当我在谷歌 Appengine 中运行命令“mvn appengine:devserver”构建失败？

Question

我正在尝试使用 java 完成关于谷歌应用引擎的简单教程： 但是当我尝试运行 mvn appengine:devserver 命令时，我得到了这个奇怪的丢失目录错误：

[INFO] Scanning for projects...
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Build Order:
[INFO] 
[INFO] guestbook
[INFO] guestbook-war
[INFO] guestbook-ear
[INFO] 
[INFO] Using the builder org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder with a thread count of 1
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building guestbook 1.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] >>> appengine-maven-plugin:1.9.0:devserver (default-cli) @ guestbook >>>
[INFO] 
[INFO] <<< appengine-maven-plugin:1.9.0:devserver (default-cli) @ guestbook <<<
[INFO] 
[INFO] --- appengine-maven-plugin:1.9.0:devserver (default-cli) @ guestbook ---
[INFO] 
[INFO] Google App Engine Java SDK - Running Development Server
[INFO] 
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO] 
[INFO] guestbook ......................................... FAILURE [  0.768 s]
[INFO] guestbook-war ..................................... SKIPPED
[INFO] guestbook-ear ..................................... SKIPPED
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.507 s
[INFO] Finished at: 2014-11-04T22:56:48+05:30
[INFO] Final Memory: 9M/158M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal com.google.appengine:appengine-maven-plugin:1.9.0:devserver (default-cli) on project guestbook: The application directory does not exist : /home/e100086/gooru_OAuth/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

Answer 1

mvn appengine:devserver 预计将在 guestbook-ear 项目文件夹上运行。看起来您正在 guestbook 文件夹上运行它。

编辑：this 的可能重复项？