在Eclipse構建路徑庫和WEB-INF/lib文件夾中添加jar的差異

Question

我最近在Eclipse Helios IDE中部署基於Spring 3.0的Web應用程序時遇到了一個問題。我已經包含彈簧&它的依賴jar文件BuildPath - >庫 - >從我的本地存儲庫（maven本地庫）添加外部罐。當我試圖啓動服務器時，它拋出ClassNotFoundException，

注意：我可以在Eclipse Buildpath-Library中找到我的Spring-web jar。

SEVERE: Error configuring application listener of class org.springframework.web.context.ContextLoaderListener 
java.lang.ClassNotFoundException: org.springframework.web.context.ContextLoaderListener 
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1387) 
    at `enter code here`org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1233) 
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3786) 
    at org.apache.catalina.core.StandardContext.start(StandardContext.java:4342) 
    at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045) 
    at org.apache.catalina.core.StandardHost.start(StandardHost.java:719) 
    at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045) 
    at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443) 
    at org.apache.catalina.core.StandardService.start(StandardService.java:516) 
    at org.apache.catalina.core.StandardServer.start(StandardServer.java:710) 
    at org.apache.catalina.startup.Catalina.start(Catalina.java:578) 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
    at java.lang.reflect.Method.invoke(Unknown Source) 
    at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288) 
    at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413) 

