關於spring”通配符的匹配很全面, 但無法找到元素 'context:component-scan' 的聲明“的錯誤

關於spring配置的問題

近日學習spring時遇到了這個問題：

org.springframework.beans.factory.xml.XmlBeanDefinitionStoreException: Line 12 in XML document from URL [file:/F:/workspace/spring/target/classes/applicationContext.xml] is invalid; nested exception is org.xml.sax.SAXParseException; lineNumber: 12; columnNumber: 55; cvc-complex-type.2.4.c: 通配符的匹配很全面, 但無法找到元素 'context:component-scan' 的聲明。

報錯如下：

17:21:22,400 ERROR main context.ContextLoader:331 - Context initialization failed
org.springframework.beans.factory.xml.XmlBeanDefinitionStoreException: Line 14 in XML document from URL [file:/F:/workspace/spring/target/classes/applicationContext.xml] is invalid; nested exception is org.xml.sax.SAXParseException; lineNumber: 14; columnNumber: 54; cvc-complex-type.2.4.c: 通配符的匹配很全面, 但無法找到元素 'context:component-scan' 的聲明。
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:399)
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:336)
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:304)
	at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:181)
	at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:217)
	at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:188)
	at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:125)
	at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:94)
	at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:129)
	at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:537)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:452)
	at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403)
	at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306)
	at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106)
	at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4135)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4630)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:785)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:445)
	at org.apache.catalina.startup.Embedded.start(Embedded.java:825)
	at org.codehaus.mojo.tomcat.AbstractRunMojo.startContainer(AbstractRunMojo.java:558)
	at org.codehaus.mojo.tomcat.AbstractRunMojo.execute(AbstractRunMojo.java:255)
	at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:133)
	at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208)
	at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
	at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
	at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:108)
	at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:76)
	at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
	at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:116)
	at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:361)
	at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:155)
	at org.apache.maven.cli.MavenCli.execute(MavenCli.java:584)
	at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:213)
	at org.apache.maven.cli.MavenCli.main(MavenCli.java:157)
	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:483)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
	at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
	at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)

查了好多資料，發現是applicationContext.xml文件有點小問題。

報錯時的文件頭：

<?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:tx="http://www.springframework.org/schema/tx" 
    xmlns:aop="http://www.springframework.org/schema/aop"
	xmlns:context="http://www.springframework.org/schema/context" 
	xmlns:jee="http://www.springframework.org/schema/jee"
    xsi:schemaLocation="
    	http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd">

添加了一些schemaLocation：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    <span style="white-space:pre">	</span>xmlns:context="http://www.springframework.org/schema/context"
    <span style="white-space:pre">	</span>xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    <span style="white-space:pre">	</span>xmlns:aop="http://www.springframework.org/schema/aop"
    <span style="white-space:pre">	</span>xmlns:mvc="http://www.springframework.org/schema/mvc"
    <span style="white-space:pre">	</span>xmlns:jee="http://www.springframework.org/schema/jee"
    <span style="white-space:pre">	</span>xmlns:tx="http://www.springframework.org/schema/tx"
    <span style="white-space:pre">	</span>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
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
        http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">

就OK了~(*^__^*) ，注:不要拷貝上面配置，要根據自己項目缺少的schema而添加

原因：

我這個原因是有些“schemaLocation”沒有寫。把對應的加上就可以了。

其根本原因是spring啓動是時候要通過相應的xsd文件來檢驗xml文件，找不到相應的xsd文件的時候就會報錯。

那麼spring是如何加載xsd文件的呢？

spring是默認從本地加載xsd文件的，舉個栗子：我們打開spring-context的jar包，找到spring.schemas這個文件

然後在org/springframework/context/config目錄下可以找到這些xsd文件。默認加載的就是這些文件。

spring這一點細節做得比較好，把所有版本的xsd文件都放進來了，無論在spring配置文件中寫哪個版本的schemaLocation，都能找得到。如果不寫schemaLocation的版本號是，默認是當前版本。

解決辦法：

檢查spring配置文件裏有沒有配相應的schema配置，補充上就可以了