[设计模式]Netd中的命令设计模式，NetworkManagementService中的监听者模式

 1 public interface Command {
 2     public void execute();
 3 }
 4 public class ConcreteCommand implements Command {
 5 
 6     private Receiver receiver = null;
 7     private String state;
 8 
 9     public ConcreteCommand(Receiver receiver){
10        this.receiver = receiver;
11     }  
12     public void execute() {
13        receiver.action();
14     }
15 }
16 
17 
18 public class Receiver {
19     public void action(){
20        //真正执行命令操作的功能代码
21     }
22 }
23 
24 public class Invoker {
25     private Command command = null;
26 
27     public void setCommand(Command command) {
28        this.command = command;
29     }
30 
31     public void runCommand() {
32        command.execute();
33     }
34 }
35 
36 public class Client {
37     public void assemble(){
38        //创建接收者
39        Receiver receiver = new Receiver();
40        //创建命令对象，设定它的接收者
41        Command command = new ConcreteCommand(receiver);
42        //创建Invoker，把命令对象设置进去
43        Invoker invoker = new Invoker();
44        invoker.setCommand(command);
45     }
46 }