NoClassDefFoundError在运行一个有效的jar（使用依赖项编译）时，尽管在pom上具有Commons-httpClient和http组件依赖项

Question

我正在尝试通过从main方法（不在测试范围内）使用selenium webDrive来自动化一个简单的用户行为。从编译器运行以下代码时，它可以工作！但是在多个案例中运行jar时-面临以下问题（我在Ubuntu上运行，使用java 7）

线程“main”java.lang.NoClassDefFoundError中出现异常：org/apache/http/conn/HttpClientConnectionManager

@日志公共类主程序{

public  WebDriver driver = new FirefoxDriver();

public static void main(String args[]) {
 //   Injector injector = Guice.createInjector(new WebModule());

    System.out.println("Browser will soon be opened");
    MainProgram mainProgram = new MainProgram();
    mainProgram.run();

}

public void run(){

    driver.get("http://www.google.co.il");
    WebElement lookFor = driver.findElement(By.name("q"));

    if(!lookFor.isDisplayed()){
        driver.close();
      log.log(Level.WARNING,"Failed!");
    };
    driver.close();

}

}

WebDriver对pom的依赖：

    <dependency>
        <groupId>org.seleniumhq.selenium</groupId>
        <artifactId>selenium-server</artifactId>
        <version>2.42.2</version>
    </dependency>
    <dependency>
        <groupId>org.seleniumhq.selenium</groupId>
        <artifactId>selenium-java</artifactId>
        <version>2.42.2</version>
    </dependency>
    <dependency>
        <groupId>org.seleniumhq.selenium</groupId>
        <artifactId>selenium-api</artifactId>
        <version>2.42.2</version>
    </dependency>
    <dependency>
        <groupId>org.seleniumhq.selenium</groupId>
        <artifactId>selenium-firefox-driver</artifactId>
        <version>2.42.2</version>
    </dependency>

Case A

 when removed -commons-httpclient - received: HttpClientConnectionManager as follows:

<!--
        <dependency>
            <groupId>commons-httpclient</groupId>
            <artifactId>commons-httpclient</artifactId>
            <version>3.1</version>
        </dependency>-->

        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.3.4</version>
          <!--  <scope>test</scope>-->
        </dependency>


Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/http/conn/HttpClientConnectionManager
    at org.openqa.selenium.remote.HttpCommandExecutor.<init>(HttpCommandExecutor.java:99)
    at org.openqa.selenium.remote.HttpCommandExecutor.<init>(HttpCommandExecutor.java:82)
    at org.openqa.selenium.firefox.internal.NewProfileExtensionConnection.start(NewProfileExtensionConnection.java:77)

-------------------------------------------------------------------------------------------------------------------------------------------
Case B

removed both commons-httpclient + httpcomponents received HttpClientConnectionManager:

<!--        &lt;!&ndash;
        <dependency>
            <groupId>commons-httpclient</groupId>
            <artifactId>commons-httpclient</artifactId>
            <version>3.1</version>
        </dependency>&ndash;&gt;

        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.3.4</version>
          &lt;!&ndash;  <scope>test</scope>&ndash;&gt;
        </dependency>-->


liron@liron-Latitude-3330:~$ java -jar automatic-tests-4.0-SNAPSHOT-jar-with-dependencies.jar
Try
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/http/conn/HttpClientConnectionManager
    at org.openqa.selenium.remote.HttpCommandExecutor.<init>(HttpCommandExecutor.java:99)
    at org.openqa.selenium.remote.HttpCommandExecutor.<init>(HttpCommandExecutor.java:82)

---------------------------------------------------------------------------------------------------------------------------------------------

Case C
when both were added to pom - same HttpClientConnectionManager


liron@liron-Latitude-3330:~$ java -jar automatic-tests-4.0-SNAPSHOT-jar-with-dependencies.jar
Browser will soon be opened
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/http/conn/HttpClientConnectionManager
    at org.openqa.selenium.remote.HttpCommandExecutor.<init>(HttpCommandExecutor.java:99)
    at org.openqa.selenium.remote.HttpCommandExecutor.<init>(HttpCommandExecutor.java:82)
    at org.openqa.selenium.firefox.internal.NewProfileExtensionConnection.start(NewProfileExtensionConnection.java:77)


----------------------------------------------------------------------------------------------------------------------------------------------

Answer 1

添加新的谷歌番石榴对我有帮助：

<dependency>
   <groupId>com.google.guava</groupId>
   <artifactId>guava</artifactId>
   <version>21.0</version>
</dependency>

这是因为其他依赖项可以下载旧的一个Guava18版本<当然，正如testphreak所说：org。阿帕奇。httpcomponents公司

Answer 2

您应该只需要selenium-java在您的pom依赖项中。请参阅此图形@Selenium HQ，它解释了Selenium的某些部分是如何相关的。此外，Selenium本身对httpClient有依赖项，您不需要显式定义它们。如果您确实对这些有合法的需求，事情会发生冲突，您需要使用排除来清理它。

清理pom后，可以运行mvn dependency:tree查看项目中的情况。

Answer 3

昨晚我的WebDriver项目遇到了同样的问题，经过一些调试，发现它缺少以下依赖项。添加它们后，我没有再次遇到这个异常。

   <dependency>
       <groupId>org.apache.httpcomponents</groupId>
       <artifactId>httpclient</artifactId>
       <version>4.3.5</version>
   </dependency>