mvn -v执行成功，mvn help:system执行失败，是什么原因（已经折磨了两天了））

2020-05-26 04:41:13 2.9k 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

Exec Maven Plugin实战：在构建生命周期中可靠执行Java程序 Maven 构建生命周期是 Java 项目标准化交付的核心机制，其本质是将编译、测试、打包等阶段按序组织的可扩展流程。Exec Maven Plugin 作为官方推荐的轻量级执行插件，基于 Maven 内置 classpath 解析与生命周期绑定能力，实现无需外部脚本即可在指定 phase（如 validate、process-classes）中安全运行 Java 工具类。它解决了 classpath 不一致、JDK 环境差异、CI/CD 可移植性差等高频痛点，技术价值在于将零散的运维逻辑（如配置校验、Sw 阅读详情

被这个问题已经折磨了两天了，实在是受不了了。请大神帮忙看看。
下面是报错信息：

C:\Users\86132>mvn help:system

[INFO] Scanning for projects...

Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-clean-plugin/2.5/maven-clean-plugin-2.5.pom

[WARNING] Failed to retrieve plugin descriptor for org.apache.maven.plugins:maven-clean-plugin:2.5: Plugin org.apache.maven.plugins:maven-clean-plugin:2.5 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-clean-plugin:jar:2.5

Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-install-plugin/2.4/maven-install-plugin-2.4.pom

[WARNING] Failed to retrieve plugin descriptor for org.apache.maven.plugins:maven-install-plugin:2.4: Plugin org.apache.maven.plugins:maven-install-plugin:2.4 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-install-plugin:jar:2.4

Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-deploy-plugin/2.7/maven-deploy-plugin-2.7.pom

[WARNING] Failed to retrieve plugin descriptor for org.apache.maven.plugins:maven-deploy-plugin:2.7: Plugin org.apache.maven.plugins:maven-deploy-plugin:2.7 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-deploy-plugin:jar:2.7

Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-site-plugin/3.3/maven-site-plugin-3.3.pom

[WARNING] Failed to retrieve plugin descriptor for org.apache.maven.plugins:maven-site-plugin:3.3: Plugin org.apache.maven.plugins:maven-site-plugin:3.3 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-site-plugin:jar:3.3

Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-antrun-plugin/1.3/maven-antrun-plugin-1.3.pom

[WARNING] Failed to retrieve plugin descriptor for org.apache.maven.plugins:maven-antrun-plugin:1.3: Plugin org.apache.maven.plugins:maven-antrun-plugin:1.3 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-antrun-plugin:jar:1.3

Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-assembly-plugin/2.2-beta-5/maven-assembly-plugin-2.2-beta-5.pom

[WARNING] Failed to retrieve plugin descriptor for org.apache.maven.plugins:maven-assembly-plugin:2.2-beta-5: Plugin org.apache.maven.plugins:maven-assembly-plugin:2.2-beta-5 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-assembly-plugin:jar:2.2-beta-5

Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-dependency-plugin/2.8/maven-dependency-plugin-2.8.pom

[WARNING] Failed to retrieve plugin descriptor for org.apache.maven.plugins:maven-dependency-plugin:2.8: Plugin org.apache.maven.plugins:maven-dependency-plugin:2.8 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-dependency-plugin:jar:2.8

Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-release-plugin/2.5.3/maven-release-plugin-2.5.3.pom

[WARNING] Failed to retrieve plugin descriptor for org.apache.maven.plugins:maven-release-plugin:2.5.3: Plugin org.apache.maven.plugins:maven-release-plugin:2.5.3 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-release-plugin:jar:2.5.3

Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/codehaus/mojo/maven-metadata.xml

Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-metadata.xml

[WARNING] Could not transfer metadata org.apache.maven.plugins/maven-metadata.xml from/to nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public): Transfer failed for http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-metadata.xml

[WARNING] Could not transfer metadata org.codehaus.mojo/maven-metadata.xml from/to nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public): Transfer failed for http://maven.aliyun.com/nexus/content/groups/public/org/codehaus/mojo/maven-metadata.xml

[WARNING] Failure to transfer org.apache.maven.plugins/maven-metadata.xml from http://maven.aliyun.com/nexus/content/groups/public was cached in the local repository, resolution will not be reattempted until the update interval of nexus-aliyun has elapsed or updates are forced. Original error: Could not transfer metadata org.apache.maven.plugins/maven-metadata.xml from/to nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public): Transfer failed for http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-metadata.xml

[WARNING] Failure to transfer org.codehaus.mojo/maven-metadata.xml from http://maven.aliyun.com/nexus/content/groups/public was cached in the local repository, resolution will not be reattempted until the update interval of nexus-aliyun has elapsed or updates are forced. Original error: Could not transfer metadata org.codehaus.mojo/maven-metadata.xml from/to nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public): Transfer failed for http://maven.aliyun.com/nexus/content/groups/public/org/codehaus/mojo/maven-metadata.xml

[INFO] ------------------------------------------------------------------------

[INFO] BUILD FAILURE

[INFO] ------------------------------------------------------------------------

[INFO] Total time:  2.356 s

[INFO] Finished at: 2020-05-26T16:33:02+08:00

[INFO] ------------------------------------------------------------------------

[ERROR] No plugin found for prefix 'help' in the current project and in the plugin groups [org.apache.maven.plugins, org.codehaus.mojo] available from the repositories [local (D:\apache-maven\repo), nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public)] -> [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