策略模式

 将需要变化的那部分功能拿出来，

public interface RunBehavior {  跑抽象出一个接口
    void run();
}
public class RunNormally implements RunBehavior{ 正常跑
    @Override
    public void run() {
        System.out.println("harding running...");
    }
}
public class RunNoWay implements RunBehavior{ 不跑
    @Override
    public void run() {    
    }
}

public interface SayHiBehavior { 说 抽象出一个接口
    void sayHi();
}
public class SayHiNormally implements SayHiBehavior{ 正常说
    @Override
    public void sayHi() {
        System.out.println("gegege");
    }
}
public class SayHiScream implements SayHiBehavior{ 尖叫说
    @Override
    public void sayHi() {
        System.out.println("gagagagaga....");
    }
}

public abstract class Chicken {
    private SayHiBehavior sayHiBehavior;
    private RunBehavior runBehavior;
    
    public void setSayHiBehavior (SayHiBehavior sayHiBehavior) {
        this.sayHiBehavior=sayHiBehavior;
    }
    
    public void setRunBehavior(RunBehavior runBehavior){
        this.runBehavior=runBehavior;
    }
    
    public void performSayHi(){
        this.sayHiBehavior.sayHi();
    }
    
    public void performRun(){
        this.runBehavior.run();
    }
    
    public abstract void show();
}

public class WhiteChicken extends Chicken{
    @Override
    public void show() {
        System.out.println("white...");
    }
}

public class MyTest {
    public static void main(String[] args) {
        WhiteChicken whiteChicken=new WhiteChicken();
        whiteChicken.setRunBehavior(new RunNormally());
        whiteChicken.setSayHiBehavior(new SayHiNormally());
        
        whiteChicken.performSayHi();
        whiteChicken.performRun();
        whiteChicken.show();
    }
}

参考：

https://blog.csdn.net/zhangliangzi/article/details/52161211

https://blog.csdn.net/fiendvip/article/details/51113967