spring之通过FactoryBean配置Bean

Posted 2020-11-24 西西嘛呦

Car.java

package com.gong.spring.beans.factoryBean;

public class Car {
    private String name;
    private double price;
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public double getPrice() {
        return price;
    }
    public void setPrice(double price) {
        this.price = price;
    }
    public Car(String name, double price) {
        super();
        this.name = name;
        this.price = price;
    }
    @Override
    public String toString() {
        return "Car [name=" + name + ", price=" + price + "]";
    }
    
}

CarFactoryBean.java

package com.gong.spring.beans.factoryBean;

import org.springframework.beans.factory.FactoryBean;

public class CarFactoryBean implements FactoryBean<Car> {
    
    private String name;
    public void setName(String name) {
        this.name = name;
    }
    //返回Bean的对象
    @Override
    public Car getObject() throws Exception {
        // TODO Auto-generated method stub
        return new Car(name,200000);
    }
    //返回bean的类型
    @Override
    public Class<?> getObjectType() {
        // TODO Auto-generated method stub
        return Car.class;
    }
    //是否是单例
    @Override
    public boolean isSingleton() {
        // TODO Auto-generated method stub
        return true;
    }

}

beans-factoryBean.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="car" class="com.gong.spring.beans.factoryBean.CarFactoryBean">
        <property name="name" value="baoma"></property>
    </bean>
</beans>

Main.java

package com.gong.spring.beans.factoryBean;

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Main {
    public static void main(String[] args) {
        //1.创建spring的IOC容器对象
        ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext("beans-factoryBean.xml");
        //2.从容器中获取Bean实例
        Car car = (Car) ctx.getBean("car");
        System.out.println(car.toString());
        ctx.close();
    }
}

输出：