maven在cmd下运行mvn出现 No goals have been specified for this build.

[阿奇XS]

1，初学maven，环境变量都已经配置好了，而且运行mvn -version都没有问题
2，在cmd下运行mvn出现 No goals have been specified for this build.已经困扰我几天了，
这个问题没法让我继续往下学了，特在此求助前辈同仁们。
C:\Documents and Settings\zhouyu>mvn
[INFO] Scanning for projects...
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.343s
[INFO] Finished at: Sun Nov 13 10:35:13 CST 2011
[INFO] Final Memory: 1M/4M
[INFO] ------------------------------------------------------------------------
[ERROR] No goals have been specified for this build. You must specify a valid li
fecycle phase or a goal in the format <plugin-prefix>:<goal> or <plugin-group-id
>:<plugin-artifact-id>[:<plugin-version>]:<goal>. Available lifecycle phases are
: validate, initialize, generate-sources, process-sources, generate-resources, p
rocess-resources, compile, process-classes, generate-test-sources, process-test-
sources, generate-test-resources, process-test-resources, test-compile, process-
test-classes, test, prepare-package, package, pre-integration-test, integration-
test, post-integration-test, verify, install, deploy, pre-clean, clean, post-cle
an, pre-site, site, post-site, site-deploy. -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e swit
ch.
[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 rea
d the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/NoGoalSpecifie
dException

[icare]

No goals have been specified for this build. You must specify a valid li
fecycle phase or a goal in the format <plugin-prefix>:<goal> or <plugin-group-id
>:<plugin-artifact-id>[:<plugin-version>]:<goal>. Available lifecycle phases are
: validate, initialize, generate-sources, process-sources, generate-resources, p
rocess-resources, compile, process-classes, generate-test-sources, process-test-
sources, generate-test-resources, process-test-resources, test-compile, process-
test-classes, test, prepare-package, package, pre-integration-test, integration-
test, post-integration-test, verify, install, deploy, pre-clean, clean, post-cle
an, pre-site, site, post-site, site-deploy. 这段讲得很清楚啊

[kouyiSC]

引用

在pom.xml文件<build>标签后面加上<defaultGoal>compile</defaultGoal>即可。

其实使用命令行时就已经指定了phase，而使用m2eclipse的【Run As】-【Maven build】时并未为其指定goal或phase，所以才报这个错误。

去看看这几个原因 应该有一个是你的错误：
http://www.17ext.com/answer/79576.aspx
http://yusudong.iteye.com/blog/1129914http://aaagu1234.iteye.com/blog/1070760
http://www.iteye.com/problems/71530

[仿秀达人]

帮你顶一下吧， 没听过这个东东，不知道是做什么用的

[阿奇XS]

谢谢你关注此贴，maven构建标准项目结构

[hylan_woo]

我也遇到这个问题，但是我是在自己新建的原型上建项目 才会遇到这个问题