使用maven，如何将war配置为ear文件

<project>
  ...
  <packaging>ear</packaging>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-ear-plugin</artifactId>
        <version>3.1.0</version>
        <configuration>
          <modules>
            <webModule>
              <groupId>your.web.module.groupId</groupId>
              <artifactId>your-web-module-artifactId</artifactId>
              <contextRoot>/your-web-context-root</contextRoot>
            </webModule>
          </modules>
        </configuration>
      </plugin>
    </plugins>
  </build>
  ...
</project>

mvn clean package