Added in API level 1

Summary: Methods

Annotation

public interface Annotation

java.lang.annotation.Annotation

Known indirect subclasses CriticalNative, Deprecated, Documented, FastNative, FlakyTest, FunctionalInterface, Generated, Inherited, JavascriptInterface, LargeTest, MediumTest, Native, Override, RemoteViews.RemoteView, Repeatable, and 18 others. CriticalNative An ART runtime built-in optimization for native methods to speed up JNI transitions: Methods that are annotated with @CriticalNative use the fastest available JNI transitions from managed code to the native code and back.  Deprecated A program element annotated @Deprecated is one that programmers are discouraged from using.  Documented If the annotation @Documented is present on the declaration of an annotation interface A, then any @A annotation on an element is considered part of the element's public contract.  FastNative An ART runtime built-in optimization for native methods to speed up JNI transitions: Compared to normal native methods, native methods that are annotated with @FastNative use faster JNI transitions from managed code to the native code and back.  FlakyTest This @interface was deprecated in API level 24. Use FlakyTest instead. New tests should be written using the Android Testing Support Library.  FunctionalInterface An informative annotation type used to indicate that an interface type declaration is intended to be a functional interface as defined by the Java Language Specification.  Generated   Inherited Indicates that an annotation interface is automatically inherited.  JavascriptInterface Annotation that allows exposing methods to JavaScript.  LargeTest This @interface was deprecated in API level 24. Use LargeTest instead. New tests should be written using the Android Testing Support Library.  MediumTest This @interface was deprecated in API level 24. Use MediumTest instead. New tests should be written using the Android Testing Support Library.  Native Indicates that a field defining a constant value may be referenced from native code.  Override Indicates that a method declaration is intended to override a method declaration in a supertype.  RemoteViews.RemoteView This annotation indicates that a subclass of View is allowed to be used with the RemoteViews mechanism.  Repeatable The annotation interface java.lang.annotation.Repeatable is used to indicate that the annotation interface whose declaration it (meta-)annotates is repeatable.  RepetitiveTest This @interface was deprecated in API level Baklava. New tests should be written using the Android Testing Support Library.  Retention Indicates how long annotations with the annotated interface are to be retained.  SafeVarargs A programmer assertion that the body of the annotated method or constructor does not perform potentially unsafe operations on its varargs parameter.  Serial Indicates that an annotated field or method is part of the serialization mechanism defined by the Java Object Serialization Specification.  SmallTest This @interface was deprecated in API level 24. Use SmallTest instead. New tests should be written using the Android Testing Support Library.  Smoke This @interface was deprecated in API level 24. New tests should be written using the Android Testing Support Library.  Suppress This @interface was deprecated in API level 24. Use Suppress instead. New tests should be written using the Android Testing Support Library.  SuppressLint Indicates that Lint should ignore the specified warnings for the annotated element.  SuppressWarnings Indicates that the named compiler warnings should be suppressed in the annotated element (and in all program elements contained in the annotated element).  Target Indicates the contexts in which an annotation interface is applicable.  TargetApi Indicates that Lint should treat this type as targeting a given API level, no matter what the project target is.  TestTarget This @interface was deprecated in API level 14. Obsolete.  TestTargetClass This @interface was deprecated in API level 14. Obsolete.  UiThreadTest This @interface was deprecated in API level 24. Use UiThreadTest instead. New tests should be written using the Android Testing Support Library.  ViewDebug.CapturedViewProperty This annotation can be used to mark fields and methods to be dumped when the view is captured.  ViewDebug.ExportedProperty This annotation can be used to mark fields and methods to be dumped by the view server.  ViewDebug.FlagToString Defines a mapping from a flag to a String.  ViewDebug.IntToString Defines a mapping from an int value to a String.

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The common interface extended by all annotation interfaces. Note that an interface that manually extends this one does not define an annotation interface. Also note that this interface does not itself define an annotation interface. More information about annotation interfaces can be found in section {@jls 9.6} of The Java Language Specification. The AnnotatedElement interface discusses compatibility concerns when evolving an annotation interface from being non-repeatable to being repeatable.

Summary

Public methods
abstract Class<? extends Annotation>	annotationType() Returns the annotation interface of this annotation.
abstract boolean	equals(Object obj) Returns true if the specified object represents an annotation that is logically equivalent to this one.
abstract int	hashCode() Returns the hash code of this annotation.
abstract String	toString() Returns a string representation of this annotation.

Public methods

annotationType

Added in API level 1

public abstract Class<? extends Annotation> annotationType ()

Returns the annotation interface of this annotation.

API Note:

• Implementation-dependent classes are used to provide the implementations of annotations. Therefore, calling getClass on an annotation will return an implementation-dependent class. In contrast, this method will reliably return the annotation interface of the annotation.

Returns
Class<? extends Annotation>	the annotation interface of this annotation

See also:

• Enum.getDeclaringClass()

equals

Added in API level 1

public abstract boolean equals (Object obj)

Returns true if the specified object represents an annotation that is logically equivalent to this one. In other words, returns true if the specified object is an instance of the same annotation interface as this instance, all of whose members are equal to the corresponding member of this annotation, as defined below:

• Two corresponding primitive typed members whose values are x and y are considered equal if x == y, unless their type is float or double.
• Two corresponding float members whose values are x and y are considered equal if Float.valueOf(x).equals(Float.valueOf(y)). (Unlike the == operator, NaN is considered equal to itself, and 0.0f unequal to -0.0f.)
• Two corresponding double members whose values are x and y are considered equal if Double.valueOf(x).equals(Double.valueOf(y)). (Unlike the == operator, NaN is considered equal to itself, and 0.0 unequal to -0.0.)
• Two corresponding String, Class, enum, or annotation typed members whose values are x and y are considered equal if x.equals(y). (Note that this definition is recursive for annotation typed members.)
• Two corresponding array typed members x and y are considered equal if Arrays.equals(x, y), for the appropriate overloading of Arrays.equals.

Parameters
obj	Object

Returns
boolean	true if the specified object represents an annotation that is logically equivalent to this one, otherwise false

hashCode

Added in API level 1

public abstract int hashCode ()

Returns the hash code of this annotation.

The hash code of an annotation is the sum of the hash codes of its members (including those with default values). The hash code of an annotation member is (127 times the hash code of the member-name as computed by String.hashCode()) XOR the hash code of the member-value. The hash code of a member-value depends on its type as defined below:

• The hash code of a primitive value v is equal to WrapperType.valueOf(v).hashCode(), where WrapperType is the wrapper type corresponding to the primitive type of v (Byte, Character, Double, Float, Integer, Long, Short, or Boolean).
• The hash code of a string, enum, class, or annotation member-value v is computed as by calling v.hashCode(). (In the case of annotation member values, this is a recursive definition.)
• The hash code of an array member-value is computed by calling the appropriate overloading of Arrays.hashCode on the value. (There is one overloading for each primitive type, and one for object reference types.)

Returns
int	the hash code of this annotation

toString

Added in API level 1

public abstract String toString ()

Returns a string representation of this annotation. The details of the representation are implementation-dependent, but the following may be regarded as typical:

   @com.example.Name(first="Duke", middle="of", last="Java")
 

Returns
String	a string representation of this annotation