spring学习笔记cglib

CglibProxyTest.java

package com.lin.test;

import java.lang.reflect.Method;

import org.junit.Test;
import org.springframework.cglib.proxy.Enhancer;
import org.springframework.cglib.proxy.MethodInterceptor;
import org.springframework.cglib.proxy.MethodProxy;
/**
 * CGLIB 拦截器的一个demo
 * @author linfenliang
 *
 */
public class CglibProxyTest {

@Test
public void test() {
UserDao dao = new UserDaoImply();
UserDaoCglibProxy proxy = new UserDaoCglibProxy();
dao =(UserDao) proxy.proxy(dao);
dao.userLogin("linfenliang", "123456");
}

}
abstract class UserDao{
public abstract void userLogin(String username,String password);
}
class UserDaoImply extends UserDao{
@Override
public void userLogin(String username, String password) {
System.out.println("username:".concat(username).concat(",password:").concat(password));
}
}
class UserDaoCglibProxy implements MethodInterceptor{
public Object proxy(Object obj){
Enhancer enhancer = new Enhancer();
enhancer.setSuperclass(obj.getClass());
enhancer.setCallback(this);
return enhancer.create();
}
private boolean checkParamsValid(Object value){
System.out.println("ready to check paramters:"+value);
return value!=null ;
}
private boolean checkResultValid(String value){
System.out.println("check result .");
return value!=null;
}


@Override
public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
checkParamsValid(args[0]);
checkParamsValid(args[1]);
obj = proxy.invokeSuper(obj, args);
checkResultValid(null);
return obj;
}

}