如果我通过套件运行我的测试，他们正在运行，但如果我通过POM.xml运行相同的测试用例，我得到了以下错误，任何人都可以解释我的代码有什么问题吗？
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T E S T S
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parallel='none', perCoreThreadCount=true, threadCount=2, useUnlimitedThreads=false
Running com.example.jacoco.ERPLogin
This is Before class method
Tests run: 1, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 0.318 sec <<< FAILURE!
test(com.example.jacoco.ERPLogin) Time elapsed: 0.006 sec <<< ERROR!
java.lang.NoClassDefFoundError: org/w3c/dom/ElementTraversal
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:276)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$000(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:276)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at org.apache.xerces.parsers.AbstractDOMParser.startDocument(Unknown Source)
at org.apache.xerces.impl.dtd.XMLDTDValidator.startDocument(Unknown Source)
at org.apache.xerces.impl.XMLDocumentScannerImpl.startEntity(Unknown Source)
at org.apache.xerces.impl.XMLVersionDetector.startDocumentParsing(Unknown Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
at org.apache.xerces.parsers.DOMParser.parse(Unknown Source)
at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown Source)
at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:208)
at org.openqa.selenium.firefox.internal.FileExtension.readIdFromInstallRdf(FileExtension.java:97)
at org.openqa.selenium.firefox.internal.FileExtension.writeTo(FileExtension.java:60)
at org.openqa.selenium.firefox.internal.ClasspathExtension.writeTo(ClasspathExtension.java:63)
at org.openqa.selenium.firefox.FirefoxProfile.installExtensions(FirefoxProfile.java:416)
at org.openqa.selenium.firefox.FirefoxProfile.layoutOnDisk(FirefoxProfile.java:394)
at org.openqa.selenium.firefox.internal.NewProfileExtensionConnection.start(NewProfileExtensionConnection.java:89)
at org.openqa.selenium.firefox.FirefoxDriver.startClient(FirefoxDriver.java:246)
at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:114)
at org.openqa.selenium.firefox.FirefoxDriver.<init>(FirefoxDriver.java:191)
at org.openqa.selenium.firefox.FirefoxDriver.<init>(FirefoxDriver.java:186)
at org.openqa.selenium.firefox.FirefoxDriver.<init>(FirefoxDriver.java:182)
at org.openqa.selenium.firefox.FirefoxDriver.<init>(FirefoxDriver.java:95)
at com.example.jacoco.ERPLogin.<init>(ERPLogin.java:16)
和我的POM.xml如下，
<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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>MyGroup</groupId>
<artifactId>TestCodeCoverage</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>MyMavenProject</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<version>0.5.5.201112152213</version>
<configuration>
<destFile>${basedir}/target/coverage-reports/jacoco-unit.exec</destFile>
<dataFile>${basedir}/target/coverage-reports/jacoco-unit.exec</dataFile>
</configuration>
<executions>
<execution>
<id>jacoco-initialize</id>
<goals>
<goal>prepare-agent</goal>
</goals>
</execution>
<execution>
<id>jacoco-site</id>
<phase>package</phase>
<goals>
<goal>report</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.5</source>
<target>1.5</target>
</configuration>
</plugin>
<plugin>
<artifactId>maven-failsafe-plugin</artifactId>
<executions>
<execution>
<goals>
<goal>integration-test</goal>
<goal>verify</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.14.1</version>
<dependencies>
<dependency>
<groupId>org.apache.maven.surefire</groupId>
<artifactId>surefire-junit47</artifactId>
<version>2.12</version>
</dependency>
</dependencies>
<configuration>
<includes>
<include>**/*.class</include>
</includes>
</configuration>
</plugin>
</plugins>
</pluginManagement>
</build>
<dependencies>
<dependency>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-report-plugin</artifactId>
<version>2.17</version>
<type>maven-plugin</type>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.testng</groupId>
<artifactId>testng</artifactId>
<version>6.8</version>
</dependency>
<dependency>
<groupId>org.seleniumhq.selenium</groupId>
<artifactId>selenium-server</artifactId>
<version>2.41.0</version>
</dependency>
<dependency>
<groupId>org.seleniumhq.selenium</groupId>
<artifactId>selenium-java</artifactId>
<version>2.41.0</version>
</dependency>
<dependency>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-report-plugin</artifactId>
<version>2.5</version>
<type>maven-plugin</type>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>com.opera</groupId>
<artifactId>operadriver</artifactId>
<version>1.5</version>
<exclusions>
<exclusion>
<groupId>org.seleniumhq.selenium</groupId>
<artifactId>selenium-remote-driver</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
</dependencyManagement>
<reporting>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-report-plugin</artifactId>
<version>2.5</version>
<configuration>
<!-- <outputName>GoogleSearchTestResults</outputName> -->
<outputDirectory>${project.build.directory}/site</outputDirectory>
</configuration>
</plugin>
</plugins>
</reporting>
</project>