195},[1149,1959,1960],{},"        {\n",[1149,1962,1963],{"class":1151,"line":1200},[1149,1964,1965],{},"            System.out.print(p.getName() + \": \");\n",[1149,1967,1968],{"class":1151,"line":1206},[1149,1969,1970],{},"            p.play();\n",[1149,1972,1973],{"class":1151,"line":1719},[1149,1974,1975],{},"        }\n",[1149,1977,1978],{"class":1151,"line":1724},[1149,1979,1707],{},[1149,1981,1982],{"class":1151,"line":1730},[1149,1983,1209],{},[1149,1985,1986],{"class":1151,"line":1735},[1149,1987,1174],{"emptyLinePlaceholder":1173},[1149,1989,1990],{"class":1151,"line":1740},[1149,1991,1675],{},[1149,1993,1994],{"class":1151,"line":1746},[1149,1995,1161],{},[1149,1997,1998],{"class":1151,"line":1850},[1149,1999,1167],{},[1149,2001,2002],{"class":1151,"line":1856},[1149,2003,1174],{"emptyLinePlaceholder":1173},[1149,2005,2006],{"class":1151,"line":1861},[1149,2007,1692],{},[1149,2009,2010],{"class":1151,"line":1867},[1149,2011,1697],{},[1149,2013,2014],{"class":1151,"line":1872},[1149,2015,1702],{},[1149,2017,2018],{"class":1151,"line":1877},[1149,2019,1707],{},[1149,2021,2022],{"class":1151,"line":1882},[1149,2023,1174],{"emptyLinePlaceholder":1173},[1149,2025,2026],{"class":1151,"line":1887},[1149,2027,1716],{},[1149,2029,2030],{"class":1151,"line":1892},[1149,2031,1697],{},[1149,2033,2034],{"class":1151,"line":1898},[1149,2035,1727],{},[1149,2037,2038],{"class":1151,"line":1903},[1149,2039,1707],{},[1149,2041,2043],{"class":1151,"line":2042},28,[1149,2044,1174],{"emptyLinePlaceholder":1173},[1149,2046,2048],{"class":1151,"line":2047},29,[1149,2049,1743],{},[1149,2051,2053],{"class":1151,"line":2052},30,[1149,2054,1209],{},[1149,2056,2058],{"class":1151,"line":2057},31,[1149,2059,1174],{"emptyLinePlaceholder":1173},[1149,2061,2063],{"class":1151,"line":2062},32,[1149,2064,1782],{},[1149,2066,2068],{"class":1151,"line":2067},33,[1149,2069,1161],{},[1149,2071,2073],{"class":1151,"line":2072},34,[1149,2074,1791],{},[1149,2076,2078],{"class":1151,"line":2077},35,[1149,2079,1697],{},[1149,2081,2083],{"class":1151,"line":2082},36,[1149,2084,1800],{},[1149,2086,2088],{"class":1151,"line":2087},37,[1149,2089,1707],{},[1149,2091,2093],{"class":1151,"line":2092},38,[1149,2094,1174],{"emptyLinePlaceholder":1173},[1149,2096,2098],{"class":1151,"line":2097},39,[1149,2099,1304],{},[1149,2101,2103],{"class":1151,"line":2102},40,[1149,2104,1817],{},[1149,2106,2108],{"class":1151,"line":2107},41,[1149,2109,1697],{},[1149,2111,2113],{"class":1151,"line":2112},42,[1149,2114,1826],{},[1149,2116,2118],{"class":1151,"line":2117},43,[1149,2119,1707],{},[1149,2121,2123],{"class":1151,"line":2122},44,[1149,2124,1209],{},[1149,2126,2128],{"class":1151,"line":2127},45,[1149,2129,1174],{"emptyLinePlaceholder":1173},[1149,2131,2133],{"class":1151,"line":2132},46,[1149,2134,1843],{},[1149,2136,2138],{"class":1151,"line":2137},47,[1149,2139,1161],{},[1149,2141,2143],{"class":1151,"line":2142},48,[1149,2144,1853],{},[1149,2146,2148],{"class":1151,"line":2147},49,[1149,2149,1697],{},[1149,2151,2153],{"class":1151,"line":2152},50,[1149,2154,1864],{},[1149,2156,2158],{"class":1151,"line":2157},51,[1149,2159,1707],{},[1149,2161,2163],{"class":1151,"line":2162},52,[1149,2164,1174],{"emptyLinePlaceholder":1173},[1149,2166,2168],{"class":1151,"line":2167},53,[1149,2169,1304],{},[1149,2171,2173],{"class":1151,"line":2172},54,[1149,2174,1817],{},[1149,2176,2178],{"class":1151,"line":2177},55,[1149,2179,1697],{},[1149,2181,2183],{"class":1151,"line":2182},56,[1149,2184,1895],{},[1149,2186,2188],{"class":1151,"line":2187},57,[1149,2189,1707],{},[1149,2191,2193],{"class":1151,"line":2192},58,[1149,2194,1209],{},[1085,2196,2197,2198,2201,2202,2205,2206,2208,2209,2212,2213,2216],{},"As in 17.1, the class holding ",[1089,2199,2200],{},"main"," comes first, and it's the only ",[1089,2203,2204],{},"public"," class in the file. ",[1089,2207,1613],{}," is abstract, but it still works as the array's type (Lesson 17.3): every element is a concrete subclass object. ",[1089,2210,2211],{},"System.out.print"," (no ",[1089,2214,2215],{},"ln",") keeps the name and the pattern's line together.",[1080,2218,2220],{"id":2219},"what-it-prints","What It Prints",[1140,2222,2227],{"className":2223,"code":2225,"language":2226},[2224],"language-text","Blink: Blinking orange twice per second\nRainbow: Cycling through the rainbow\n","text",[1089,2228,2225],{"__ignoreMap":1145},[1085,2230,2231,2233,2234,2236,2237,2239],{},[1089,2232,1390],{}," comes from ",[1089,2235,1613],{}," for both objects; ",[1089,2238,1640],{}," runs each object's own