Spring4 In Action-3.2@Scope单例多例Bean

Posted 2020-10-05 第二天半

Spring In [email protected]单例、多例Bean

代码下载地址：http://download.csdn.net/download/poiuy1991719/9967494

 

Singleton:单例    
@Scope(ConfigurableBeanFactory.SCOPE_SINGLETON)
@Scope("singleton")

 

Prototype：每次注入都会创建新的  
@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
@Scope("prototype") 

 

 

Session:Web的每一次会话    

 Request:Web的每一次请求

package com.bean.conditional;

import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Component;

@Component("magicBeanName")//重命名：配置类里面的方法与之对应
public class MagicBean {
    private String name="MagicBean";
    public MagicBean() {
        System.out.println("MagicBean:实例化"+this);
    }
    
    public void showName(){
        System.out.println("Show Name is:"+name);
    }
}

 

package com.bean.conditional;

import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Scope;

@Configuration
@ComponentScan(basePackages={"com.bean"})
public class BeanConfigs {

    @Bean
    //Singleton:单例  Prototype：每次注入都会创建新的 Session:Web的每一次会话  Request:Web的每一次请求
//    @Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
    @Scope("prototype")
    //@Scope(ConfigurableBeanFactory.SCOPE_SINGLETON)
//    @Scope("singleton")
    public MagicBean magicBeanName(){//方法名来源，Bean类的注解：@Component("magicBeanName")
        return new MagicBean();
    }
}

 

package test;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.bean.conditional.BeanConfigs;
import com.bean.conditional.MagicBean;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes={BeanConfigs.class})
public class test {
    @Autowired
    MagicBean mb;
    
    @Autowired
    MagicBean mb1;

    @Test
    public void selfTest(){
        mb.showName();
        mb1.showName();
    }
}

 

 

也可以通过xml文件配置来实现：

<bean id="magicBean" scope="prototype"></bean>