使用mvn devserver的Google App Engine Java失敗：缺少“guestbook / target / guestbook-1.0-SNAPSHOT”

Question

我正在嘗試使用Java在Google App Engine上進行簡單的教程 ，但是當我嘗試運行mvn appengine:devserver命令時，我得到了這個奇怪的丟失目錄錯誤：

[INFO] guestbook ......................................... FAILURE [  0.228 s]
[INFO] guestbook-war ..................................... SKIPPED
[INFO] guestbook-ear ..................................... SKIPPED
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.446 s
[INFO] Finished at: 2014-05-06T12:03:51-08:00
[INFO] Final Memory: 9M/176M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal com.google.appengine:appengine-maven-plugin:1.9.4:devserver (default-cli) on project guestbook: The application directory does not exist : /Users/davidt/GoogleAppEngineProjects/guestbook/target/guestbook-1.0-SNAPSHOT -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[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

到底是怎么回事？ 我什么時候應該創建該快照？

注意：我不確定這是否重要，但我一直在同一文件夾下多次刪除並重新創建項目。

Answer 1

你必須在guestbook-ear文件夾中運行mvn appengine:devserver 。 我在頂層運行它。