version.",[1080,2241,2243],{"id":2242},"what-going-wrong-would-look-like","What Going Wrong Would Look Like",[1085,2245,2246,2251,2252,2254],{},[1125,2247,2248,2249,1113],{},"Building a plain ",[1089,2250,1613],{}," Adding this line to ",[1089,2253,2200],{}," doesn't compile:",[1140,2256,2258],{"className":1142,"code":2257,"language":1144,"meta":1145,"style":1145},"LightPattern plain = new LightPattern(\"Off\");\n",[1089,2259,2260],{"__ignoreMap":1145},[1149,2261,2262],{"class":1151,"line":1152},[1149,2263,2257],{},[1140,2265,2268],{"className":2266,"code":2267,"language":2226},[2224],"error: LightPattern is abstract; cannot be instantiated\n",[1089,2269,2267],{"__ignoreMap":1145},[1085,2271,2272,2277,2278,2281,2282,2284],{},[1125,2273,2274,2275,1113],{},"Forgetting to implement ",[1089,2276,1640],{}," If ",[1089,2279,2280],{},"RainbowPattern"," left out its ",[1089,2283,1640],{}," method, the compiler would reject the class:",[1140,2286,2289],{"className":2287,"code":2288,"language":2226},[2224],"error: RainbowPattern is not abstract and does not override abstract method play() in LightPattern\n",[1089,2290,2288],{"__ignoreMap":1145},[1085,2292,2293,2294,2296],{},"Both mistakes are caught before the program ever runs — that's the point of making ",[1089,2295,1613],{}," abstract.",[1080,2298,2300],{"id":2299},"recap","Recap",[1349,2302,2303,2306,2314,2322],{},[1352,2304,2305],{},"Put the code every subclass shares (field, constructor, getter) in the abstract class; declare the behavior that differs as an abstract method with no body.",[1352,2307,2308,2309,2311,2312,1113],{},"A class with an abstract method must itself be declared ",[1089,2310,1112],{},", and can't be instantiated with ",[1089,2313,1131],{},[1352,2315,2316,2317,2319,2320,1113],{},"Each concrete subclass calls ",[1089,2318,1524],{}," for the shared constructor and implements every abstract method with ",[1089,2321,1275],{},[1352,2323,2324,2325,2328],{},"The abstract class still works as a variable or array type: ",[1089,2326,2327],{},"LightPattern[] patterns"," holds any concrete subclass.",[1577,2330,1579],{},{"title":1145,"searchDepth":1158,"depth":1158,"links":2332},[2333,2334,2335,2336,2337,2338,2339,2340],{"id":1606,"depth":1158,"text":1607},{"id":1617,"depth":1158,"text":1618},{"id":1664,"depth":1158,"text":1665},{"id":1759,"depth":1158,"text":1760},{"id":1917,"depth":1158,"text":1918},{"id":2219,"depth":1158,"text":2220},{"id":2242,"depth":1158,"text":2243},{"id":2299,"depth":1158,"text":2300},{"outlineRef":1593,"pairsWith":2342,"status":2343},"[`lessons\u002Fch17-inheritance-and-abstractions\u002F17.5-abstract-classes-and-methods.md`](..\u002F..\u002Flessons\u002Fch17-inheritance-and-abstractions\u002F17.5-abstract-classes-and-methods.md)","new — authored worked example (fully solved, walked step by step — not a problem to attempt)",{"title":659,"description":1145},"VW7BHnkr2mgTuDGSErjc7MubLTqFuJmtYieZH4RnnSA",{"id":2347,"title":972,"body":2348,"description":1145,"extension":1591,"meta":3644,"navigation":1173,"path":971,"seo":3646,"stem":973,"__hash__":3647},"exercises\u002Fshockwave-curriculum\u002Fexercises\u002Fch17-inheritance-and-abstractions\u002F17.5-abstract-classes-and-methods.md",{"type":1073,"value":2349,"toc":3639},[2350,2353,2357,2363,2435,2438,2443,2489,2495,2519,2549,2553,2593,2686,2689,2739,2744,2861,2924,2928,2934,2945,2997,3009,3015,3020,3233,3238,3243,3249,3254,3259,3264,3268,3274,3278,3284,3289,3293,3299,3303,3309,3314,3318,3324,3328,3334,3339,3343,3349,3353,3359,3364,3603,3637],[1076,2351,972],{"id":2352},"abstract-classes-and-methods-exercises",[1080,2354,2356],{"id":2355},"multiple-choice","Multiple Choice",[1085,2358,2359,2362],{},[1125,2360,2361],{},"Question:"," Given this class:",[1140,2364,2366],{"className":1142,"code":2365,"language":1144,"meta":1145,"style":1145},"abstract class Gripper\n{\n    private String name;\n\n    public Gripper(String name)\n    {\n        this.name = name;\n    }\n\n    public String getName()\n    {\n        return name;\n    }\n\n    public abstract void grab();\n}\n",[1089,2367,2368,2373,2377,2381,2385,2390,2394,2398,2402,2406,2410,2414,2418,2422,2426,2431],{"__ignoreMap":1145},[1149,2369,2370],{"class":1151,"line":1152},[1149,2371,2372],{},"abstract class Gripper\n",[1149,2374,2375],{"class":1151,"line":1158},[1149,2376,1161],{},[1149,2378,2379],{"class":1151,"line":1164},[1149,2380,1167],{},[1149,2382,2383],{"class":1151,"line":1170},[1149,2384,1174],{"emptyLinePlaceholder":1173},[1149,2386,2387],{"class":1151,"line":1177},[1149,2388,2389],{},"    public Gripper(String