Java in a Nutshell, 5th Edition

Name

Annotation

Synopsis

A type declared with the @interface syntax is an annotation type that implicitly extends this interface. Note that the Annotation interface is not itself an annotation type. Furthermore, if you define an interface (rather than an @interface) that explicitly extends Annotation, the result is not an annotation type either. The only way to define an annotation type is with an @interface definition. When an annotation is queried with the java.lang.reflect.AnnotatedElement API, the object returned implements this interface as well as the interface defined by the specific annotation type.

This interface defines the annotationType( ) method, which returns the Class of the annotation type for any annotation object. It also includes the equals( ) and hashCode( ) methods of Object to require an implementation to compare annotations by the values of their members rather than simply by using = =. Finally, Annotation also overrides the toString( ) method to require implementations to provide some meaningful string representation of an annotation. The format of the returned string is not specified, but you can expect implementations to produce a string using a syntax similar to that used to encode annotations in Java source code.

public interface Annotation {
// Public Instance Methods
     Class<? extends java.lang.annotation.Annotation> annotationType( );  
     boolean equals(Object obj);  
     int hashCode( );  
     String toString( );  
}

Implementations

Deprecated, Override, SuppressWarnings ...