依赖注入

依赖注入是一种设计模式

实现方式

IAnimal.java

public  interface IAnimal{
    public String behavior();
    
}

Dog.java

public class Dog implements IAnimal{
    public Dog(){}

    @Override
    public String behavior(){
        return "= this is dog behavior=";
    }


}

Pig.java

public class Pig implements IAnimal{
    @Override
    public String behavior(){
        return "= this is pig behavior = ";
    }
}

CurrAnimal.java

public class CurrAnimal{
    private IAnimal animal = null;

    public CurrAnimal(IAnimal animal){
        this.animal = animal;
    }


    public void showBehavior(){
        String behavior = this.animal.behavior();
        System.out.println( behavior );
    }

    
}

Park.java

public  class Park{
    

    public CurrAnimal getCurrAnimal(){
        return new CurrAnimal(new Pig() );
    }

}

AnimalShow.java

public  class AnimalShow{
    public static void main(String[]  args){

        Park pk = new Park();

        CurrAnimal ca = pk.getCurrAnimal();
        ca.showBehavior();

    }
}

运行

= this is pig behavior =