之前学习Spring的时候一直用的Myeclipse和eclipse编辑器，将配置文件直接放进当前Project下进行加载解析就行了。但是换成IEDA以后出现了一些问题。重温Spring知识点的时候，我加入相应的依赖之后，编辑类App1_get_ioc，进行单元测试后，输出错误为：
十一月 15,2017 6:35:09 下午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh 信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@606d8acf: startup date [Wed Nov 15 18:35:09 CST 2017]; root of context hierarchy 十一月 15,2017 6:35:09 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions 信息: Loading XML bean definitions from class path resource [com/zj/spring01/helloworld/applicationContext.xml] org.springframework.beans.factory.BeanDefinitionStoreException: IOException parsing XML document from class path resource [com/zj/spring01/helloworld/applicationContext.xml]; nested exception is java.io.FileNotFoundException: class path resource [com/zj/spring01/helloworld/applicationContext.xml] cannot be opened because it does not exist at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:341) at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:302) at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:174) at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:209) at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:180) at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:243) at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:127) at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:93) at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshbeanfactory(AbstractRefreshableApplicationContext.java:130) at org.springframework.context.support.AbstractApplicationContext.obtainFreshbeanfactory(AbstractApplicationContext.java:537) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:451) at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139) at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83) at com.zj.spring01.helloworld.App1_get_ioc.testIOC(App1_get_ioc.java:22) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:497) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20) at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28) at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:44) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:180) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:41) at org.junit.runners.ParentRunner$1.evaluate(ParentRunner.java:173) at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28) at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31) at org.junit.runners.ParentRunner.run(ParentRunner.java:220) at org.junit.runner.JUnitCore.run(JUnitCore.java:159) at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68) at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47) at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242) at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70) Caused by: java.io.FileNotFoundException: class path resource [com/zj/spring01/helloworld/applicationContext.xml] cannot be opened because it does not exist at org.springframework.core.io.ClassPathResource.getInputStream(ClassPathResource.java:157) at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:328) ... 36 moreApp1_get_ioc.java
package com.aj.spring01.helloworld;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class App1_get_ioc {
//1.通过工厂类得到IOC容器创建的对象
@Test
public void testIOC() throws Exception{
//创建对象
//现在把创建对象交给spring容器
ApplicationContext ac = new ClassPathXmlApplicationContext
("com/aj/spring01/helloworld/applicationContext.xml");
User user=(User)ac.getBean("user");
user.setId(100);
user.setName("good boy!");
System.out.println(user);
System.out.println(user.getId());
System.out.println(user.getName());
}
}
applicationContext.xml
<?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:p="http://www.springframework.org/schema/p"
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.xsd">
<!-- IOC容器的配置： 要创建的所有的对象都配置在这里
<bean id="user" class="cn.itcast.a_hello.User" init-method="init_user" destroy-method="destroy_user" scope="singleton" lazy-init="false"></bean>
-->
<bean id="user" class="com.aj.spring01.helloworld.User" init-method="init_user" destroy-method="destroy_user" scope="singleton" lazy-init="false"></bean>
<bean id="user1" class="com.aj.spring01.helloworld.User"></bean>
</beans>
异常说明的也比较清楚，就是指定的路径不存在！我也很好奇，之前在eclipse上运行完全没问题，可是到了IDEA上运行就出现问题了。于是查询了关于ClassPathXmlApplicationdContext的一些用法，
ClassPathXmlApplicationContext[只能读放在web-info/classes目录下的配置文件]。ClassPathXmlApplicationContext 默认从类路径加载配置文件，在类路径文件夹下。这里用的maven的文件夹结构，如下图：
target文件夹就是存放class类的文件夹相应目录下，可是其下面并没有applicationContext.xml文件。IDEA在源码目录（src/main/java），只会把.java文件编译成.class文件，存到classes文件夹下，其他的配置文件是不会做处理的（MyEclipse会把配置文件复制到相应的包下）。但可以在resources文件夹下，创建相应的包目录，放到相应的目录下，IDEA就会将配置文件，复制到classes文件夹下，也就可以访问到了。 在这里只需将applicationContext.xml复制到target目录下的helloworld下即可，然后再次Junit编译,结果如下：
