遇到错误:java.lang.NoClassDefFoundError:com/google/common/collect/ImmutableList $ Builder

我是使用EclipseIDE和TestNG的Selenium WebDriver的新手.我目前正在通过TestNG在Eclipse中运行此示例代码:

I'm new to Selenium WebDriver using EclipseIDE with TestNG. I'm currently running this sample code in Eclipse via TestNG:

import org.openqa.selenium.By;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.testng.annotations.AfterTest;
import org.testng.annotations.BeforeTest;
import org.testng.annotations.Test;

import java.util.List;

public class CheesecakeFactory {

    FirefoxDriver driver;

    @BeforeTest
    public void startDriver() {
        driver = new FirefoxDriver();
    }

    @AfterTest
    public void stopDriver() {
        driver.close();
    }

    @Test
    public void listCheesecakes() {
        driver.get("http://www.thecheesecakefactory.com/");
        driver.findElement(By.linkText("Menu")).click();
        driver.findElement(By.linkText("Cheesecake")).click();
        List<WebElement> cheesecakes = driver.findElements(By.xpath("id('leftNav_levelTwo')//li"));

        System.out.println(cheesecakes.size() + " cheesecakes:");
        for (int i=0; i<cheesecakes.size(); i++) {
            System.out.println(i+1 + ". " + cheesecakes.get(i).getText());
        }
    }

}

但是Eclipse返回此信息:

But Eclipse returns this:

[TestNG] Running:
  C:\Users\ryan\AppData\Local\Temp\testng-eclipse--616826937\testng-customsuite.xml

FAILED CONFIGURATION: @BeforeTest startDriver
java.lang.NoClassDefFoundError: com/google/common/collect/ImmutableList$Builder
    at org.openqa.selenium.os.WindowsUtils.getPathsInProgramFiles(WindowsUtils.java:275)
    at org.openqa.selenium.firefox.internal.Executable.locateFirefoxBinaryFromPlatform(Executable.java:148)
    at org.openqa.selenium.firefox.internal.Executable.<clinit>(Executable.java:25)
    at org.openqa.selenium.firefox.FirefoxBinary.<init>(FirefoxBinary.java:60)
    at org.openqa.selenium.firefox.FirefoxBinary.<init>(FirefoxBinary.java:56)
    at org.openqa.selenium.firefox.FirefoxDriver.<init>(FirefoxDriver.java:78)
    at CheesecakeFactory.startDriver(CheesecakeFactory.java:16)
    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.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:80)
    at org.testng.internal.Invoker.invokeConfigurationMethod(Invoker.java:564)
    at org.testng.internal.Invoker.invokeConfigurations(Invoker.java:213)
    at org.testng.internal.Invoker.invokeConfigurations(Invoker.java:138)
    at org.testng.TestRunner.beforeRun(TestRunner.java:641)
    at org.testng.TestRunner.run(TestRunner.java:609)
    at org.testng.SuiteRunner.runTest(SuiteRunner.java:334)
    at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:329)
    at org.testng.SuiteRunner.privateRun(SuiteRunner.java:291)
    at org.testng.SuiteRunner.run(SuiteRunner.java:240)
    at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
    at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
    at org.testng.TestNG.runSuitesSequentially(TestNG.java:1197)
    at org.testng.TestNG.runSuitesLocally(TestNG.java:1122)
    at org.testng.TestNG.run(TestNG.java:1030)
    at org.testng.remote.RemoteTestNG.run(RemoteTestNG.java:111)
    at org.testng.remote.RemoteTestNG.initAndRun(RemoteTestNG.java:204)
    at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:175)

我不明白为什么会出现此错误.我已完成以下操作:

I don't understand why I'm getting this error. I've done the following:

1. 在Eclipse中将guava-12.0.jar文件(以及Selenium-2.25.0 Webdriver中的其他jar文件)添加为外部jar文件. (此jar文件包含ImmutableList $ Builder类)

1. Added the guava-12.0.jar file (along with the other jar files in the Selenium-2.25.0 webdriver) as an external jar file in Eclipse. (This jar file contains the ImmutableList$Builder class)

在CLASSPATH(环境变量>系统变量)中添加了此jar文件的路径

Added the path of this jar file in the CLASSPATH (Environment Variables>System Variables)

我错过了什么吗?任何帮助，我们将不胜感激.

Am I missing something? Any help is greatly appreciated.