Spring中的两种代理JDK和CGLIB的区别浅谈

package com.fy.spring.proxy;    
public interface UserManager {  
  public void addUser(String id, String password);  
  public void delUser(String id);  
}  

package com.fy.spring.proxy;  
  public class UserManagerImpl implements UserManager {  
  
  public void addUser(String id, String password) {  
    System.out.println(".: 掉用了UserManagerImpl.addUser()方法！ ");  
  
  }  
  
  public void delUser(String id) {  
    System.out.println(".: 掉用了UserManagerImpl.delUser()方法！ ");  
  
  }  
}  

package com.fy.spring.proxy;  
import java.lang.reflect.InvocationHandler;  
import java.lang.reflect.Method;  
import java.lang.reflect.Proxy;  
/**  
 *  
 * JDK动态代理类  
 *  
 *  
 */ 
public class JDKProxy implements InvocationHandler {  
  
  private Object targetObject;//需要代理的目标对象  
  
  public Object newProxy(Object targetObject) {//将目标对象传入进行代理  
    this.targetObject = targetObject;   
    return Proxy.newProxyInstance(targetObject.getClass().getClassLoader(),  
        targetObject.getClass().getInterfaces(), this);//返回代理对象  
  }  
  
  public Object invoke(Object proxy, Method method, Object[] args)//invoke方法  
      throws Throwable {  
    checkPopedom();//一般我们进行逻辑处理的函数比如这个地方是模拟检查权限  
    Object ret = null;   // 设置方法的返回值  
    ret = method.invoke(targetObject, args);    //调用invoke方法，ret存储该方法的返回值  
    return ret;  
  }  
  
  private void checkPopedom() {//模拟检查权限的例子  
    System.out.println(".:检查权限 checkPopedom()!");  
  }  
}  

package com.fy.spring.proxy;    
import java.lang.reflect.Method;  
  
import net.sf.cglib.proxy.Enhancer;  
import net.sf.cglib.proxy.MethodInterceptor;  
import net.sf.cglib.proxy.MethodProxy;  
  
/**  
 * CGLibProxy动态代理类的实例  
 *   
 *  
 */ public class CGLibProxy implements MethodInterceptor {  
  
  private Object targetObject;// CGLib需要代理的目标对象  
  
  public Object createProxyObject(Object obj) {  
    this.targetObject = obj;  
    Enhancer enhancer = new Enhancer();  
    enhancer.setSuperclass(obj.getClass());  
    enhancer.setCallback(this);  
    Object proxyObj = enhancer.create();  
    return proxyObj;// 返回代理对象  
  }  
  
  public Object intercept(Object proxy, Method method, Object[] args,  
      MethodProxy methodProxy) throws Throwable {  
    Object obj = null;  
    if ("addUser".equals(method.getName())) {// 过滤方法  
      checkPopedom();// 检查权限  
    }  
    obj = method.invoke(targetObject, args);  
    return obj;  
  }  
  
  private void checkPopedom() {  
    System.out.println(".:检查权限 checkPopedom()!");  
  }  
}  

public class Client {  
  
  public static void main(String[] args) {  
  
    UserManager userManager = (UserManager) new CGLibProxy()  
        .createProxyObject(new UserManagerImpl());  
    System.out.println("-----------CGLibProxy-------------");  
    userManager.addUser("tom", "root");  
    System.out.println("-----------JDKProxy-------------");  
    JDKProxy jdkPrpxy = new JDKProxy();  
    UserManager userManagerJDK = (UserManager) jdkPrpxy  
        .newProxy(new UserManagerImpl());  
    userManagerJDK.addUser("tom", "root");  
  }  
  
}