Maven插件无法解析

Question

我已经按照标题所述搜索了这个问题，但仍然不知道应该做什么。我正在尝试构建一个可执行的 jar 文件，但其中一个插件maven-assembly-plugin无法解析。

我已经尝试过https://maven.apache.org/plugins/maven-assemble-plugin/usage.html 但它不起作用。我把整个pom.xml文件都放了，插件在文件的底部。非常感谢任何帮助。

这是错误消息：

Plugin could not be resolved. Ensure the plugin's groupId, artifactId and 
version are present. Additional information: 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

这是文件：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema- instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>

<groupId>distributed.systems</groupId>
<artifactId>leader.election</artifactId>
<version>0.0.1-SNAPSHOT</version>

<name>leader.election</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>

<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
</properties>

<dependencies>
<dependency>
  <groupId>junit</groupId>
  <artifactId>junit</artifactId>
  <version>4.11</version>
  <scope>test</scope>
</dependency>

<dependency>
  <groupId>org.apache.zookeeper</groupId>
  <artifactId>zookeeper</artifactId>
  <version>3.6.1</version>
</dependency>
</dependencies>
<build>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
  <plugins>
    <!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
    <plugin>
      <artifactId>maven-clean-plugin</artifactId>
      <version>3.1.0</version>
    </plugin>
    <!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
    <plugin>
      <artifactId>maven-resources-plugin</artifactId>
      <version>3.0.2</version>
    </plugin>
    <plugin>
      <artifactId>maven-compiler-plugin</artifactId>
      <version>3.8.0</version>
    </plugin>
    <plugin>
      <artifactId>maven-surefire-plugin</artifactId>
      <version>2.22.1</version>
    </plugin>
    <plugin>
      <artifactId>maven-jar-plugin</artifactId>
      <version>3.0.2</version>
    </plugin>
    <plugin>
      <artifactId>maven-install-plugin</artifactId>
      <version>2.5.2</version>
    </plugin>
    <plugin>
      <artifactId>maven-deploy-plugin</artifactId>
      <version>2.8.2</version>
    </plugin>
    <!-- site lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
    <plugin>
      <artifactId>maven-site-plugin</artifactId>
      <version>3.7.1</version>
    </plugin>
    <plugin>
      <artifactId>maven-project-info-reports-plugin</artifactId>
      <version>3.0.0</version>
    </plugin>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-compiler-plugin</artifactId>
      <version>3.8.0</version>
        <configuration>
            <release>14</release>
        </configuration>
    </plugin>
    <plugin>
      <artifactId>maven-assembly-plugin</artifactId>
      <version>3.3.0</version>
      <executions>
        <execution>
          <phase>package</phase>
          <goals>
            <goal>single</goal>
          </goals>
        </execution>
      </executions>
      <configuration>
        <archive>
          <manifest>
            <mainClass>LeaderElection</mainClass>
          </manifest>
        </archive>
        <descriptorRefs>
          <descriptorRef>jar-with-dependencies</descriptorRef>
        </descriptorRefs>
      </configuration>
    </plugin> 
  </plugins>
</pluginManagement>

Answer 1

您可能正在使用旧的 Maven 版本，该版本尝试通过 HTTP 协议获取插件。几个月前该功能已被禁用。您必须使用更新版本的 Maven 或更改本地配置文件~/.m2/settings.xml（或C:\users\you\.m2\settings.xml）以使用 HTTPS。如果没有这样的文件，您可以通过复制示例来创建它：

<settings xmlns="http://maven.apache.org/SETTINGS/1.1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.1.0 http://maven.apache.org/xsd/settings-1.1.0.xsd">
    <profiles>
        <profile>
            <id>stefan</id>
            <activation>
                <activeByDefault>true</activeByDefault>
            </activation>
            <repositories>

                <repository>
                    <id>central</id>
                    <url>https://repo1.maven.org/maven2</url>
                    <releases>
                      <updatePolicy>never</updatePolicy>
                    </releases>
                    <snapshots>
                      <enabled>false</enabled>
                    </snapshots>
                </repository>  
 
                <repository>
                    <id>spring-milestones</id>
                    <url>https://repo.springsource.org/libs-milestone/</url>
                    <releases>
                      <updatePolicy>never</updatePolicy>
                    </releases>
                    <snapshots>
                      <enabled>false</enabled>
                    </snapshots>
                </repository>
 
                <repository>
                    <id>jboss</id>
                    <url>https://repository.jboss.org/nexus/content/groups/public/</url>
                    <releases>
                      <updatePolicy>never</updatePolicy>
                    </releases>
                    <snapshots>
                      <enabled>false</enabled>
                    </snapshots>
                </repository>                
            </repositories>    
 
            <pluginRepositories>
                <pluginRepository>
                    <id>central</id>
                    <url>https://repo1.maven.org/maven2</url>
                    <releases>
                      <updatePolicy>never</updatePolicy>
                    </releases>
                    <snapshots>
                      <enabled>false</enabled>
                    </snapshots>
                </pluginRepository> 
            </pluginRepositories>
            
        </profile>
    </profiles>    
</settings>