package proxy_pattern;
public interface Subject {
public abstract void Request();
}
package proxy_pattern;
public class RealSubject implements Subject {
@Override
public void Request() {
System.out.println("This is the realRequest!");
}
}
package proxy_pattern;
public class Proxy implements Subject {
RealSubject realSubject;
@Override
public void Request() {
if (realSubject == null) {
realSubject = new RealSubject();
}
realSubject.Request();
}
}
package proxy_pattern;
public class Main {
public static void main(String args[]) {
Proxy proxy = new Proxy();
proxy.Request();
}
}
/***
* The proxy_pattern uses composite to invoke the real request indirectly.
* In some degree,this way can be seen as a hide for the original object.
* The proxy_class and original_class implement the same interface so as to
* complete the action without the trace.
* There are some application about the proxy_pattern:
* The first is kind of Remote_Proxy,which means the proxy_object can represent
* "a part" or "the whole" of the original_object with different address.
* The second is Virtual_Proxy that create "huge" object temporarily,which can
* storage the "expensive" object in the aspect of initialization.Such as:Delayed page loading.
* The third is Security_Proxy,which is used to control the original object's access authority.
* The last is Intelligent_Guidance that processes the additional internal affairs.
*/
This is a general introduction to the 23 design patterns：
https://blog.csdn.net/GZHarryAnonymous/article/details/81567214