Spring单例Bean中注入多例Bean

灰太狼 2021-03-30 16:19 791阅读 0赞

**问题:**

当在一个单例Bean中注入一个多例Bean的时候,是获取不到那个多例对象的,因为,单例在初始化的时候,就直接初始化,这个多例Bean啦, 一直获取的是第一次初始化的Bean

配置文件:

````
<?xml version=”1.0” encoding=”UTF-8”?>
<beans xmlns=”http://www.springframework.org/schema/beans“
    xmlns:xsi=”http://www.w3.org/2001/XMLSchema-instance“
    xmlns:aop=”http://www.springframework.org/schema/aop“
    xsi:schemaLocation=”http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd"&gt;
        
        <bean id=”single” class=”com.lzd.spring.context.resource.test.bean.SingletonObject”>
            <property name=”prototypeObject” ref=”prototype”></property>
        </bean>
        
        <bean id=”prototype” class=”com.lzd.spring.context.resource.test.bean.PrototypeObject” scope=”prototype”>
            <property name=”name” value=”刘东”></property>
            <property name=”password” value=”123”></property>
            <!— <aop:scoped-proxy/> —>
        </bean>
````

SingletonObject对象:

````
package com.lzd.spring.context.resource.test.bean;

public class SingletonObject {

private PrototypeObject prototype;

public void setPrototypeObject(PrototypeObject prototype){
        this.prototype = prototype;
    }
    
    public PrototypeObject getPrototype(){
        return this.prototype;
    }
    
}
````

PrototypeObject对象:

````
package com.lzd.spring.context.resource.test.bean;
/*
 
  <P>Description: 这是一个多例的对象</P>
  @ClassName: PrototypeObject
  @author lzd  2017年2月15日 上午10:54:52
 /
public class PrototypeObject {

private String name;
    private String password;
    
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
}
````

ApplicationResourceTest测试类:

````
package com.lzd.spring.context.resource.test;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.lzd.spring.context.resource.test.bean.SingletonObject;

public class ApplicationResourceTest {

@Test
    public void applicationResource(){
        ApplicationContext context = new ClassPathXmlApplicationContext(new String[]{“classpath:application.xml”});
        
        
        SingletonObject s = (SingletonObject) context.getBean(“single”);
        
        for (int i = 0; i < 10; i++)
        System.out.println(s.getPrototype());
        
    }
    
}
````

![wKiom1ijypGAyh57AAIS3UbJ9ZM796.png][]

**问题解决:**

配置文件:

<!— 添加下面,一行,每次创建的,都是一个代理对象,然后注入获取的都是新的对象 —>
            <aop:scoped-proxy/>
        </bean>
````

测试结果:

![wKiom1ijy\_TxHrPNAAG0x6YhEuw734.png][wKiom1ijy_TxHrPNAAG0x6YhEuw734.png]

[wKiom1ijypGAyh57AAIS3UbJ9ZM796.png]: /images/20210331/1617121161691.png
[wKiom1ijy_TxHrPNAAG0x6YhEuw734.png]: /images/20210331/1617121143326.png