执行 Maven install 时报错：
Failed to execute goalorg.apache.maven.plugins:maven-gpg-plugin:1.4:sign (sign-artifacts)on project openstack-java-sdk: Cannot obtain passphrase in batchmode -> [Help 1]
如下：
[INFO] BUILD FAILURE
[INFO]------------------------------------------------------------------------
[INFO] Total time: 0.970s
[INFO] Finished at: Tue Mar 04 14:06:04 CST 2014
[INFO] Final Memory: 7M/87M
[INFO]------------------------------------------------------------------------
[ERROR] Failed to execute goalorg.apache.maven.plugins:maven-gpg-plugin:1.4:sign (sign-artifacts)on project openstack-java-sdk: Cannot obtain passphrase in batchmode -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Mavenwith the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debuglogging.
[ERROR]
[ERROR] For more information about the errors and possiblesolutions, please read the following articles:
[ERROR] [Help 1]http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException
原因： 使用的版本是maven3.X,其执行maven-ant-plugin的行为和maven2.x有一定的不同，需要引入pluginManagement
解决办法是：在pom.xml中引入：
之前的内容：
<build>
<plugins>
<plugin></plugin>
...
<plugin></plugin>
</plugins>
</build>
修改后的内容：
<build>
<pluginManagement>
<plugins>
<plugin></plugin>
...
<plugin></plugin>
</plugins>
</pluginManagement>
</build>