简单工厂模式

工厂模式

简单例子Demo

1. 创建一个 接口类Animals.java

   public interface Animals {
    void cry();
   }
   

2. 创建Dog、Cat、Bird等类实现Animals接口

   Dog.java

   public class Dog implements Animals {
    @Override
    public void cry() {
        System.out.println("Dog cry()");
    } 
   }
   

   Cat.java

   public class Cat implements Animals {
    @Override
    public void cry() {
        System.out.println("Cat cry()");
    }
   }
   

   Bird.java

   public class Bird implements Animals {
    @Override
    public void cry() {
        System.out.println("Bird cry()");
    }
   }
   

3. 创建动物工厂类 AnimalFactory.java

   public class AnimalFactory {
    public Animals getAnimals(String animalType) {
        if (animalType == null) {
            return null;
        }
        if (animalType.equalsIgnoreCase("dog")) {
            return new Dog();
        }else if (animalType.equalsIgnoreCase("cat")) {
            return new Cat();
        }else if (animalType.equalsIgnoreCase("bird")) {
            return new Bird();
        }
        return null;
    }
   }
   

4. 测试Demo

   public class Demo {
    public static void main(String[] args) {
        AnimalFactory animalFactory = new AnimalFactory();
        
        Animals animals1 = animalFactory.getAnimals("dog");
        animals1.cry();
        
        Animals animals2 = animalFactory.getAnimals("cat");
        animals2.cry();
        
        Animals animals3 = animalFactory.getAnimals("bird");
        animals3.cry();
    }
   }