name)\n",[1149,2391,2392],{"class":1151,"line":1183},[1149,2393,1697],{},[1149,2395,2396],{"class":1151,"line":1189},[1149,2397,1702],{},[1149,2399,2400],{"class":1151,"line":1195},[1149,2401,1707],{},[1149,2403,2404],{"class":1151,"line":1200},[1149,2405,1174],{"emptyLinePlaceholder":1173},[1149,2407,2408],{"class":1151,"line":1206},[1149,2409,1716],{},[1149,2411,2412],{"class":1151,"line":1719},[1149,2413,1697],{},[1149,2415,2416],{"class":1151,"line":1724},[1149,2417,1727],{},[1149,2419,2420],{"class":1151,"line":1730},[1149,2421,1707],{},[1149,2423,2424],{"class":1151,"line":1735},[1149,2425,1174],{"emptyLinePlaceholder":1173},[1149,2427,2428],{"class":1151,"line":1740},[1149,2429,2430],{},"    public abstract void grab();\n",[1149,2432,2433],{"class":1151,"line":1746},[1149,2434,1209],{},[1085,2436,2437],{},"Which statement is true?",[1085,2439,2440],{},[1125,2441,2442],{},"Options:",[1349,2444,2445,2455,2469,2476],{},[1352,2446,2447,2448,2451,2452],{},"A. ",[1089,2449,2450],{},"Gripper g = new Gripper(\"Claw\");"," compiles, as long as the code never calls ",[1089,2453,2454],{},"g.grab()",[1352,2456,2457,2458,2461,2462,2465,2466,2468],{},"B. ",[1089,2459,2460],{},"class Claw extends Gripper"," compiles without writing ",[1089,2463,2464],{},"grab()",", and inherits an empty ",[1089,2467,2464],{}," that does nothing",[1352,2470,2471,2472,2475],{},"C. ",[1089,2473,2474],{},"Gripper"," isn't allowed to have a constructor, since it can never be instantiated",[1352,2477,2478,2479,2481,2482,2485,2486,2488],{},"D. A subclass that calls ",[1089,2480,1378],{}," in its constructor and implements ",[1089,2483,2484],{},"public void grab()"," can be instantiated, and a ",[1089,2487,2474],{}," variable can hold it",[1085,2490,2491,2494],{},[1125,2492,2493],{},"Answer:"," D",[1085,2496,2497,2500,2501,2503,2504,2506,2507,2509,2510,1485,2513,2515,2516,2518],{},[1125,2498,2499],{},"Why:"," A concrete subclass has to do two things: run ",[1089,2502,2474],{},"'s constructor through ",[1089,2505,1524],{},", and give every inherited abstract method a body. A subclass that does both can be built with ",[1089,2508,1131],{},", and since every such object ",[1332,2511,2512],{},"is a",[1089,2514,2474],{},", a ",[1089,2517,2474],{},"-typed variable can hold it.",[1349,2520,2521,2530,2537],{},[1352,2522,2523,2524,2526,2527,1113],{},"A is wrong — an abstract class can never be instantiated with ",[1089,2525,1131],{},", whether or not its abstract methods are ever called. The compiler rejects the line itself: ",[1089,2528,2529],{},"Gripper is abstract; cannot be instantiated",[1352,2531,2532,2533,2536],{},"B is wrong — an abstract method isn't an empty method that gets inherited. A concrete subclass must implement it, or the class doesn't compile (the only alternative is declaring ",[1089,2534,2535],{},"Claw"," abstract too).",[1352,2538,2539,2540,2542,2543,2545,2546,1113],{},"C is wrong — abstract classes can have constructors, and ",[1089,2541,2474],{}," does. It runs for every subclass object, called through ",[1089,2544,1378],{},"; it just can't be called with ",[1089,2547,2548],{},"new Gripper(...)",[1080,2550,2552],{"id":2551},"micro-parsons","Micro-Parsons",[1085,2554,2555,2558,2559,2562,2563,2565,2566,2568,2569,2572,2573,2576,2577,2580,2581,2583,2584,2586,2587,2589,2590,1113],{},[1125,2556,2557],{},"Problem:"," Every shot the robot takes is announced the same way, but each kind of shot fires differently. Given the program below, with the ",[1089,2560,2561],{},"Shot"," class missing, reorder the fragments into the ",[1089,2564,2561],{}," class that goes where the comment is. ",[1089,2567,2561],{}," must be an abstract class with a concrete ",[1089,2570,2571],{},"announce()"," method that prints ",[1089,2574,2575],{},"Shooting...",", followed by an abstract ",[1089,2578,2579],{},"fire()"," method — write ",[1089,2582,2571],{}," first, then ",[1089,2585,2579],{},". The program should print ",[1089,2588,2575],{}," and then ",[1089,2591,2592],{},"High shot: hood up, flywheel at full speed",[1140,2594,2596],{"className":1142,"code":2595,"language":1144,"meta":1145,"style":1145},"public class ShotTest\n{\n    public static void main(String[] args)\n    {\n        HighShot shot = new HighShot();\n        shot.announce();\n        shot.fire();\n    }\n}\n\n\u002F\u002F Shot class goes here\n\nclass HighShot extends Shot\n{\n    @Override\n    public void fire()\n    {\n        System.out.println(\"High shot: hood up, flywheel at full speed\");\n    }\n}\n",[1089,2597,2598,2603,2607,2611,2615,2620,2625,2630,2634,2638,2642,2647,2651,2656,2660,2664,2669,2673,2678,2682],{"__ignoreMap":1145},[1149,2599,2600],{"class":1151,"line":1152},[1149,2601,2602],{},"public