如何使用Proxy模式及Java内建的动态代理机制

1.Proxy
模式
代理模式支持将某些操作从实际的对象中分离出来，通过它的代理类提供处理。这样便于修改和管理这些特定的操作。
下面示例一个代理模式的实现。
<<interface>>Subject.java
package
com.zj.proxy;
 
public

interface
Subject {
   
void
operation1();
   
   
void
operation2(String arg);
}
现实类
RealSubject.java
package
com.zj.proxy;
 
public

class
RealSubject
implements
Subject {
 
   
public

void
operation1() {
      
System.
out
.println(
"Realer do operation1"
);
   
}
 
   
public

void
operation2(String arg) {
      
System.
out
.println(
"Realer do operation2 with "
+ arg);
   
}
}
代理类
ProxySubject.java
package
com.zj.proxy;
 
public

class
ProxySubject
implements
Subject {
   
private
Subject
proxied
;
//
被代理对象
 
   
public
ProxySubject(Subject
proxied) {
      
this
.
proxied
= proxied;
   
}
 
   
public

void
operation1() {
      
System.
out
.println(
"Proxyer do operation1"
);
      
proxied
.operation1();
   
}
 
   
public

void
operation2(String arg) {
      
System.
out
.println(
"Proxyer do operation2 with "
+ arg);
      
proxied
.operation2(arg);
   
}
}
测试类
SimpleProxyDemo.java
package
com.zj.proxy.client;
 
import
com.zj.proxy.Subject;
import
com.zj.proxy.RealSubject;
import
com.zj.proxy.ProxySubject;
 
public

class
SimpleProx