CGLib动态代理

1.相关jar包

cglib-2.2.jar
cglib-nodep-2.2.jar
asm-3.3.1.jar

2.定义Hello接口

public interface Hello {

    void say(String name);
}

3.Hello接口实现类

public class HelloImpl implements Hello{

    @Override
    public void say(String name) {
        System.out.println("Hello"+name);
    }

}

4.CGLib代理类

import java.lang.reflect.Method;
import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;

public class CGLibProxy implements MethodInterceptor{

    private static CGLibProxy instance = new CGLibProxy();

    private CGLibProxy() {}

    public static CGLibProxy getInstance(){
        return instance;
    }

    @SuppressWarnings("unchecked")
    public <T> T getProxy(Class<T> cls){
        return (T) Enhancer.create(cls, this);
    }

    @Override
    public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
        before();
        Object result = proxy.invokeSuper(obj, args);
        after();
        return result;
    }

    private void before() {
        System.out.println("before");
    }

    private void after() {
        System.out.println("after");
    }

}

5.main

public class Main {

    public static void main(String[] args) {

        Hello helloProxy = CGLibProxy.getInstance().getProxy(HelloImpl.class);
        helloProxy.say("ke");
    }
}

参考《架构探险 从零开始写Java Web框架》