Java-马士兵设计模式学习笔记-命令模式

一、概述

命令模式

二、代码

1.Client.java

 public class Client {

     public void request(Server server){
         server.addCommand(new TextCommand());
         server.addCommand(new ImageCommand());
         server.doSomething();
     }
 }

2.Server.java

 public class Server {

     private List<Command> commands = new ArrayList<Command>();

     public void doSomething() {
         for(Command c : commands){
             c.execute();
         }
     }

     public void addCommand(Command command) {
         commands.add(command);
     }

 }

3.Command.java

 public abstract class Command {

     public abstract void execute();
     public abstract void unDo();

 }

4.TextCommand.java

 public class TextCommand extends Command {

     @Override
     public void execute() {
         System.out.println("TextCommand...........");
     }

     @Override
     public void unDo() {
         // 涉及到操作的历史记录
     }

 }

5.ImageCommand.java

 public class ImageCommand extends Command {

     @Override
     public void execute() {
         System.out.println("ImageCommand...........");
     }

     @Override
     public void unDo() {
         // 涉及到操作的历史记录
     }

 }

6.Test.java

 public class Test {

     @org.junit.Test
     public void test(){
         Client c = new Client();
         c.request(new Server());
     }

 }

三、运行结果