Spring课程 Spring入门篇 3-3 Spring bean装配（上）之aware接口

课程链接：

本节主要介绍了以下内容：

1　　　　aware介绍

2　　　　代码演练

3　　　　课程总结

1　　　　aware介绍

1.1　　为什么要使用aware？

在java类中，可以方便的获取xml配置文件中的bean的各个属性。通过不同的aware可以获取不同的bean的属性

1.2　　有哪些类型的aware？

常见的有：

applicationContextAware（获取bean）

beanNameAware（获取beanname）

还有

beanFactoryAware等等

2　　　　代码演练

2.1　　applicationContextAware（验证aware获取的applicationContext 和测试获取的applicationContext 为同一个）

 实体类：

package com.imooc.aware;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;

public class MoocApplicationContext implements ApplicationContextAware{

    @Override
    public void setApplicationContext(ApplicationContext arg0)
            throws BeansException {
        System.out.println("MoocApplicationContext========》"+arg0.getBean("moocApplicationContext").hashCode());
    }

}

xml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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">

<bean id="moocApplicationContext" class="com.imooc.aware.MoocApplicationContext"></bean>
<!-- <bean id="moocBeanName" class="com.imooc.aware.MoocBeanName"></bean>  -->

</beans>

测试类：

package com.imooc.test.aware;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.BlockJUnit4ClassRunner;

import com.imooc.test.base.UnitTestBase;

@RunWith(BlockJUnit4ClassRunner.class)
public class TestAware extends UnitTestBase{

    public TestAware() {
        super("classpath:spring-aware.xml");
    }

    //测试ApplicationContext aware
    @Test
    public void testMoocApplicationContext(){
        System.out.println("testApplicationContext======》"+super.getbean("moocApplicationContext").hashCode());
    }

    //测试BeanNameAware
    /*@Test
    public void testMoocBeanName(){

    }*/
}

打印结果：

二月 27, 2019 6:37:13 下午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@5abce07: startup date [Wed Feb 27 18:37:13 CST 2019]; root of context hierarchy
二月 27, 2019 6:37:13 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [spring-aware.xml]
MoocApplicationContext========》282483842
testApplicationContext======》282483842
二月 27, 2019 6:37:13 下午 org.springframework.context.support.ClassPathXmlApplicationContext doClose
信息: Closing org.springframework.context.support.ClassPathXmlApplicationContext@5abce07: startup date [Wed Feb 27 18:37:13 CST 2019]; root of context hierarchy

2.2　　beanNameAware（获取xml配置中的beanname)

实体类：

package com.imooc.aware;

import org.springframework.beans.factory.BeanNameAware;

public class MoocBeanName implements BeanNameAware{

    @Override
    public void setBeanName(String arg0) {
        // TODO Auto-generated method stub
        System.out.println("beanName为"+arg0);
    }

}

xml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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">

<bean id="moocBeanName" class="com.imooc.aware.MoocBeanName"></bean> 

</beans>

测试类：

package com.imooc.test.aware;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.BlockJUnit4ClassRunner;

import com.imooc.test.base.UnitTestBase;

@RunWith(BlockJUnit4ClassRunner.class)
public class TestAware extends UnitTestBase{

    public TestAware() {
        super("classpath:spring-aware.xml");
    }

  //测试BeanNameAware
    @Test
    public void testMoocBeanName(){

    }
}

打印结果：

二月 27, 2019 7:17:55 上午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@2e9a6f43: startup date [Wed Feb 27 07:17:55 CST 2019]; root of context hierarchy
二月 27, 2019 7:17:55 上午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [spring-aware.xml]
beanName==moocBeanName
二月 27, 2019 7:17:56 上午 org.springframework.context.support.ClassPathXmlApplicationContext doClose
信息: Closing org.springframework.context.support.ClassPathXmlApplicationContext@2e9a6f43: startup date [Wed Feb 27 07:17:55 CST 2019]; root of context hierarchy

3　　　　课程总结

aware获取的bean和服务器调用的bean的内存地址完全一致。