java中23种设计模式之11-命令模式（command pattern）

 

 

abstract class Command
{
public abstract void excute();
}

class AttackCommand extends Command
{
Soldier soldier=null;
public AttackCommand(Soldier soldier)
{
this.soldier=soldier;
}
public void excute()
{
soldier.attack();
}
}

class DefendCommand extends Command
{
Soldier soldier=null;
public DefendCommand(Soldier soldier)
{
this.soldier=soldier;
}
public void excute()
{
soldier.defend();
}
}

class Soldier
{
public void attack()
{
System.out.println("soldier attack");
}
public void defend()
{
System.out.println("soldier defend");
}
}

class Lord
{
Command command;
public void setCommand(Command command)
{
this.command=command;
}
public void start()
{
command.excute();
}
}

public class CommandPatternTest
{
public static void main(String[] args)
{
Soldier aSoldier=new Soldier();
Command aCommand=new AttackCommand(aSoldier);
Lord aLord=new Lord();
aLord.setCommand(aCommand);
aLord.start();

aCommand=new DefendCommand(aSoldier);
aLord.setCommand(aCommand);
aLord.start();
}
}

/////////////////////////////////////////

输出结果：

soldier attack
soldier defend