class ShotTest\n",[1149,2604,2605],{"class":1151,"line":1158},[1149,2606,1161],{},[1149,2608,2609],{"class":1151,"line":1164},[1149,2610,1937],{},[1149,2612,2613],{"class":1151,"line":1170},[1149,2614,1697],{},[1149,2616,2617],{"class":1151,"line":1177},[1149,2618,2619],{},"        HighShot shot = new HighShot();\n",[1149,2621,2622],{"class":1151,"line":1183},[1149,2623,2624],{},"        shot.announce();\n",[1149,2626,2627],{"class":1151,"line":1189},[1149,2628,2629],{},"        shot.fire();\n",[1149,2631,2632],{"class":1151,"line":1195},[1149,2633,1707],{},[1149,2635,2636],{"class":1151,"line":1200},[1149,2637,1209],{},[1149,2639,2640],{"class":1151,"line":1206},[1149,2641,1174],{"emptyLinePlaceholder":1173},[1149,2643,2644],{"class":1151,"line":1719},[1149,2645,2646],{},"\u002F\u002F Shot class goes here\n",[1149,2648,2649],{"class":1151,"line":1724},[1149,2650,1174],{"emptyLinePlaceholder":1173},[1149,2652,2653],{"class":1151,"line":1730},[1149,2654,2655],{},"class HighShot extends Shot\n",[1149,2657,2658],{"class":1151,"line":1735},[1149,2659,1161],{},[1149,2661,2662],{"class":1151,"line":1740},[1149,2663,1304],{},[1149,2665,2666],{"class":1151,"line":1746},[1149,2667,2668],{},"    public void fire()\n",[1149,2670,2671],{"class":1151,"line":1850},[1149,2672,1697],{},[1149,2674,2675],{"class":1151,"line":1856},[1149,2676,2677],{},"        System.out.println(\"High shot: hood up, flywheel at full speed\");\n",[1149,2679,2680],{"class":1151,"line":1861},[1149,2681,1707],{},[1149,2683,2684],{"class":1151,"line":1867},[1149,2685,1209],{},[1085,2687,2688],{},"Reorder the fragments below to complete it:",[1349,2690,2691,2697,2703,2709,2715,2721,2727,2733],{},[1352,2692,2693,2694],{},"a. ",[1089,2695,2696],{},"    public abstract void fire();",[1352,2698,2699,2700],{},"b. ",[1089,2701,2702],{},"{",[1352,2704,2705,2706],{},"c. ",[1089,2707,2708],{},"        System.out.println(\"Shooting...\");",[1352,2710,2711,2712],{},"d. ",[1089,2713,2714],{},"abstract class Shot",[1352,2716,2717,2718],{},"e. ",[1089,2719,2720],{},"    }",[1352,2722,2723,2724],{},"f. ",[1089,2725,2726],{},"    public void announce()",[1352,2728,2729,2730],{},"g. ",[1089,2731,2732],{},"}",[1352,2734,2735,2736],{},"h. ",[1089,2737,2738],{},"    {",[1085,2740,2741,2743],{},[1125,2742,2493],{}," d, b, f, h, c, e, a, g",[1140,2745,2747],{"className":1142,"code":2746,"language":1144,"meta":1145,"style":1145},"public class ShotTest\n{\n    public static void main(String[] args)\n    {\n        HighShot shot = new HighShot();\n        shot.announce();\n        shot.fire();\n    }\n}\n\nabstract class Shot\n{\n    public void announce()\n    {\n        System.out.println(\"Shooting...\");\n    }\n    public abstract void fire();\n}\n\nclass HighShot extends Shot\n{\n    @Override\n    public void fire()\n    {\n        System.out.println(\"High shot: hood up, flywheel at full speed\");\n    }\n}\n",[1089,2748,2749,2753,2757,2761,2765,2769,2773,2777,2781,2785,2789,2794,2798,2803,2807,2812,2816,2821,2825,2829,2833,2837,2841,2845,2849,2853,2857],{"__ignoreMap":1145},[1149,2750,2751],{"class":1151,"line":1152},[1149,2752,2602],{},[1149,2754,2755],{"class":1151,"line":1158},[1149,2756,1161],{},[1149,2758,2759],{"class":1151,"line":1164},[1149,2760,1937],{},[1149,2762,2763],{"class":1151,"line":1170},[1149,2764,1697],{},[1149,2766,2767],{"class":1151,"line":1177},[1149,2768,2619],{},[1149,2770,2771],{"class":1151,"line":1183},[1149,2772,2624],{},[1149,2774,2775],{"class":1151,"line":1189},[1149,2776,2629],{},[1149,2778,2779],{"class":1151,"line":1195},[1149,2780,1707],{},[1149,2782,2783],{"class":1151,"line":1200},[1149,2784,1209],{},[1149,2786,2787],{"class":1151,"line":1206},[1149,2788,1174],{"emptyLinePlaceholder":1173},[1149,2790,2791],{"class":1151,"line":1719},[1149,2792,2793],{},"abstract class Shot\n",[1149,2795,2796],{"class":1151,"line":1724},[1149,2797,1161],{},[1149,2799,2800],{"class":1151,"line":1730},[1149,2801,2802],{},"    public void announce()\n",[1149,2804,2805],{"class":1151,"line":1735},[1149,2806,1697],{},[1149,2808,2809],{"class":1151,"line":1740},[1149,2810,2811],{},"        System.out.println(\"Shooting...