.classpath文件：

<?xml version="1.0" encoding="UTF-8"?> 
<classpath> 
    <classpathentry kind="src" path="rest-client/src/main/java"/> 
    <classpathentry kind="src" path="rtsocketdatamonitor/src/main/java"/> 
    <classpathentry kind="src" path="rtsocketdatamonitor/src/main/resources"/> 
    <classpathentry kind="src" path="rest-client/src/main/resources"/> 
    <classpathentry kind="var" path="M2_REPO/commons-lang/commons-lang/2.2/commons-lang-2.2.jar" sourcepath="M2_REPO/commons-lang/commons-lang/2.2/commons-lang-2.2-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/log4j/log4j/1.2.14/log4j-1.2.14.jar" sourcepath="M2_REPO/log4j/log4j/1.2.14/log4j-1.2.14-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/slf4j/slf4j-api/1.6.2/slf4j-api-1.6.2.jar" sourcepath="M2_REPO/org/slf4j/slf4j-api/1.5.6/slf4j-api-1.5.6-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/commons-collections/commons-collections/3.1/commons-collections-3.1.jar" sourcepath="M2_REPO/commons-collections/commons-collections/3.1/commons-collections-3.1-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/dom4j/dom4j/1.6.1/dom4j-1.6.1.jar" sourcepath="M2_REPO/dom4j/dom4j/1.6.1/dom4j-1.6.1-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/hibernate/hibernate-commons-annotations/3.2.0.Final/hibernate-commons-annotations-3.2.0.Final.jar" sourcepath="M2_REPO/org/hibernate/hibernate-commons-annotations/3.2.0.Final/hibernate-commons-annotations-3.2.0.Final-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/hibernate/javax/persistence/hibernate-jpa-2.0-api/1.0.0.Final/hibernate-jpa-2.0-api-1.0.0.Final.jar" sourcepath="M2_REPO/org/hibernate/javax/persistence/hibernate-jpa-2.0-api/1.0.0.Final/hibernate-jpa-2.0-api-1.0.0.Final-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/javax/transaction/jta/1.1/jta-1.1.jar" sourcepath="M2_REPO/javax/transaction/jta/1.1/jta-1.1-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/hibernate/hibernate-entitymanager/3.6.0.Final/hibernate-entitymanager-3.6.0.Final.jar" sourcepath="M2_REPO/org/hibernate/hibernate-entitymanager/3.6.0.Final/hibernate-entitymanager-3.6.0.Final-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/cglib/cglib/2.2/cglib-2.2.jar" sourcepath="M2_REPO/cglib/cglib/2.2/cglib-2.2-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/javassist/javassist/3.12.0.GA/javassist-3.12.0.GA.jar" sourcepath="M2_REPO/javassist/javassist/3.12.0.GA/javassist-3.12.0.GA-sources.jar"/> 
    <classpathentry exported="true" kind="var" path="M2_REPO/org/slf4j/slf4j-log4j12/1.5.6/slf4j-log4j12-1.5.6.jar" sourcepath="M2_REPO/org/slf4j/slf4j-log4j12/1.5.6/slf4j-log4j12-1.5.6-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-aop/3.0.5.RELEASE/spring-aop-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-aop/3.0.5.RELEASE/spring-aop-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/aopalliance/aopalliance/1.0/aopalliance-1.0.jar" sourcepath="M2_REPO/aopalliance/aopalliance/1.0/aopalliance-1.0-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-asm/3.0.5.RELEASE/spring-asm-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-asm/3.0.5.RELEASE/spring-asm-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-beans/3.0.5.RELEASE/spring-beans-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-beans/3.0.5.RELEASE/spring-beans-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-core/3.0.5.RELEASE/spring-core-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-core/3.0.5.RELEASE/spring-core-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/commons-logging/commons-logging/1.1.1/commons-logging-1.1.1.jar" sourcepath="M2_REPO/commons-logging/commons-logging/1.1.1/commons-logging-1.1.1-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-aspects/3.0.5.RELEASE/spring-aspects-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-aspects/3.0.5.RELEASE/spring-aspects-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-context/3.0.5.RELEASE/spring-context-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-context/3.0.5.RELEASE/spring-context-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-expression/3.0.5.RELEASE/spring-expression-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-expression/3.0.5.RELEASE/spring-expression-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-context-support/3.0.5.RELEASE/spring-context-support-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-context-support/3.0.5.RELEASE/spring-context-support-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-test/3.0.5.RELEASE/spring-test-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-test/3.0.5.RELEASE/spring-test-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-jdbc/3.0.5.RELEASE/spring-jdbc-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-jdbc/3.0.5.RELEASE/spring-jdbc-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-tx/3.0.5.RELEASE/spring-tx-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-tx/3.0.5.RELEASE/spring-tx-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-orm/3.0.5.RELEASE/spring-orm-3.0.5.RELEASE.jar" sourcepath="M2_REPO/org/springframework/spring-orm/3.0.5.RELEASE/spring-orm-3.0.5.RELEASE-sources.jar"/> 
    <classpathentry kind="var" path="M2_REPO/org/springframework/spring-web/3.0.5.RELEASE/spring-web-3.0.5.RELEASE.jar" sourcepath="/SPRING_SOURCE_3.0.1/org.springframework.web-sources-3.0.1.RELEASE-A.jar"/> 
    <classpathentry kind="var" path="M2_REPO/commons-codec/commons-codec/1.4/commons-codec-1.4.jar"/> 
    <classpathentry kind="lib" path="D:/ProgramJR/spring/servlet-api-2.5.jar" sourcepath="C:/Users/sasikumar.s/.m2/repository/javax/servlet/servlet-api/2.5/servlet-api-2.5-sources.jar"/> 
    <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.6"> 
     <attributes> 
      <attribute name="owner.project.facets" value="java"/> 
     </attributes> 
    </classpathentry> 
    <classpathentry kind="con" path="org.eclipse.jst.j2ee.internal.web.container"/> 
    <classpathentry kind="output" path="build/classes"/> 
</classpath> 

但是，當我加入WEB-INF/lib文件夾罐子，應用程序正常運行（無法找到上述錯誤）

。

請澄清「在Build Path中添加jar」和WEB-INF/lib文件夾之間的區別。我不想爲每個項目添加罐子。

感謝您的幫助。

Answer 1

Eclipse需要知道本地maven倉庫的路徑。因此必須設置類路徑變量M2_REPO。執行以下命令：

mvn -Declipse.workspace=<path-to-eclipse-workspace> eclipse:add-maven-repo 

您還可以在eclipse中定義一個新的classpath變量：從菜單欄中選擇Window> Preferences。選擇Java > Build Path > Classpath Variables page。

然後通過執行MVN Eclipse構建項目：月食

刷新Eclipse項目，和你去那裏！