A marker annotation : Annotations Types « Language « Java Tutorial

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.reflect.Method;

@interface MyMarker {

class Marker {
  public static void myMeth() {
    Marker ob = new Marker();

    try {
      Method m = ob.getClass().getMethod("myMeth");

      if (m.isAnnotationPresent(MyMarker.class))
        System.out.println("MyMarker is present.");

    } catch (NoSuchMethodException exc) {
      System.out.println("Method Not Found.");

  public static void main(String args[]) {

1.13.Annotations Types
1.13.1.Annotations and Annotation Types
1.13.2.The Annotation Interface
1.13.3.Using Default Values
1.13.4.Marker Annotations
1.13.5.Single-Member Annotations
1.13.6.Creates and uses a single-member annotation
1.13.7.The single-value syntax
1.13.8.Some Restrictions
1.13.9.A marker annotation