Bean的实例化--静态工厂

1，创建实体类User

package com.songyan.demo1;

/**
 * 要创建的对象类
 * @author sy
 *
 */
public class User {
private String name;
private int age ;
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public int getAge() {
    return age;
}
public void setAge(int age) {
    this.age = age;
}

}

2，创建生产对象的工厂类

改工厂类必须有一个静态的返回值为“要生产的对象的类型”

package com.songyan.staticfactory;

import com.songyan.demo1.User;
/**
 * 创建User对象的工厂类
 * @author sy
 *
 */
public class UserFactory {
    /**
     * 该方法必须是static的
     * @return 工厂要创建的对像
     */
public static User createUser()
{
    return new User();
}
}

3，配置bean对象

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd ">
 3     
 4     <!--通过构造函数创建对象  -->
 5     <bean id="userid" class="com.songyan.demo1.User"></bean>
 6     
 7     <!--通过静态工厂创建对象  -->
 8     <!--通过 com.songyan.staticfactory.UserFactory类中的createUser方法创建名为user2的对象 -->
 9     <bean name="user2" class="com.songyan.staticfactory.UserFactory" factory-method="createUser"></bean>
10 </beans>

4，测试类

 1 package com.songyan.Test;
 2 
 3 import org.springframework.context.ApplicationContext;
 4 import org.springframework.context.support.ClassPathXmlApplicationContext;
 5 
 6 import com.songyan.demo1.User;
 7 
 8 public class Client {
 9 public static void main(String[] args) {
10     ApplicationContext applicationContext=new ClassPathXmlApplicationContext("applicationContext.xml");
11     /*User user=(User)applicationContext.getBean("userid");
12     System.out.println(user);*/
13     User user2=(User)applicationContext.getBean("user2");
14     System.out.println(user2);
15     
16 }
17 }

5，结果

来源：https://www.cnblogs.com/excellencesy/p/9103622.html

标签

bean

实例化

静态方法