混合配置
还存留一个很重要的问题：如果根配置是xml配置，在测试的时候如果用@Autowired自动注入，对象是null,用getbean()方法就可以拿到，有可能是 不是同一个上下文，这就不明白了，先存疑吧。？？？？？
看Spring实战(第4版)笔记
在实际的程序中，可能会有 自动配置，JavaConfig配置 和XML 配置一起使用的情况。
那最好 建一个根配置，(JavaConfig配置类或者XML配置文件)，在根配置中加载所有的 JavaConfig配置类 和 xml配置文件，并且启用组件扫描(自动配置)，让Spring同时加载 基于Java的配置 基于xml的配置 和自动配置
比如 我有一个自动扫描的类 两个配置类 两个XML配置文件
MyCompactDis类采用自动扫描配置
CompactDis类 配置在了CDConfig配置类中 , CDPlayer类 配置在了CDPlayerConfig配置类中，
BlankCompactDisc配置在了类路径下的bean-config.xml配置文件中 BlankCompactDisc配置在了类路径下的bean-config-1.xml配置文件中
根配置是JavaConfig类 ---@ComponentScan注解 @Import注解 @ImportRes注ource解
定义根配置类 @ComponentScan注解启用 自动扫描 并且 @Import 注解 引入 CDConfig配置类 和 CDPlayerConfig配置类，@ImportResource引入bean-config.xml配置文件。
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.context.annotation.ImportResource;
@Configuration
@ComponentScan
@Import({ CDPlayerConfig.class, CDConfig.class })
@ImportResource({"classpath:bean-config.xml","classpath:bean-config-1.xml"})
public class SystemConfig {
}
测试
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;
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = SystemConfig.class)
public class CDPlayerTest {
@Autowired
private MyCompactDisc myCompactDisc;
@Autowired
private CompactDisc compactDisc;
@Autowired
private CDPlayer cdPlayer;
@Autowired
private BlankCompactDisc blankCompactDisc;
@Autowired
private NoBlankCompactDisc noBlankCompactDisc;
@Test
public void test() {
myCompactDisc.play();
compactDisc.play();
cdPlayer.play();
blankCompactDisc.play();
noBlankCompactDisc.play();
}
}
根配置是XML配置----<context:component-scan>元素 <bean>元素 <import />元素
使用<context:component-scan>元素开始自动包扫描，使用<bean>元素引入 JavaConfig配置类，使用<import />元素引入其他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"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd">
<!--开启自动扫描-->
<context:component-scan base-package="com.demo.SpringBeanDemo"/>
<!--引入其它JavaConfig配置类 class属性指定配置类-->
<bean class="com.demo.SpringBeanDemo.CDConfig"></bean>
<bean class="com.demo.SpringBeanDemo.CDPlayerConfig"></bean>
<!--加载其他xml配置文件 resource属性指定在类路径下的配置文件 -->
<import resource="bean-config.xml"></import>
<import resource="bean-config-1.xml"></import>
</beans>
测试
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class CDPlayerTest2 {
static ApplicationContext applicationContext = new ClassPathXmlApplicationContext("system-config.xml");
private MyCompactDisc myCompactDisc = (MyCompactDisc) applicationContext.getBean("myCompactDisc");
private CompactDisc compactDisc = (CompactDisc) applicationContext.getBean("compactDisc");
private CDPlayer cdPlayer = (CDPlayer) applicationContext.getBean("cdPlayer");
private BlankCompactDisc blankCompactDisc = (BlankCompactDisc) applicationContext.getBean("blankCompactDisc");
private NoBlankCompactDisc noBlankCompactDisc = (NoBlankCompactDisc) applicationContext.getBean("noBlankCompactDisc");
@Test
public void test() {
myCompactDisc.play();
compactDisc.play();
cdPlayer.play();
blankCompactDisc.play();
noBlankCompactDisc.play();
}
}
以下附上 这5个类的具体的定义和配置
定义MyCompactDisc类 并使用自动配置
import org.springframework.stereotype.Component;
@Component
public class MyCompactDisc {
public void play() {
System.out.println("this is auto config playing hahah by dream_s");
}
}
定义CompactDisc类 并把它配置在CDConfig配置类中
public class CompactDisc {
private String artist = "dream_s";
private String music = "hahah";
public void play(){
System.out.println("playing "+music +" by "+artist);
}
}
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class CDConfig {
@Bean
public CompactDisc compactDisc(){
return new CompactDisc();
}
}
定义CDPlayer类 并把它配置在CDPlayerConfig配置类中
public class CDPlayer {
private CompactDisc compactDisc;
public CDPlayer(CompactDisc compactDisc) {
this.compactDisc = compactDisc;
}
public void play() {
compactDisc.play();
}
}
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class CDPlayerConfig {
@Bean
public CDPlayer cdPlayer(CompactDisc compactDisc){
return new CDPlayer(compactDisc);
}
}
定义BlankCompactDisc类 并配置在 根路径下 的 bean-config.xml文件中
public class BlankCompactDisc {
private String artist = "dream_s";
private String music = "hahah";
public void play() {
System.out.println("this is BlankCompactDisc playing " + music + "by " + artist);
}
}
<?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 = "blankCompactDisc" class = "com.demo.SpringBeanDemo.BlankCompactDisc"></bean>
</beans>
定义NoBlankCompactDisc类 并配置在 类路径下 的 bean-config-1.xml文件中
public class NoBlankCompactDisc {
public void play(){
System.out.println("this is xml config for NoBlankCompactDisc playing hahah by dream_s ");
}
}
<?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="noBlankCompactDisc" class="com.demo.SpringBeanDemo.NoBlankCompactDisc"></bean>
</beans>
