Struts2-Maven in the Eclipse IDE

I imported this Struts2-maven project into my Eclipse.

here is mine pom.xmlfor struts2

<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>Form_Tags_Struts2_Mvn</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>Form_Tags_Struts2_Mvn</name>
<build>
    <finalName>Form_Tags_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>com.sun</groupId>
        <artifactId>tools</artifactId>
        <version>1.7.0_05</version>
        <scope>system</scope>
        <systemPath>/usr/lib/jvm/jdk1.7.0_05/lib/tools.jar</systemPath>
    </dependency>
    <dependency>
        <groupId>org.apache.struts</groupId>
        <artifactId>struts2-core</artifactId>
        <version>2.3.1.2</version>
    </dependency>
        </dependencies>
<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>

But when I try to run, it shows an exception. Here is my exception:

SEVERE: struts2 java.lang.ClassNotFoundException: org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter     at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714)     at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)     at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:532)     at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:514)     at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:133)     at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:256)     at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:382)     at org.apache.catalina.core.ApplicationFilterConfig. (ApplicationFilterConfig.java:103)     at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4650)      org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5306)      org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)     at org.apache.catalina.core.ContainerBase $StartChild.call(ContainerBase.java:1559)     at org.apache.catalina.core.ContainerBase $StartChild.call(ContainerBase.java:1549)      java.util.concurrent.FutureTask $Sync.innerRun(FutureTask.java:334)      java.util.concurrent.FutureTask.run(FutureTask.java:166)      java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)      java.util.concurrent.ThreadPoolExecutor $Worker.run(ThreadPoolExecutor.java:603)      java.lang.Thread.run(Thread.java:722)

- ? ?