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API Help
Stay organized with collections
Save and categorize content based on your preferences.
-
Overview
The Overview page is the front page of this API document and provides a list of all packages with a summary for each. This page can also contain an overall description of the set of packages.
-
Package
Each package has a page that contains a list of its classes and interfaces, with a summary for each. This page can contain six categories:
- Interfaces (italic)
- Classes
- Enums
- Exceptions
- Errors
- Annotation Types
-
Class/Interface
Each class, interface, nested class and nested interface has its own separate page. Each of these pages has three sections consisting of a class/interface description, summary tables, and detailed member descriptions:
- Class inheritance diagram
- Direct Subclasses
- All Known Subinterfaces
- All Known Implementing Classes
- Class/interface declaration
- Class/interface description
- Nested Class Summary
- Field Summary
- Constructor Summary
- Method Summary
- Field Detail
- Constructor Detail
- Method Detail
Each summary entry contains the first sentence from the detailed description for that item. The summary entries are alphabetical, while the detailed descriptions are in the order they appear in the source code. This preserves the logical groupings established by the programmer.
-
Annotation Type
Each annotation type has its own separate page with the following sections:
- Annotation Type declaration
- Annotation Type description
- Required Element Summary
- Optional Element Summary
- Element Detail
-
Enum
Each enum has its own separate page with the following sections:
- Enum declaration
- Enum description
- Enum Constant Summary
- Enum Constant Detail
-
Tree (Class Hierarchy)
There is a Class Hierarchy page for all packages, plus a hierarchy for each package. Each hierarchy page contains a list of classes and a list of interfaces. The classes are organized by inheritance structure starting with java.lang.Object
. The interfaces do not inherit from java.lang.Object
.
- When viewing the Overview page, clicking on "Tree" displays the hierarchy for all packages.
- When viewing a particular package, class or interface page, clicking "Tree" displays the hierarchy for only that package.
-
Deprecated API
The Deprecated API page lists all of the API that have been deprecated. A deprecated API is not recommended for use, generally due to improvements, and a replacement API is usually given. Deprecated APIs may be removed in future implementations.
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Index
The Index contains an alphabetic list of all classes, interfaces, constructors, methods, and fields.
-
Prev/Next
These links take you to the next or previous class, interface, package, or related page.
-
Frames/No Frames
These links show and hide the HTML frames. All pages are available with or without frames.
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All Classes
The All Classes link shows all classes and interfaces except non-static nested types.
-
Each serializable or externalizable class has a description of its serialization fields and methods. This information is of interest to re-implementors, not to developers using the API. While there is no link in the navigation bar, you can get to this information by going to any serialized class and clicking "Serialized Form" in the "See also" section of the class description.
-
Constant Field Values
The Constant Field Values page lists the static final fields and their values.
This help file applies to API documentation generated using the standard doclet.
Except as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 4.0 License, and code samples are licensed under the Apache 2.0 License. For details, see the Google Developers Site Policies. Java is a registered trademark of Oracle and/or its affiliates.