\");\n",[1149,2813,2814],{"class":1151,"line":1746},[1149,2815,1707],{},[1149,2817,2818],{"class":1151,"line":1850},[1149,2819,2820],{},"    public abstract void fire();\n",[1149,2822,2823],{"class":1151,"line":1856},[1149,2824,1209],{},[1149,2826,2827],{"class":1151,"line":1861},[1149,2828,1174],{"emptyLinePlaceholder":1173},[1149,2830,2831],{"class":1151,"line":1867},[1149,2832,2655],{},[1149,2834,2835],{"class":1151,"line":1872},[1149,2836,1161],{},[1149,2838,2839],{"class":1151,"line":1877},[1149,2840,1304],{},[1149,2842,2843],{"class":1151,"line":1882},[1149,2844,2668],{},[1149,2846,2847],{"class":1151,"line":1887},[1149,2848,1697],{},[1149,2850,2851],{"class":1151,"line":1892},[1149,2852,2677],{},[1149,2854,2855],{"class":1151,"line":1898},[1149,2856,1707],{},[1149,2858,2859],{"class":1151,"line":1903},[1149,2860,1209],{},[1085,2862,2863,2866,2867,2870,2871,2873,2874,2876,2877,2880,2881,2883,2884,2887,2888,2891,2892,2895,2896,2899,2900,2903,2904,2895,2906,2909,2910,2913,2914,2917,2918,2920,2921,2923],{},[1125,2864,2865],{},"Why this order:"," The class declaration (",[1089,2868,2869],{},"d",") comes first — ",[1089,2872,1112],{}," goes right in it, because ",[1089,2875,2561],{}," declares an abstract method and can't be instantiated — followed by the class's opening brace (",[1089,2878,2879],{},"b","). The concrete ",[1089,2882,2571],{}," method comes next, as the Problem asks: its signature (",[1089,2885,2886],{},"f","), opening brace (",[1089,2889,2890],{},"h","), ",[1089,2893,2894],{},"println"," (",[1089,2897,2898],{},"c","), and closing brace (",[1089,2901,2902],{},"e","). Then the abstract ",[1089,2905,2579],{},[1089,2907,2908],{},"a","): a signature ending in a semicolon, with no braces and no body, because each subclass supplies its own. The class's closing brace (",[1089,2911,2912],{},"g",") comes last. ",[1089,2915,2916],{},"HighShot"," isn't abstract, so it must implement ",[1089,2919,2579],{}," — which it does — and it inherits ",[1089,2922,2571],{}," unchanged.",[1080,2925,2927],{"id":2926},"coding","Coding",[1085,2929,2930,2933],{},[1125,2931,2932],{},"Mode:"," full-program",[1085,2935,2936,2938,2939,2941,2942,2944],{},[1125,2937,2557],{}," On this robot there is no such thing as \"just a part\", so make ",[1089,2940,1091],{}," an\n",[1125,2943,1112],{}," class. Write all three classes:",[1349,2946,2947,2971,2985],{},[1352,2948,2949,2951,2952,2954,2955,2957,2958,2572,2961,2964,2965,2967,2968,1113],{},[1089,2950,1091],{}," is abstract. It keeps the private ",[1089,2953,1363],{},", has a constructor taking the name, a\n",[1089,2956,1390],{}," method, a ",[1089,2959,2960],{},"log(String msg)",[1089,2962,2963],{},"[name] msg",", and an ",[1125,2966,1112],{},"\nmethod ",[1089,2969,2970],{},"public abstract void stop()",[1352,2972,2973,2975,2976,2978,2979,2981,2982,1113],{},[1089,2974,1319],{}," extends ",[1089,2977,1091],{},". Its ",[1089,2980,1102],{}," logs ",[1089,2983,2984],{},"rollers off",[1352,2986,2987,2975,2990,2978,2992,2981,2994,1113],{},[1089,2988,2989],{},"Climber",[1089,2991,1091],{},[1089,2993,1102],{},[1089,2995,2996],{},"brake engaged",[1085,2998,2999,3000,3002,3003,3005,3006,1772],{},"Both subclasses need a constructor that takes the name and passes it up. The fixed ",[1089,3001,2200],{}," builds\nan array of ",[1089,3004,1091],{},", stops every part, then prints a count. For the input\n",[1089,3007,3008],{},"3 intake Front climber Left intake Back",[1140,3010,3013],{"className":3011,"code":3012,"language":2226,"meta":1145},[2224],"[Front] rollers off\n[Left] brake engaged\n[Back] rollers off\n3 parts stopped\n",[1089,3014,3012],{"__ignoreMap":1145},[1085,3016,3017],{},[1125,3018,3019],{},"Starter:",[1140,3021,3023],{"className":1142,"code":3022,"language":1144,"meta":1145,"style":1145},"import java.util.*;\n\npublic class Main\n{\n    \u002F\u002F Don't change main\n    public static void main(String[] args)\n    {\n        Scanner in = new Scanner(System.in);\n        int count = in.nextInt();\n        RobotPart[] parts = new RobotPart[count];\n        for (int i = 0; i \u003C count; i++)\n        {\n            String kind = in.next();\n            String name = in.next();\n            if (kind.equals(\"intake\"))\n            {\n                parts[i] = new Intake(name);\n            }\n            else\n            {\n                parts[i] = new Climber(name);\n            }\n        }\n        for (RobotPart p : parts)\n        {\n            p.stop();\n        }\n        System.out.println(parts.length + \" parts stopped\");\n    }\n}\n\nclass RobotPart\n{\n    \u002F\u002F TODO: make this class abstract; the name field, constructor, getName(), log(),\n    \u002F\u002F and an abstract stop()\n}\n\nclass Intake\n{\n    \u002F\u002F TODO: extend RobotPart, with a constructor and its own stop()\n}\n\nclass Climber\n{\n    \u002F\u002F TODO: extend RobotPart, with a constructor and its own stop()\n}\n",[1089,3024,3025,3030,3034,3039,3043,3048,3052,3056,3061,3066,3071,3076,3080,3085,3090,3095,3100,3105,3110,3115,3119,3124,3128,3132,3137,3141,3146,3150,3155,3159,3163,3167,3172,3176,3181,3186,3190,3194,3199,3203,3208,3212,3216,3221,3225,3229],{"__ignoreMap":1145},[1149,3026,3027],{"class":1151,"line":1152},[1149,3028,3029],{},"import java.util.