Why do I get "Exception in thread "main" java.lang.NoClassDefFoundError: org/openqa/selenium/WebDriver"?

Question

我在这里尝试了其他类似问题的一些建议，但未能解决问题。尝试通过以下方式执行 jar 时出现此错误：

java -jar AutoHotRouter-1.0.jar

鉴于以下 pom.xml，我在这里缺少什么？？

<?xml version="1.0" encoding="UTF-8"?>

<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>com.ttt</groupId>
    <artifactId>AutoHotRouter</artifactId>
    <version>1.0</version>
    <packaging>jar</packaging>

    <name>AutoHotRouter</name>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>2.11.2</version>
        </dependency>
        <dependency>
            <groupId>org.seleniumhq.selenium</groupId>
            <artifactId>selenium-api</artifactId>
            <version>2.53.1</version>
        </dependency>
        <dependency>
            <groupId>org.seleniumhq.selenium</groupId>
            <artifactId>selenium-chrome-driver</artifactId>
            <version>2.53.1</version>
        </dependency>
    </dependencies>

    <build>
        <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
            <plugins>
                <!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
                <plugin>
                    <artifactId>maven-clean-plugin</artifactId>
                    <version>3.1.0</version>
                </plugin>
                <!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
                <plugin>
                    <artifactId>maven-resources-plugin</artifactId>
                    <version>3.0.2</version>
                </plugin>
                <plugin>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>3.8.0</version>
                </plugin>
                <plugin>
                    <artifactId>maven-surefire-plugin</artifactId>
                    <version>2.22.1</version>
                </plugin>
                <plugin>
                    <artifactId>maven-install-plugin</artifactId>
                    <version>2.5.2</version>
                </plugin>
                <plugin>
                    <artifactId>maven-deploy-plugin</artifactId>
                    <version>2.8.2</version>
                </plugin>
                <plugin>
                    <artifactId>maven-site-plugin</artifactId>
                    <version>3.7.1</version>
                </plugin>
                <plugin>
                    <artifactId>maven-project-info-reports-plugin</artifactId>
                    <version>3.0.0</version>
                </plugin>
            </plugins>
        </pluginManagement>
    </build>
</project>

首先我补充说：

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-dependency-plugin</artifactId>
    <executions>
        <execution>
            <id>copy-dependencies</id>
            <phase>prepare-package</phase>
            <goals>
                <goal>copy-dependencies</goal>
            </goals>
            <configuration>
                <outputDirectory>
                    ${project.build.directory}/libs
                </outputDirectory>
            </configuration>
        </execution>
    </executions>
</plugin>
<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-jar-plugin</artifactId>
    <configuration>
        <archive>
            <manifest>
                <addClasspath>true</addClasspath>
                <classpathPrefix>libs/</classpathPrefix>
                <mainClass>com.ttt.App</mainClass>
            </manifest>
        </archive>
    </configuration>
</plugin>

我使用

构建了 jar

mvn clean install

然后

java -jar AutoHotRouter.jar

我得到了：

Exception in thread "main" java.lang.NoClassDefFoundError: org/openqa/selenium/WebDriver

然后我删除了以前的插件并首先添加了 maven-assembly-plugin 因为它对我不起作用，所以我用 maven-shade-plugin 替换了它：

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-assembly-plugin</artifactId>
    <version>3.3.0</version>
    <executions>
        <execution>
            <phase>package</phase>
            <goals>
                <goal>single</goal>
            </goals>
            <configuration>
                <archive>
                    <manifest>
                        <addClasspath>true</addClasspath>
                        <mainClass>com.ttt.App</mainClass>
                    </manifest>
                </archive>
                <descriptorRefs>
                    <descriptorRef>jar-with-dependencies</descriptorRef>
                </descriptorRefs>
            </configuration>
        </execution>
    </executions>
</plugin>

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <executions>
        <execution>
            <goals>
                <goal>shade</goal>
            </goals>
            <configuration>
                <shadedArtifactAttached>true</shadedArtifactAttached>
                <transformers>
                    <transformer implementation=
                                         "org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                        <mainClass>com.ttt.App</mainClass>
                    </transformer>
                </transformers>
            </configuration>
        </execution>
    </executions>
</plugin>

之后

mvn clean install

然后

java -jar AutoHotRouter-1.0.jar

我得到：

no main manifest attribute

我也试过了

mvn clean compile assembly:single

与 maven-assembly-plugin.

然后我得到：

Error reading assemblies: No assembly descriptors found.

谢谢！

Answer 1

这只是一个假设，因为到目前为止 pom 看起来不错。有点可疑的部分是jar插件：

<plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-jar-plugin</artifactId>
      <version>2.1</version>
      <configuration>
      ...

您稍后似乎尝试使用 java -jar 执行创建的 jar 文件？在这种情况下，您在 pom 中定义的所有依赖项都将丢失。使用 dependency-plugin to collect the dependency jar files and use the classpath option when running the jar or use the shade-plugin 创建一个包含您的 classes 以及依赖项的 uber-jar。

使用你的 pom 让我开始 Chrome，所以依赖关系看起来不错。所以我认为您启动它的方式会导致该异常。

更新：由于您使用此设置来自动化 chrome，阴影插件似乎是最好的选择。我可以用这个 pom 和 main class 开始 chrome in src/main/java

<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>org.example</groupId>
<artifactId>HotRouter</artifactId>
<version>1.0-SNAPSHOT</version>

<name>HotRouter</name>

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>11</maven.compiler.source>
    <maven.compiler.target>11</maven.compiler.target>
</properties>

<dependencies>
    <dependency>
        <groupId>org.seleniumhq.selenium</groupId>
        <artifactId>selenium-java</artifactId>
        <version>3.141.59</version>
    </dependency>
    <dependency>
        <groupId>org.apache.logging.log4j</groupId>
        <artifactId>log4j-core</artifactId>
        <version>2.14.0</version>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <version>3.2.4</version>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                    <configuration>
                        <transformers>
                            <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                                <mainClass>org.example.StartMain</mainClass>
                            </transformer>
                        </transformers>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

主要-Class

package org.example;

import org.openqa.selenium.chrome.ChromeDriver;

public class StartMain {

  public static void main(String[] args) {
    System.setProperty("webdriver.chrome.driver", "C:/Program Files/Google/Chrome/Application/chrome.exe");

    ChromeDriver driver = new ChromeDriver();
  }
}

然后 mvn package 和 java -jar ./target/HotRouter-1.0-SNAPSHOT.jar 打开 chrome。您的配置几乎相同（我认为只缺少阴影插件的相位配置）

在 pom 的 <plugins> 部分安装 shade 插件很重要，因为它不是 the default jar life-cycle. The <pluginManagement> section is just there to configure defaults for versions and configuration. See pom reference 的一部分。因此，如果仅在该部分中，将不会自动启用其他插件。

Why do I get "Exception in thread "main" java.lang.NoClassDefFoundError: org/openqa/selenium/WebDriver"?

Why do I get "Exception in thread "main" java.lang.NoClassDefFoundError: org/openqa/selenium/WebDriver"?

maven-3

maven

selenium-webdriver