// patterns/ProxyDemo.java
// (c)2017 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
// Simple demonstration of the Proxy pattern

interface ProxyBase {
 void f();
 void g();
 void h();
}

class Proxy implements ProxyBase {
 private ProxyBase implementation;
 Proxy() {
 implementation = new Implementation();
 }
 // Pass method calls to the implementation:
 @Override
 public void f() { implementation.f(); }
 @Override
 public void g() { implementation.g(); }
 @Override
 public void h() { implementation.h(); }
}

class Implementation implements ProxyBase {
 public void f() {
 System.out.println("Implementation.f()");
 }
 public void g() {
 System.out.println("Implementation.g()");
 }
 public void h() {
 System.out.println("Implementation.h()");
 }
}

public class ProxyDemo {
 public static void main(String[] args) {
 Proxy p = new Proxy();
 p.f();
 p.g();
 p.h();
 }
}
/* Output:
Implementation.f()
Implementation.g()
Implementation.h()
*/