*;\n",[1149,3031,3032],{"class":1151,"line":1158},[1149,3033,1174],{"emptyLinePlaceholder":1173},[1149,3035,3036],{"class":1151,"line":1164},[1149,3037,3038],{},"public class Main\n",[1149,3040,3041],{"class":1151,"line":1170},[1149,3042,1161],{},[1149,3044,3045],{"class":1151,"line":1177},[1149,3046,3047],{},"    \u002F\u002F Don't change main\n",[1149,3049,3050],{"class":1151,"line":1183},[1149,3051,1937],{},[1149,3053,3054],{"class":1151,"line":1189},[1149,3055,1697],{},[1149,3057,3058],{"class":1151,"line":1195},[1149,3059,3060],{},"        Scanner in = new Scanner(System.in);\n",[1149,3062,3063],{"class":1151,"line":1200},[1149,3064,3065],{},"        int count = in.nextInt();\n",[1149,3067,3068],{"class":1151,"line":1206},[1149,3069,3070],{},"        RobotPart[] parts = new RobotPart[count];\n",[1149,3072,3073],{"class":1151,"line":1719},[1149,3074,3075],{},"        for (int i = 0; i \u003C count; i++)\n",[1149,3077,3078],{"class":1151,"line":1724},[1149,3079,1960],{},[1149,3081,3082],{"class":1151,"line":1730},[1149,3083,3084],{},"            String kind = in.next();\n",[1149,3086,3087],{"class":1151,"line":1735},[1149,3088,3089],{},"            String name = in.next();\n",[1149,3091,3092],{"class":1151,"line":1740},[1149,3093,3094],{},"            if (kind.equals(\"intake\"))\n",[1149,3096,3097],{"class":1151,"line":1746},[1149,3098,3099],{},"            {\n",[1149,3101,3102],{"class":1151,"line":1850},[1149,3103,3104],{},"                parts[i] = new Intake(name);\n",[1149,3106,3107],{"class":1151,"line":1856},[1149,3108,3109],{},"            }\n",[1149,3111,3112],{"class":1151,"line":1861},[1149,3113,3114],{},"            else\n",[1149,3116,3117],{"class":1151,"line":1867},[1149,3118,3099],{},[1149,3120,3121],{"class":1151,"line":1872},[1149,3122,3123],{},"                parts[i] = new Climber(name);\n",[1149,3125,3126],{"class":1151,"line":1877},[1149,3127,3109],{},[1149,3129,3130],{"class":1151,"line":1882},[1149,3131,1975],{},[1149,3133,3134],{"class":1151,"line":1887},[1149,3135,3136],{},"        for (RobotPart p : parts)\n",[1149,3138,3139],{"class":1151,"line":1892},[1149,3140,1960],{},[1149,3142,3143],{"class":1151,"line":1898},[1149,3144,3145],{},"            p.stop();\n",[1149,3147,3148],{"class":1151,"line":1903},[1149,3149,1975],{},[1149,3151,3152],{"class":1151,"line":2042},[1149,3153,3154],{},"        System.out.println(parts.length + \" parts stopped\");\n",[1149,3156,3157],{"class":1151,"line":2047},[1149,3158,1707],{},[1149,3160,3161],{"class":1151,"line":2052},[1149,3162,1209],{},[1149,3164,3165],{"class":1151,"line":2057},[1149,3166,1174],{"emptyLinePlaceholder":1173},[1149,3168,3169],{"class":1151,"line":2062},[1149,3170,3171],{},"class RobotPart\n",[1149,3173,3174],{"class":1151,"line":2067},[1149,3175,1161],{},[1149,3177,3178],{"class":1151,"line":2072},[1149,3179,3180],{},"    \u002F\u002F TODO: make this class abstract; the name field, constructor, getName(), log(),\n",[1149,3182,3183],{"class":1151,"line":2077},[1149,3184,3185],{},"    \u002F\u002F and an abstract stop()\n",[1149,3187,3188],{"class":1151,"line":2082},[1149,3189,1209],{},[1149,3191,3192],{"class":1151,"line":2087},[1149,3193,1174],{"emptyLinePlaceholder":1173},[1149,3195,3196],{"class":1151,"line":2092},[1149,3197,3198],{},"class Intake\n",[1149,3200,3201],{"class":1151,"line":2097},[1149,3202,1161],{},[1149,3204,3205],{"class":1151,"line":2102},[1149,3206,3207],{},"    \u002F\u002F TODO: extend RobotPart, with a constructor and its own stop()\n",[1149,3209,3210],{"class":1151,"line":2107},[1149,3211,1209],{},[1149,3213,3214],{"class":1151,"line":2112},[1149,3215,1174],{"emptyLinePlaceholder":1173},[1149,3217,3218],{"class":1151,"line":2117},[1149,3219,3220],{},"class Climber\n",[1149,3222,3223],{"class":1151,"line":2122},[1149,3224,1161],{},[1149,3226,3227],{"class":1151,"line":2127},[1149,3228,3207],{},[1149,3230,3231],{"class":1151,"line":2132},[1149,3232,1209],{},[1085,3234,3235],{},[1125,3236,3237],{},"Scenario 1 (visible):",[1085,3239,3240],{},[1125,3241,3242],{},"Input:",[1140,3244,3247],{"className":3245,"code":3246,"language":2226,"meta":1145},[2224],"3 intake Front climber Left intake Back\n",[1089,3248,3246],{"__ignoreMap":1145},[1085,3250,3251],{},[1125,3252,3253],{},"Expected