title: Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.2.1:exec
body: <p>I needed to build Cloudstack from source and followed <a href="http://docs.cloudstack.apache.org/en/master/developer_guide.html#installing-from-source" rel="nofollow">this article</a> in the documentation. But everytime I built it with maven, I got stuck with following error. Guessing as a solution, I tried this build with oracle jdk-8, openjdk-7 and openjdk6. And also tried tomcat6 and tomcat8. But got no solution. What is going wrong? I think the reason could be a problem with a plugin but have no idea how to solve. I searched online for this error, but got no workaround.</p>
  
  <pre><code>[ERROR] Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.2.1:exec (compile) on project cloud-apidoc: Command execution failed. Process exited with an error: 1 (Exit value: 1) -&gt; [Help 1]
  org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.2.1:exec (compile) on project cloud-apidoc: Command execution failed.
      at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:217)
      at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
      at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
      at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:84)
      at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:59)
      at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBuild(LifecycleStarter.java:183)
      at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:161)
      at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:320)
      at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
      at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537)
      at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
      at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.lang.reflect.Method.invoke(Method.java:483)
      at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
      at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
      at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
      at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
  Caused by: org.apache.maven.plugin.MojoExecutionException: Command execution failed.
      at org.codehaus.mojo.exec.ExecMojo.execute(ExecMojo.java:362)
      at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:101)
      at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:209)
      ... 19 more
  Caused by: org.apache.commons.exec.ExecuteException: Process exited with an error: 1 (Exit value: 1)
      at org.apache.commons.exec.DefaultExecutor.executeInternal(DefaultExecutor.java:377)
      at org.apache.commons.exec.DefaultExecutor.execute(DefaultExecutor.java:160)
      at org.codehaus.mojo.exec.ExecMojo.executeCommandLine(ExecMojo.java:610)
      at org.codehaus.mojo.exec.ExecMojo.execute(ExecMojo.java:352)
      ... 21 more
  [ERROR] 
  [ERROR] Re-run Maven using the -X switch to enable full debug logging.
  [ERROR] 
  [ERROR] For more information about the errors and possible solutions, please read the following articles:
  [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
  [ERROR] 
  [ERROR] After correcting the problems, you can resume the build with the command
  [ERROR]   mvn &lt;goals&gt; -rf :cloud-apidoc
  </code></pre>
  
  <p>Thank you.</p>