Question

我想消除太多＆＃34; new＆＃34;在我的代码中创建。所以我决定使用构建器模式。如果可能的话，我也想利用Spring @Autowired。

public class Car
{
    @Autowired
    private Radio radio;

    @Autowired
    private Speaker speaker;

    @Autowired
    private Engine engine;

    private String model;

    public Car createCar()
    {
        radio.add(speaker);
        return this;
    }

    public static class Builder
    {
        private String model;

        public Builder(){}

        public Builder model(String model)
        {
            this.model = model;
            return this;
        }
    }
}

我想使用这样的东西。

Car car = new Car.Builder().model("A123").build();

这可能吗？

Answer 1

好的你可以使用类似于一些基本变化的东西首先使用默认的自动装配实例制作汽车和构建器，然后根据需要更改示例：

Car.calss

public class Car {
    private Radio radio;
    private Speaker speaker;
    private Engine engine;

    public Car(Radio radio, Speaker speaker, Engine engine) {
        this.radio = radio;
        this.speaker = speaker;
        this.engine = engine;
    }

    public Radio getRadio() {
        return radio;
    }

    public void setRadio(Radio radio) {
        this.radio = radio;
    }

    public Speaker getSpeaker() {
        return speaker;
    }

    public void setSpeaker(Speaker speaker) {
        this.speaker = speaker;
    }

    public Engine getEngine() {
        return engine;
    }

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

CarBuilder.class

@Component
public class CarBuilder {

    @Autowired
    private Radio radio;
    @Autowired
    private Speaker speaker;
    @Autowired
    private Engine engine;

    public CarBuilder setRadio(Radio radio) {
        this.radio = radio;
        return this;
    }

    public CarBuilder setSpeaker(Speaker speaker) {
        this.speaker = speaker;
        return this;
    }

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

    public Car createCar() {
        return new Car(radio, speaker, engine);
    }

}

并在代码中使用构建器，如下所示

@Component
public class CarMarket {

    @Autowired
    private CarBuilder carBuilder;

    private Car buildStandardCar(){
        return carBuilder.createCar();
    }


    private Car buildStandardCarButDifferentRadio(Radio radio){
        return carBuilder.setRadio(radio).createCar();
    }

}

我希望这会对你有所帮助:)。

Answer 2

我认为这应该有效：

@Component
    public class Car {
@Autowired
private Radio radio;
@Autowired
    private Speaker speaker;
@Autowired
    private Engine engine;  
private String model;
    }

然后是构建器类：

    @Component
    public class CarBuilder{
@Autowired
Car car;

public void addModel(String model){
this.car.setModel(model);
}

public Car getCar(){
return car;
}
}

然后是主课

 class Main{

public static void main(String args[]){
     Car car= context.getBean("carBuilder").addModel("abc").getCar();
}
}

如何使用Spring注释构建器模式

2 个答案: