在eclipse中的项目上运行生成器“Maven Project builder”时出错

Question

我想创建一个在eclipse中使用Lifeay-maven-plugin的Liveay插件portlet，但每次我尝试这样做时，我都会遇到这个错误：

Errors occurred during the build.
Errors running builder 'Maven Project Builder' on project 'sample-portlet'.
Could not calculate build plan: Plugin com.liferay.maven.plugins:liferay-maven-plugin:6.2.1 or one of its dependencies could not be resolved: Failure to find com.liferay.maven.plugins:liferay-maven-plugin:jar:6.2.1 in http://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
Plugin com.liferay.maven.plugins:liferay-maven-plugin:6.2.1 or one of its dependencies could not be resolved: Failure to find com.liferay.maven.plugins:liferay-maven-plugin:jar:6.2.1 in http://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
Could not calculate build plan: Plugin com.liferay.maven.plugins:liferay-maven-plugin:6.2.1 or one of its dependencies could not be resolved: Failure to find com.liferay.maven.plugins:liferay-maven-plugin:jar:6.2.1 in http://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
Plugin com.liferay.maven.plugins:liferay-maven-plugin:6.2.1 or one of its dependencies could not be resolved: Failure to find com.liferay.maven.plugins:liferay-maven-plugin:jar:6.2.1 in http://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

Answer 1

maven似乎不再支持不安全的协议，所以我将maven存储库URL从http更改为https，这对我很有用。

<mirror>
<id>nexus</id>
<mirrorOf>*</mirrorOf>
<url>https://repo.maven.apache.org/maven2/</url>
</mirror>

查看以下链接了解更多信息https://links.sonatype.com/central/501-https-required

Answer 2

当我尝试创建Maven项目时，我在使用Eclipse（实际上是Spring工具套件[STS]）时遇到了类似的错误

Could not calculate build plan: Plugin org.apache.maven.plugins:maven-war-plugin:3.2.1 or one of its dependencies could not be resolved ...

看起来maven不喜欢http（我在某个时候使用.m2/setting.xml设置了http），并且拒绝下载它所需要的内容。

501 HTTPS Required. 
Use https://repo.maven.apache.org/maven2/
More information at https://links.sonatype.com/central/501-https-required

上述网站告诉我：

Effective January 15, 2020, The Central Repository no longer supports insecure 
communication over plain HTTP and requires that all requests to the repository are 
encrypted over HTTPS.

所以我把http改成了https

但是我仍然需要将maven证书导入java信任库。为此，我导出了repo.maven.apache.org证书并使用Java“keytools”命令导入它。

这里我列出了一种进行证书导入的方法。

Spring工具套件-SunCertPathBuilderException：找不到请求目标的有效证书路径

作为最后一步，我必须重新启动STS。从那以后，它似乎对我有用。

对我来说，这里的教训是从一开始就在需要的地方使用https，这样我就不会遇到这样的问题。

Answer 3

1. 接近日食
2. 转到您的主目录（例如Windows上的C：/user/your_user_name）
3. 查找并删除. m2/repository文件夹
4. 确保您连接到互联网
5. 开始日食
6. 保持互联网连接并让maven更新所有依赖项