使用cglib 实例

package com.ssc.gc.hook;

public interface Hook {
	public void hook();
}

package com.ssc.gc.hook;

import com.ssc.gc.hook.annotation.Surround;

public class ConcreateHook extends AbstractHook{
	
	@Surround
	public void hook(){
		super.hook();
		System.out.println("Concreate Hook run!");
	}
}

package com.ssc.gc.hook;

public interface Trigger {
	public void trigger();
}

package com.ssc.gc.hook;

public class ConcreateTrigger implements Trigger{

	@Override
	public void trigger() {
		
		System.out.println("Concreate Trigger run!");
		
	}

}

package com.ssc.gc.hook;

public class AbstractHook implements Hook{

	Trigger trigger;
	
	@Override
	public void hook() {
		System.out.println("abstractHook speak");
		trigger.trigger();
	}

	public Trigger getTrigger() {
		return trigger;
	}

	public void setTrigger(Trigger trigger) {
		this.trigger = trigger;
	}

}

package com.ssc.gc.hook.annotation;

import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

import java.lang.annotation.Retention;
import java.lang.annotation.Target;

@Retention(RUNTIME)
@Target({ METHOD })
public @interface Surround {
	/**
    *
    */
	String name() default "";

	/**
    *
    */
	boolean required() default true;
}

package com.ssc.gc.hook.cglibproxy;

import java.lang.reflect.Method;

import com.ssc.gc.hook.annotation.Surround;

import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;

public class SurroundAnnoProxy implements MethodInterceptor{

	@Override
	public Object intercept(Object obj, Method method, Object[] args,
			MethodProxy proxy) throws Throwable {
		Surround surround = method.getAnnotation(Surround.class);
		if(surround == null){
			return proxy.invokeSuper(obj, args);
		}
		
		System.out.println("do something after original object call");
		Object result = proxy.invokeSuper(obj, args);
		System.out.println("do something after original object call");
		
		return result;
	}
	
}

package com.ssc.gc.hook;

import java.util.HashSet;
import java.util.Set;

import net.sf.cglib.proxy.Enhancer;

import org.junit.Test;

import cglib.CallBackObj;

import com.ssc.gc.hook.cglibproxy.SurroundAnnoProxy;
import com.ssc.gc.sample.metrics.MetricsMonitorProcessor;

public class HookClient {
	
	public static void main(String[] args) {
		Trigger trigger = new ConcreateTrigger();
		ConcreateHook hook = new ConcreateHook();
		hook.setTrigger(trigger);
		hook.hook();
	}
	
	@Test
	public void test1(){
		Enhancer enhancer = new Enhancer();
		enhancer.setSuperclass(ConcreateHook.class);
		enhancer.setInterfaces(getInterfaces(ConcreateHook.class).toArray(new Class<?>[0]));
		enhancer.setCallback(new SurroundAnnoProxy());
		ConcreateHook mmp = (ConcreateHook)enhancer.create();
		mmp.setTrigger(new ConcreateTrigger());
		mmp.hook();
	}

	private Set<Class<?>> getInterfaces(Class<?> clazz)
	{
		Set<Class<?>> interfaceList = new HashSet<Class<?>>();

		if (clazz.isInterface()) {
			interfaceList.add(clazz);
		}

		Class<?> superClass = clazz.getSuperclass();
		if (superClass != null) {
			interfaceList.addAll(getInterfaces(superClass));
		}

		Class<?>[] superInterfaces = clazz.getInterfaces();
		for (int i = 0; i < superInterfaces.length; i++) {
			Class<?> superInterface = superInterfaces[i];
			interfaceList.addAll(getInterfaces(superInterface));
		}

		return interfaceList;
	}
	
	
}