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Custom annotations in Java

  Java Custom annotations  or Java User-defined annotations are easy to create and use. The  @interface  element is used to declare an annotation. Example: @interface  SampleAnnotation{}   Some key points: The method should not have any throws clauses The method should return one of the following: primitive data types, String, Class, enum or array of these data types. The method  should not have any parameters . We should attach @ just before the interface keyword to define annotation. It may assign a default value to the method. There are three types of annotations. 1.  Marker Annotation:   An annotation that has no method, is called marker annotation. For example: @interface  SampleAnnotation{}   The @Override and @Deprecated are marker annotations. 2.  Single-Value Annotation:   An annotation that has one method, is called a single-value annotation.  For example: @interface  SampleAnnotation{...