状态模式应用1（去掉过多的if...else)

状态接口类

package com.fczfr.pattern.behavior.state.sample1;

public interface State {
	// 状态0 
	public final static int STATUS_0 = 0;  
	// 状态1 
	public final static int STATUS_1 = 1; 
	
	public void sampleOperation();
	
	public int getStatus();
}

状态0实现类

package com.fczfr.pattern.behavior.state.sample1;

public class State0 implements State {

	public void sampleOperation() {
		System.out.println("当前状态为状态0");
	}

	public int getStatus() {
		return this.STATUS_0;
	}
	
	
}

状态1实现类

package com.fczfr.pattern.behavior.state.sample1;

public class State1 implements State {

	public void sampleOperation() {
		System.out.println("当前状态为状态1");
	}

	public int getStatus() {
		return this.STATUS_1;
	}
}

状态工厂类：

package com.fczfr.pattern.behavior.state.sample1;

import java.util.ArrayList;
import java.util.List;

public class StateFactory {
	List<State> stateList = null;
	public StateFactory(){
		stateList = new ArrayList<State>();
		stateList.add(new State0());
		stateList.add(new State1());
	}
	
	public State getState(int status){
		for(State state:stateList){
			if(state.getStatus()==status){
				return state;
			}
		}
		return null;
	}
}

最后，编写客户端测试类

package com.fczfr.pattern.behavior.state.sample1;

public class Client {

	public static void main(String[] args) {
		StateFactory factory = new StateFactory();
		factory.getState(State.STATUS_1).sampleOperation();
	}

}

运行结果：

当前状态为状态1


该模式，只要传递一个静态的状态，就可以执行该需要状态的执行类。