设计模式-享元模式

public class Engine {
    private String name;
    private String molde;

    public Engine(String name, String molde) {
        System.out.println("开始造发动机:"+name);
        this.name = name;
        this.molde = molde;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getMolde() {
        return molde;
    }

    public void setMolde(String molde) {
        this.molde = molde;
    }

    @Override
    public String toString() {
        return "Engine{" +
                "name=‘" + name + ‘\‘‘ +
                ", molde=‘" + molde + ‘\‘‘ +
                ‘}‘;
    }
}

//工厂类
public class EngineFactory {
    Map<String,Engine> engineMap=new HashMap<String,Engine>();
    public Engine getEngine(String name,String molde){
        if(null!=engineMap.get(name)){
            return engineMap.get(name);
        }
        Engine engine=new Engine(name,molde);
        engineMap.put(name,engine);
        return engine;
    }
}
//外部变化部分
public class Car {
    private String type;
    private Engine engine;


    public Car(String type, Engine engine) {
        this.type = type;
        this.engine = engine;
    }

    public String getType() {
        return type;
    }

    public void setType(String type) {
        this.type = type;
    }

    public Engine getEngine() {
        return engine;
    }

    public void setEngine(Engine engine) {
        this.engine = engine;
    }

    @Override
    public String toString() {
        return "Car{" +
                "type=‘" + type + ‘\‘‘ +
                ", engine=" + engine +
                ‘}‘;
    }
}
//测试类
public class Test {
    public static void main(String[] args) {
        EngineFactory engineFactory=new EngineFactory();
        Car car1=new Car("高级car",engineFactory.getEngine("高级发动机","001"));
        Car car2=new Car("高级car",engineFactory.getEngine("高级发动机","001"));

        Car car3=new Car("低级car",engineFactory.getEngine("一般发动机","001"));
        Car car4=new Car("低级car",engineFactory.getEngine("一般发动机","001"));

        System.out.println(car1+"/r"+car2+"/r"+car3+"/r"+car4);

    }
}