如何在maven目标目录的JAR文件中运行java类

Question

我想在maven构建后运行我的Izpack安装程序，但我在执行"mvn测试"后得到以下输出:

[INFO] Scanning for projects...
[INFO] ------------------------------------------------------------------------
[INFO] Building RS IzPack installer
[INFO]    task-segment: [test]
[INFO] ------------------------------------------------------------------------
[debug] execute contextualize
[INFO] [resources:copy-resources {execution: copy-resources}]
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 109 resources
[INFO] Copying 4 resources
[INFO] Preparing exec:java
[WARNING] Removing: java from forked lifecycle, to prevent recursive invocation.
[debug] execute contextualize
[INFO] [resources:copy-resources {execution: copy-resources}]
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 109 resources
[INFO] Copying 4 resources
[INFO] [exec:java {execution: default}]
[WARNING]
java.lang.ClassNotFoundException: com.izforge.izpack.installer.Installer
        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 java.lang.ClassLoader.loadClass(ClassLoader.java:251)
        at org.codehaus.mojo.exec.ExecJavaMojo$1.run(ExecJavaMojo.java:285)
        at java.lang.Thread.run(Thread.java:595)
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] An exception occured while executing the Java class. com.izforge.izpack.installer.Installer

看起来我必须以某种方式将生成的jar文件放入类路径，有什么想法吗?

节选自my pom.xml:

  <plugin>
    <groupId>org.codehaus.mojo</groupId>
    <artifactId>exec-maven-plugin</artifactId>
    <version>1.2.1</version>
    <executions>
      <execution>
        <phase>test</phase>
        <goals>
          <goal>java</goal> <!-- "exec" also possible -->
        </goals>
        <configuration>
          <mainClass>com.izforge.izpack.installer.Installer</mainClass>
          <arguments>
            <argument>-console</argument>
            <!-- <argument>arg1</argument> -->
          </arguments>
        </configuration>
      </execution>
    </executions>
  </plugin>

Apache Maven 2.2.1 (r801777;2009-08-06 21:16:01 + 0200)Java版本:1.6.0_20Java home: C:Javajdk16jre默认区域设置:en_GB，平台编码:Cp1252操作系统名称:"windows xp"版本:"5.1" arch: "x86" Family: "windows" 马丁

Answer 1

你看过罐子里面吗?可能是maven没有将需要的类包含到jar中。

Answer 2

我认为您应该使用-classpath为java命令定义类路径。你需要构建一个类路径，它将包含你的主类com.izforge.izpack.installer.Installer和它的所有依赖。它可以在一个jar、一个类文件夹或多个jar中。关于如何定义java调用的类路径，请参阅Wikipedia。

Answer 3

您可以使用类似的东西来定义该执行的依赖项:

<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.2.1</version>
<executions>
  <execution>
    <phase>test</phase>
    <goals>
      <goal>java</goal> <!-- "exec" also possible -->
    </goals>
    <configuration>
      <mainClass>com.izforge.izpack.installer.Installer</mainClass>
      <arguments>
        <argument>-console</argument>
        <!-- <argument>arg1</argument> -->
      </arguments>
    </configuration>
  </execution>
</executions>
<dependencies>
  <dependency>
    <groupId>org.codehaus.izpack</groupId>
    <artifactId>izpack-standalone-compiler</artifactId>
    <version>4.3.4</version>
    <scope>compile</scope>
  </dependency>
</dependencies>

但是izpack也有一个Maven插件