运行 Google App Engine 快速入门时出错：缺少 com.google.appengine:appengine-maven-plugin:jar:1.9.24 的 POM答案

【问题标题】：Error running Google App Engine quickstart : POM for com.google.appengine:appengine-maven-plugin:jar:1.9.24 is missing运行 Google App Engine 快速入门时出错：缺少 com.google.appengine:appengine-maven-plugin:jar:1.9.24 的 POM
【发布时间】：2015-07-23 01:22:58
【问题描述】：

任何帮助我克服此错误的帮助将不胜感激。谷歌搜索似乎没有出现任何有用的结果。我在运行 OSX Yosemite 并使用 Java 1.7.0_71 和 Maven 3.3 的 Macbook Pro 上。 Maven 是通过 HomeBrew 安装的。

为了了解 Google App Engine，我按照https://cloud.google.com/appengine/docs/java/gettingstarted/introduction 的快速入门说明进行操作，并顺利到达https://cloud.google.com/appengine/docs/java/gettingstarted/ui_and_code 的页面说明。创建 guestbook.jsp 文件并运行 mvn appengine:devserver 后，我得到以下构建失败。

[INFO] Scanning for projects...
[WARNING] The POM for com.google.appengine:appengine-maven-plugin:jar:1.9.24 is missing, no dependency information available
[WARNING] Failed to retrieve plugin descriptor for com.google.appengine:appengine-maven-plugin:1.9.24: Plugin com.google.appengine:appengine-maven-plugin:1.9.24 or one of its dependencies could not be resolved: Failure to find com.google.appengine:appengine-maven-plugin:jar:1.9.24 in https://repo.maven.apache.org/maven2 was cached in the local repository, resolution will not be reattempted until the update interval of central has elapsed or updates are forced
Downloading: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-metadata.xml
Downloading: https://repo.maven.apache.org/maven2/org/codehaus/mojo/maven-metadata.xml
Downloaded: https://repo.maven.apache.org/maven2/org/codehaus/mojo/maven-metadata.xml (20 KB at 4.3 KB/sec)
Downloaded: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-metadata.xml (13 KB at 2.2 KB/sec)
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 6.435 s
[INFO] Finished at: 2015-07-22T21:10:29-04:00
[INFO] Final Memory: 10M/245M
[INFO] ------------------------------------------------------------------------
[ERROR] No plugin found for prefix 'appengine' in the current project and in the plugin groups [org.apache.maven.plugins, org.codehaus.mojo] available from the repositories [local (/Users/nissandookeran/.m2/repository), central (https://repo.maven.apache.org/maven2)] -> [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/NoPluginFoundForPrefixException

【问题讨论】：

标签： java maven google-app-engine

【解决方案1】：

Appengine Maven 插件 hasn't been deployed to Maven Central yet 的 1.9.24 版，无论出于何种原因。可能最简单的做法是打开你的 pom.xml，找到它正在使用的 appengine-maven-plugin 的 <version>，并让它使用 1.9.23 而不是 ${appengine.version} 或 1.9.24 或任何它正在使用的东西。

【讨论】：

【解决方案2】：

如果是新版本，也可以尝试运行mvn appengine:devserver -U

【讨论】：

Official reference：如果失败表明缺少 App Engine Maven 插件，这可能是因为最近将新版本推送到 Maven 存储库。要解决此问题，请使用 -U 选项调用 Maven：mvn appengine:devserver -U

【解决方案3】：

您必须在 pom 文件中包含以下内容

        <plugin>
           <groupId>com.google.cloud.tools</groupId>
           <artifactId>appengine-maven-plugin</artifactId>
           <version>1.9.48</version>
        </plugin>

【讨论】：