状态模式

  状态模式把状态的改变和对应状态下的操作放到了一起,

package com.roc.state;

public class Context {

    private State state;
    
    public Context(State state){
        this.state=state;
    }

    public State getState() {
        return state;
    }

    public void setState(State state) {
        this.state = state;
    }
    
    public void stateChange(){
        state.action(this);
    }
    
}

package com.roc.state;
/**
 * 抽象状态类
 * @author liaowp
 *
 */
public abstract class State {
    public abstract void action(Context context);
}

//具体的类,执行相应操作,并设置操作后的状态

package com.roc.state;

public class OpenSate extends State{

    public void action(Context context) {
        System.out.println("开");
        context.setState(new CloseState());
    }

}