output:",[1140,3255,3257],{"className":3256,"code":3012,"language":2226,"meta":1145},[2224],[1089,3258,3012],{"__ignoreMap":1145},[1085,3260,3261],{},[1125,3262,3263],{},"Scenario 2 (visible):",[1085,3265,3266],{},[1125,3267,3242],{},[1140,3269,3272],{"className":3270,"code":3271,"language":2226,"meta":1145},[2224],"1 climber Hook\n",[1089,3273,3271],{"__ignoreMap":1145},[1085,3275,3276],{},[1125,3277,3253],{},[1140,3279,3282],{"className":3280,"code":3281,"language":2226,"meta":1145},[2224],"[Hook] brake engaged\n1 parts stopped\n",[1089,3283,3281],{"__ignoreMap":1145},[1085,3285,3286],{},[1125,3287,3288],{},"Scenario 3 (hidden):",[1085,3290,3291],{},[1125,3292,3242],{},[1140,3294,3297],{"className":3295,"code":3296,"language":2226,"meta":1145},[2224],"2 climber Left climber Right\n",[1089,3298,3296],{"__ignoreMap":1145},[1085,3300,3301],{},[1125,3302,3253],{},[1140,3304,3307],{"className":3305,"code":3306,"language":2226,"meta":1145},[2224],"[Left] brake engaged\n[Right] brake engaged\n2 parts stopped\n",[1089,3308,3306],{"__ignoreMap":1145},[1085,3310,3311],{},[1125,3312,3313],{},"Scenario 4 (hidden):",[1085,3315,3316],{},[1125,3317,3242],{},[1140,3319,3322],{"className":3320,"code":3321,"language":2226,"meta":1145},[2224],"4 climber A intake B climber C intake D\n",[1089,3323,3321],{"__ignoreMap":1145},[1085,3325,3326],{},[1125,3327,3253],{},[1140,3329,3332],{"className":3330,"code":3331,"language":2226,"meta":1145},[2224],"[A] brake engaged\n[B] rollers off\n[C] brake engaged\n[D] rollers off\n4 parts stopped\n",[1089,3333,3331],{"__ignoreMap":1145},[1085,3335,3336],{},[1125,3337,3338],{},"Scenario 5 (hidden):",[1085,3340,3341],{},[1125,3342,3242],{},[1140,3344,3347],{"className":3345,"code":3346,"language":2226,"meta":1145},[2224],"0\n",[1089,3348,3346],{"__ignoreMap":1145},[1085,3350,3351],{},[1125,3352,3253],{},[1140,3354,3357],{"className":3355,"code":3356,"language":2226,"meta":1145},[2224],"0 parts stopped\n",[1089,3358,3356],{"__ignoreMap":1145},[1085,3360,3361],{},[1125,3362,3363],{},"Solution:",[1140,3365,3367],{"className":1142,"code":3366,"language":1144,"meta":1145,"style":1145},"import java.util.*;\n\npublic class Main\n{\n    \u002F\u002F Don't change main\n    public static void main(String[] args)\n    {\n        Scanner in = new Scanner(System.in);\n        int count = in.nextInt();\n        RobotPart[] parts = new RobotPart[count];\n        for (int i = 0; i \u003C count; i++)\n        {\n            String kind = in.next();\n            String name = in.next();\n            if (kind.equals(\"intake\"))\n            {\n                parts[i] = new Intake(name);\n            }\n            else\n            {\n                parts[i] = new Climber(name);\n            }\n        }\n        for (RobotPart p : parts)\n        {\n            p.stop();\n        }\n        System.out.println(parts.length + \" parts stopped\");\n    }\n}\n\nabstract class RobotPart\n{\n    private String name;\n\n    public RobotPart(String name) { this.name = name; }\n    public String getName() { return name; }\n    public void log(String msg) { System.out.println(\"[\" + name + \"] \" + msg); }\n\n    public abstract void stop();\n}\n\nclass Intake extends RobotPart\n{\n    public Intake(String name) { super(name); }\n\n    @Override\n    public void stop() { log(\"rollers off\"); }\n}\n\nclass Climber extends RobotPart\n{\n    public Climber(String name) { super(name); }\n\n    @Override\n    public void stop() { log(\"brake engaged\"); }\n}\n",[1089,3368,3369,3373,3377,3381,3385,3389,3393,3397,3401,3405,3409,3413,3417,3421,3425,3429,3433,3437,3441,3445,3449,3453,3457,3461,3465,3469,3473,3477,3481,3485,3489,3493,3498,3502,3506,3510,3514,3518,3522,3526,3531,3535,3539,3544,3548,3552,3556,3560,3564,3568,3572,3577,3581,3586,3590,3594,3599],{"__ignoreMap":1145},[1149,3370,3371],{"class":1151,"line":1152},[1149,3372,3029],{},[1149,3374,3375],{"class":1151,"line":1158},[1149,3376,1174],{"emptyLinePlaceholder":1173},[1149,3378,3379],{"class":1151,"line":1164},[1149,3380,3038],{},[1149,3382,3383],{"class":1151,"line":1170},[1149,3384,1161],{},[1149,3386,3387],{"class":1151,"line":1177},[1149,3388,3047],{},[1149,3390,3391],{"class":1151,"line":1183},[1149,3392,1937],{},[1149,3394,3395],{"class":1151,"line":1189},[1149,3396,1697],{},[1149,3398,3399],{"class":1151,"line":1195},[1149,3400,3060],{},[1149,3402,3403],{"class":1151,"line":1200},[1149,3404,3065],{},[1149,3406,3407],{"class":1151,"line":1206},[1149,3408,3070],{},[1149,3410,3411],{"class":1151,"line":1719},[1149,3412,3075],{},[