import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.reflect.Method; public class Annotations { private static void expect(boolean v) { if (! v) throw new RuntimeException(); } public static void main(String[] args) throws Exception { Method m = Annotations.class.getMethod("foo"); expect(m.isAnnotationPresent(Test.class)); expect(((Test) m.getAnnotation(Test.class)).value().equals("couscous")); expect(((TestEnum) m.getAnnotation(TestEnum.class)).value() .equals(Color.Red)); expect(((TestInteger) m.getAnnotation(TestInteger.class)).value() == 42); } @Test("couscous") @TestEnum(Color.Red) @TestInteger(42) public static void foo() { } @Retention(RetentionPolicy.RUNTIME) private @interface Test { public String value(); } @Retention(RetentionPolicy.RUNTIME) private @interface TestEnum { public Color value(); } @Retention(RetentionPolicy.RUNTIME) private @interface TestInteger { public int value(); } private static enum Color { Red, Yellow, Blue } }