// patterns/ProxyDemo.java

// (c)2021 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.

// Basic demonstration of the Proxy pattern.

interface ProxyBase {

void f();

void g();

void h();

}

class Proxy implements ProxyBase {

private ProxyBase 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 {

@Override public void f() {

System.out.println("Implementation.f()");

}

@Override public void g() {

System.out.println("Implementation.g()");

}

@Override 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()

*/