1149,3414,3415],{"class":1151,"line":1724},[1149,3416,1960],{},[1149,3418,3419],{"class":1151,"line":1730},[1149,3420,3084],{},[1149,3422,3423],{"class":1151,"line":1735},[1149,3424,3089],{},[1149,3426,3427],{"class":1151,"line":1740},[1149,3428,3094],{},[1149,3430,3431],{"class":1151,"line":1746},[1149,3432,3099],{},[1149,3434,3435],{"class":1151,"line":1850},[1149,3436,3104],{},[1149,3438,3439],{"class":1151,"line":1856},[1149,3440,3109],{},[1149,3442,3443],{"class":1151,"line":1861},[1149,3444,3114],{},[1149,3446,3447],{"class":1151,"line":1867},[1149,3448,3099],{},[1149,3450,3451],{"class":1151,"line":1872},[1149,3452,3123],{},[1149,3454,3455],{"class":1151,"line":1877},[1149,3456,3109],{},[1149,3458,3459],{"class":1151,"line":1882},[1149,3460,1975],{},[1149,3462,3463],{"class":1151,"line":1887},[1149,3464,3136],{},[1149,3466,3467],{"class":1151,"line":1892},[1149,3468,1960],{},[1149,3470,3471],{"class":1151,"line":1898},[1149,3472,3145],{},[1149,3474,3475],{"class":1151,"line":1903},[1149,3476,1975],{},[1149,3478,3479],{"class":1151,"line":2042},[1149,3480,3154],{},[1149,3482,3483],{"class":1151,"line":2047},[1149,3484,1707],{},[1149,3486,3487],{"class":1151,"line":2052},[1149,3488,1209],{},[1149,3490,3491],{"class":1151,"line":2057},[1149,3492,1174],{"emptyLinePlaceholder":1173},[1149,3494,3495],{"class":1151,"line":2062},[1149,3496,3497],{},"abstract class RobotPart\n",[1149,3499,3500],{"class":1151,"line":2067},[1149,3501,1161],{},[1149,3503,3504],{"class":1151,"line":2072},[1149,3505,1167],{},[1149,3507,3508],{"class":1151,"line":2077},[1149,3509,1174],{"emptyLinePlaceholder":1173},[1149,3511,3512],{"class":1151,"line":2082},[1149,3513,1180],{},[1149,3515,3516],{"class":1151,"line":2087},[1149,3517,1186],{},[1149,3519,3520],{"class":1151,"line":2092},[1149,3521,1192],{},[1149,3523,3524],{"class":1151,"line":2097},[1149,3525,1174],{"emptyLinePlaceholder":1173},[1149,3527,3528],{"class":1151,"line":2102},[1149,3529,3530],{},"    public abstract void stop();\n",[1149,3532,3533],{"class":1151,"line":2107},[1149,3534,1209],{},[1149,3536,3537],{"class":1151,"line":2112},[1149,3538,1174],{"emptyLinePlaceholder":1173},[1149,3540,3541],{"class":1151,"line":2117},[1149,3542,3543],{},"class Intake extends RobotPart\n",[1149,3545,3546],{"class":1151,"line":2122},[1149,3547,1161],{},[1149,3549,3550],{"class":1151,"line":2127},[1149,3551,1295],{},[1149,3553,3554],{"class":1151,"line":2132},[1149,3555,1174],{"emptyLinePlaceholder":1173},[1149,3557,3558],{"class":1151,"line":2137},[1149,3559,1304],{},[1149,3561,3562],{"class":1151,"line":2142},[1149,3563,1309],{},[1149,3565,3566],{"class":1151,"line":2147},[1149,3567,1209],{},[1149,3569,3570],{"class":1151,"line":2152},[1149,3571,1174],{"emptyLinePlaceholder":1173},[1149,3573,3574],{"class":1151,"line":2157},[1149,3575,3576],{},"class Climber extends RobotPart\n",[1149,3578,3579],{"class":1151,"line":2162},[1149,3580,1161],{},[1149,3582,3583],{"class":1151,"line":2167},[1149,3584,3585],{},"    public Climber(String name) { super(name); }\n",[1149,3587,3588],{"class":1151,"line":2172},[1149,3589,1174],{"emptyLinePlaceholder":1173},[1149,3591,3592],{"class":1151,"line":2177},[1149,3593,1304],{},[1149,3595,3596],{"class":1151,"line":2182},[1149,3597,3598],{},"    public void stop() { log(\"brake engaged\"); }\n",[1149,3600,3601],{"class":1151,"line":2187},[1149,3602,1209],{},[1085,3604,3605,1485,3607,3609,3610,3612,3613,3615,3616,3618,3619,3621,3622,3624,3625,3627,3628,1565,3630,3633,3634,3636],{},[1125,3606,2499],{},[1089,3608,1112],{}," on the class means ",[1089,3611,1382],{}," no longer compiles, but ",[1089,3614,1091],{},"\nstill works as the array's element type, and still has a field, a constructor (run by each\nsubclass's ",[1089,3617,1378],{},"), and concrete methods. ",[1089,3620,1102],{}," is only a signature ending in ",[1089,3623,1506],{},", so each\nconcrete subclass has to write its own body, and the compiler rejects a subclass that forgets.\nBecause every element is really an ",[1089,3626,1319],{}," or a ",[1089,3629,2989],{},[1089,3631,3632],{},"p.stop()"," in ",[1089,3635,2200],{}," is always safe, and\nruns that class's own version.",[1577,3638,1579],{},{"title":1145,"searchDepth":1158,"depth":1158,"links":3640},[3641,3642,3643],{"id":2355,"depth":1158,"text":2356},{"id":2551,"depth":1158,"text":2552},{"id":2926,"depth":1158,"text":2927},{"outlineRef":1593,"pairsWith":2342,"status":3645},"new — authored exercises (Multiple Choice + Micro-Parsons + Coding)",{"title":972,"description":1145},"E4EyQLCWYgGihTKHg9axdOugkX5_R3-An0oYgd6CDNY",1792718166132]