Last updated 2025-06-16 UTC.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-06-16 UTC."],[[["\u003cp\u003eThis API document is organized into pages based on the navigation bar, including Overview, Package, Class/Interface, Annotation Type, Enum, and Tree (Class Hierarchy).\u003c/p\u003e\n"],["\u003cp\u003eEach package page lists its classes and interfaces, along with summaries for each, categorized into Interfaces, Classes, Enums, Exceptions, Errors, and Annotation Types.\u003c/p\u003e\n"],["\u003cp\u003eEach Class/Interface page contains a detailed description, summary tables, and member descriptions, including class inheritance, subclasses, implemented classes and interfaces, field summaries, constructor summaries, and method summaries.\u003c/p\u003e\n"],["\u003cp\u003eThe document provides specialized pages for specific elements like Deprecated APIs, an Index of all elements, and Constant Field Values, alongside navigation aids such as Prev/Next links and Frames/No Frames options.\u003c/p\u003e\n"],["\u003cp\u003eThe Class Hierarchy page shows the inheritance relationships between all classes and the organization of the interfaces, with the classes starting with \u003ccode\u003ejava.lang.Object\u003c/code\u003e and the interfaces independently listed.\u003c/p\u003e\n"]]],[],null,["# API Help\n\nHow This API Document Is Organized\n==================================\n\nThis API (Application Programming Interface) document has pages corresponding to the items in the navigation bar, described as follows. \n-\n\n Overview\n --------\n\n The [Overview](/appengine/docs/legacy/standard/java/tools/localunittesting/javadoc/overview-summary) page is the front page of this API document and provides a list of all packages with a summary for each. This page can also contain an overall description of the set of packages.\n-\n\n Package\n -------\n\n Each package has a page that contains a list of its classes and interfaces, with a summary for each. This page can contain six categories:\n - Interfaces (italic)\n - Classes\n - Enums\n - Exceptions\n - Errors\n - Annotation Types\n-\n\n Class/Interface\n ---------------\n\n Each class, interface, nested class and nested interface has its own separate page. Each of these pages has three sections consisting of a class/interface description, summary tables, and detailed member descriptions:\n - Class inheritance diagram\n - Direct Subclasses\n - All Known Subinterfaces\n - All Known Implementing Classes\n - Class/interface declaration\n - Class/interface description\n\n \u003c!-- --\u003e\n\n - Nested Class Summary\n - Field Summary\n - Constructor Summary\n - Method Summary\n\n \u003c!-- --\u003e\n\n - Field Detail\n - Constructor Detail\n - Method Detail\n\n Each summary entry contains the first sentence from the detailed description for that item. The summary entries are alphabetical, while the detailed descriptions are in the order they appear in the source code. This preserves the logical groupings established by the programmer.\n-\n\n Annotation Type\n ---------------\n\n Each annotation type has its own separate page with the following sections:\n - Annotation Type declaration\n - Annotation Type description\n - Required Element Summary\n - Optional Element Summary\n - Element Detail\n-\n\n Enum\n ----\n\n Each enum has its own separate page with the following sections:\n - Enum declaration\n - Enum description\n - Enum Constant Summary\n - Enum Constant Detail\n-\n\n Tree (Class Hierarchy)\n ----------------------\n\n There is a [Class Hierarchy](/appengine/docs/legacy/standard/java/tools/localunittesting/javadoc/overview-tree) page for all packages, plus a hierarchy for each package. Each hierarchy page contains a list of classes and a list of interfaces. The classes are organized by inheritance structure starting with `java.lang.Object`. The interfaces do not inherit from `java.lang.Object`.\n - When viewing the Overview page, clicking on \"Tree\" displays the hierarchy for all packages.\n - When viewing a particular package, class or interface page, clicking \"Tree\" displays the hierarchy for only that package.\n-\n\n Deprecated API\n --------------\n\n The [Deprecated API](/appengine/docs/legacy/standard/java/tools/localunittesting/javadoc/deprecated-list) page lists all of the API that have been deprecated. A deprecated API is not recommended for use, generally due to improvements, and a replacement API is usually given. Deprecated APIs may be removed in future implementations.\n-\n\n Index\n -----\n\n The [Index](/appengine/docs/legacy/standard/java/tools/localunittesting/javadoc/index-all) contains an alphabetic list of all classes, interfaces, constructors, methods, and fields.\n-\n\n Prev/Next\n ---------\n\n These links take you to the next or previous class, interface, package, or related page.\n-\n\n Frames/No Frames\n ----------------\n\n These links show and hide the HTML frames. All pages are available with or without frames.\n-\n\n All Classes\n -----------\n\n The [All Classes](/appengine/docs/legacy/standard/java/tools/localunittesting/javadoc/allclasses-noframe) link shows all classes and interfaces except non-static nested types.\n-\n\n Serialized Form\n ---------------\n\n Each serializable or externalizable class has a description of its serialization fields and methods. This information is of interest to re-implementors, not to developers using the API. While there is no link in the navigation bar, you can get to this information by going to any serialized class and clicking \"Serialized Form\" in the \"See also\" section of the class description.\n-\n\n Constant Field Values\n ---------------------\n\n The [Constant Field Values](/appengine/docs/legacy/standard/java/tools/localunittesting/javadoc/constant-values) page lists the static final fields and their values.\n\nThis help file applies to API documentation generated using the standard doclet."]]