title: Failed to read artifact descriptor for org.apache.maven.plugins:maven-source-plugin:jar:2.4
body: <p>Thanks to a Dropwizard Maven archetype I generated a sample Dropwizard Maven project. The pom.xml notably uses maven-source-plugin:</p>
  
  <pre><code>&lt;plugin&gt;
      &lt;artifactId&gt;maven-source-plugin&lt;/artifactId&gt;
      &lt;version&gt;2.4&lt;/version&gt;
      &lt;executions&gt;
          &lt;execution&gt;
             &lt;id&gt;attach-sources&lt;/id&gt;
             &lt;goals&gt;
                &lt;goal&gt;jar&lt;/goal&gt;
             &lt;/goals&gt;
          &lt;/execution&gt;
      &lt;/executions&gt;
  &lt;/plugin&gt;
  </code></pre>
  
  <p>When I run "clean install" I have the following error :</p>
  
  <blockquote>
    <p>Plugin org.apache.maven.plugins:maven-source-plugin:2.4 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-source-plugin:jar:2.4: Could not transfer artifact org.apache.maven.plugins:maven-source-plugin:pom:2.4 from/to central (<a href="http://repo.maven.apache.org/maven2" rel="noreferrer">http://repo.maven.apache.org/maven2</a>): Connection refused: connect -> [Help 1]</p>
  </blockquote>
  
  <p>The "maven-source-plugin" dependency is stored in the Nexus repository of my company. So I tried the adding of the plugin dependency between dependencies and /dependencies :</p>
  
  <pre><code>&lt;dependencies&gt;
      ...
      &lt;dependency&gt;
          &lt;groupId&gt;org.apache.maven.plugins&lt;/groupId&gt;
          &lt;artifactId&gt;maven-source-plugin&lt;/artifactId&gt;
          &lt;version&gt;2.4&lt;/version&gt;
      &lt;/dependency&gt;
  &lt;/dependencies&gt;
  </code></pre>
  
  <p>but it did not correct the problem. I also tried to add the dependency at the call of the plugin :</p>
  
  <pre><code> &lt;plugin&gt;
      &lt;artifactId&gt;maven-source-plugin&lt;/artifactId&gt;
      &lt;version&gt;2.4&lt;/version&gt;
      &lt;executions&gt;
         &lt;execution&gt;
             &lt;id&gt;attach-sources&lt;/id&gt;
             &lt;goals&gt;
                &lt;goal&gt;jar&lt;/goal&gt;
             &lt;/goals&gt;
         &lt;/execution&gt;
        &lt;/executions&gt;
        &lt;dependencies&gt;
            &lt;dependency&gt;
                &lt;groupId&gt;org.apache.maven.plugins&lt;/groupId&gt;
                &lt;artifactId&gt;maven-source-plugin&lt;/artifactId&gt;
                &lt;version&gt;2.4&lt;/version&gt;
            &lt;/dependency&gt;
       &lt;/dependencies&gt;
   &lt;/plugin&gt;
  </code></pre>
  
  <p>but it did not work either</p>