package com.ietree.basicskill.designpattern.dynamicproxy.jdk;

/**
 * 接口类
 * 
 * @author Root
 */
public interface ISomeService {
  
  String doFirst();
  
  void doSecond();
}

package com.ietree.basicskill.designpattern.dynamicproxy.jdk;

/**
 * 实现类
 * 
 * @author Root
 */
public class SomeServiceImpl implements ISomeService {

  @Override
  public String doFirst() {
    System.out.println("执行doFirst()...");
    String result = "abcde";
    return result;
  }

  @Override
  public void doSecond() {
    System.out.println("执行doSecond()...");
  }

}

package com.ietree.basicskill.designpattern.dynamicproxy.jdk;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

public class Main {
  public static void main(String[] args) {

    final ISomeService target = new SomeServiceImpl();
    
    // 使用JDK的Proxy动态代理，要求目标类和代理类必须实现相同的接口，因为其底层的执行原理与静态代理的相同
    ISomeService service = (ISomeService) Proxy.newProxyInstance(
        // 目标类的类加载器
        target.getClass().getClassLoader(),
        // 目标类所实现的所有接口
        target.getClass().getInterfaces(), 
        new InvocationHandler() {
          // proxy：代理对象
          // method：目标方法
          // args：目标方法的参数列表
          @Override
          public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
            // 调用目标方法
            Object result = method.invoke(target, args);
            if (result != null) {
              result = ((String) result).toUpperCase();
            }
            return result;
          }
        });
    String result = service.doFirst();
    System.out.println(result);

    service.doSecond();
  }
}

package com.ietree.basicskill.designpattern.dynamicproxy.cglib;

/**
 * 实现类
 * 
 * @author Root
 */
public class SomeService {

  public String doFirst() {
    System.out.println("执行doFirst()...");
    String result = "abcde";
    return result;
  }

  public void doSecond() {
    System.out.println("执行doSecond()...");
  }

}

package com.ietree.basicskill.designpattern.dynamicproxy.cglib;

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 MyCglibFactory implements MethodInterceptor {

  private SomeService target;
  
  public MyCglibFactory() {
    super();
    target = new SomeService();
  }

  public SomeService myCglibCreator() {
    // 创建增强器对象
    Enhancer enhancer = new Enhancer();
    // 指定目标类，即父类
    enhancer.setSuperclass(SomeService.class);
    // 设置回调接口对象
    enhancer.setCallback(this);

    return (SomeService) enhancer.create();
  }

  @Override
  public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
    // 调用目标方法
    Object result = method.invoke(target, args);
    if (result != null) {
      result = ((String) result).toUpperCase();
    }
    return result;
  }

}

package com.ietree.basicskill.designpattern.dynamicproxy.cglib;

public class Main {
  public static void main(String[] args) {

    SomeService service = new MyCglibFactory().myCglibCreator();
    
    String result = service.doFirst();
    System.out.println("result = " + result);

    service.doSecond();
  }
}

执行doFirst()...
result = ABCDE
执行doSecond()...