java.lang.ClassNotFoundException: org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter when starting Simple Struts2 Application
eclipse, java, maven, struts2, tomcat
Solution
Use this command to convert Maven project to Dynamic Web Project for Eclipse:
mvn eclipse:eclipse -Dwtpversion=3.4.2
you may change whatever WTP version you use
`.classpath` should be like this
<classpath>
<classpathentry kind="src" path="src/main/java" including="**/*.java"/>
<classpathentry kind="src" path="src/main/resources" excluding="**/*.java"/>
<classpathentry kind="output" path="target/classes"/>
<classpathentry kind="var" path="M2_REPO/asm/asm/3.3/asm-3.3.jar"/>
<classpathentry kind="var" path="M2_REPO/asm/asm-commons/3.3/asm-commons-3.3.jar"/>
<classpathentry kind="var" path="M2_REPO/asm/asm-tree/3.3/asm-tree-3.3.jar"/>
<classpathentry kind="var" path="M2_REPO/commons-fileupload/commons-fileupload/1.2.2/commons-fileupload-1.2.2.jar" />
<classpathentry kind="var" path="M2_REPO/commons-io/commons-io/2.0.1/commons-io-2.0.1.jar"/>
<classpathentry kind="var" path="M2_REPO/commons-lang/commons-lang/2.5/commons-lang-2.5.jar"/>
<classpathentry kind="var" path="M2_REPO/org/freemarker/freemarker/2.3.18/freemarker-2.3.18.jar"/>
<classpathentry kind="var" path="M2_REPO/javassist/javassist/3.11.0.GA/javassist-3.11.0.GA.jar"/>
<classpathentry kind="var" path="M2_REPO/junit/junit/3.8.1/junit-3.8.1.jar"/>
<classpathentry kind="var" path="M2_REPO/ognl/ognl/3.0.4/ognl-3.0.4.jar"/>
<classpathentry kind="var" path="M2_REPO/org/apache/struts/struts2-core/2.3.1.2/struts2-core-2.3.1.2.jar"/>
<classpathentry kind="lib" path="C:/Program Files/Java/jdk1.6.0_32/lib/tools.jar"/>
<classpathentry kind="var" path="M2_REPO/org/apache/struts/xwork/xwork-core/2.3.1.2/xwork-core-2.3.1.2.jar"/>
<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
</classpath>
After build the WAR file should deploy to `%CATALINA_BASE%\webapps`.
Problem
I am trying to run a simple Struts2 application but it always throw the following exception: ``` java.lang.ClassNotFoundException: org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter ``` I have followed the step by step tutorial in Create Struts 2 Web Application Using Maven To Manage Artifacts and To Build The Application, but I cannot make it work. I also managed to find other Struts2 tutorial which uses maven but all failed. It throws the same exception when I try to run the application. I used the following: - Eclipse - Maven - Tomcat - Struts2 According to other discussions, the dependencies jar files(e.g. struts2-core) must be put on the lib folder but as for me, I am using Maven so all the dependencies are already included in my build path under Maven Dependencies. I even tried running the sample project given in Struts2 website (Basic_Struts_2_Maven_2_3_1_2.zip) but I still have no luck. Building it is successful but running it on server always fail. Am I missing anything? Here's the `web.xml`: ``` <?xml version="1.0" encoding="UTF-8"?> <web-app id="WebApp_ID" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> <display-name>Basic_Struts2_Maven</display-name> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> <filter> <filter-name>struts2</filter-name> <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class> </filter> <filter-mapping> <filter-name>struts2</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> </web-app> ``` `pom.xml`: ``` <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>manning</groupId> <artifactId>Basic_Struts2_Mvn</artifactId> <packaging>war</packaging> <version>0.0.1-SNAPSHOT</version> <name>Basic Struts 2</name> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> </properties> <build> <finalName>Basic_Struts2_Mvn</finalName> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>2.3.2</version> <configuration> <source>1.6</source> <target>1.6</target> </configuration> </plugin> </plugins> </build> <dependencies> <dependency> <groupId>org.apache.struts</groupId> <artifactId>struts2-core</artifactId> <version>2.3.1.2</version> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.14</version> </dependency> </dependencies> </project> ``` `struts.xml`: ``` <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" "http://struts.apache.org/dtds/struts-2.0.dtd"> <struts> <constant name="struts.devMode" value="true" /> <package name="basicstruts2" extends="struts-default"> <action name="index"> <result>/index.jsp</result> </action> </package> </struts> ``` `.classpath`: ``` <?xml version="1.0" encoding="UTF-8"?> <classpath> <classpathentry kind="src" output="target/classes" path="src/main/java"/> <classpathentry excluding="**" kind="src" output="target/classes" path="src/main/resources"/> <classpathentry kind="src" output="target/test-classes" path="src/test/java"/> <classpathentry excluding="**" kind="src" output="target/test-classes" path="src/test/resources"/> <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.5"/> <classpathentry kind="con" path="org.maven.ide.eclipse.MAVEN2_CLASSPATH_CONTAINER"/> <classpathentry kind="con" path="org.eclipse.jst.j2ee.internal.web.container"/> <classpathentry kind="con" path="org.eclipse.jst.j2ee.internal.module.container"/> <classpathentry kind="output" path="target/classes"/> </classpath> ```