Annotated.java

package annotations;

import java.lang.reflect.InvocationTargetException;



@TestAnnotation(hoge="fuga")
public class Annotated {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		Class<Annotated> thisClass = Annotated.class;
		TestAnnotation a = thisClass.getAnnotation(TestAnnotation.class);
		Class<TestAnnotation.Fuga> fugaClass = a.logic();

		try {
			TestAnnotation.Fuga fuga = fugaClass.newInstance();
			fugaClass.getMethod("greet").invoke(fuga);
		} catch (SecurityException e) {
			e.printStackTrace();
		} catch (NoSuchMethodException e) {
			e.printStackTrace();
		} catch (InstantiationException e) {
			e.printStackTrace();
		} catch (IllegalAccessException e) {
			e.printStackTrace();
		} catch (IllegalArgumentException e) {
			e.printStackTrace();
		} catch (InvocationTargetException e) {
			e.printStackTrace();
		}

		System.out.println("hoge");
	}

}

TestAnnotation.java

package annotations;

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

@Retention(RetentionPolicy.RUNTIME)
public @interface TestAnnotation {
	String hoge() default "hoge";
	Class<TestAnnotation.Fuga> logic() default Fuga.class;
	
	public class Fuga {
		public void greet() {
			System.out.println("Hello World!");
		}
	}
}