title: Maven Force Update Snapshot Dependencies
body: <p>Here is the result of mvn -version:</p>
  
  <pre><code>Apache Maven 3.0.4 (r1232337; 2012-01-17 00:44:56-0800)
  Maven home: /usr/share/maven
  Java version: 1.7.0_67, vendor: Oracle Corporation
  Java home: /Library/Java/JavaVirtualMachines/jdk1.7.0_67.jdk/Contents/Home/jre
  Default locale: en_US, platform encoding: UTF-8
  OS name: "mac os x", version: "10.8.5", arch: "x86_64", family: "mac"
  </code></pre>
  
  <p>Suppose I have a snapshot dependency:</p>
  
  <pre><code>&lt;dependency&gt;
      &lt;groupId&gt;org.puzzled&lt;/groupId&gt;
      &lt;artifactId&gt;foo&lt;/artifactId&gt;
      &lt;version&gt;1.0.4-SNAPSHOT&lt;/version&gt;
  &lt;/dependency&gt;
  </code></pre>
  
  <p>I have a downloaded copy of that snapshot in my local repo. But then other developers have made improvements and there is an update to the foo-1.0.4-SNAPSHOT.jar. I want to issue Maven an executive order to update that dependency by downloading it from a remote repository.</p>
  
  <p>According to the response to <a href="https://stackoverflow.com/questions/4701532/force-maven-update">this</a> and many other questions on SO, if I do</p>
  
  <pre><code>mvn clean -U package
  </code></pre>
  
  <p>it should just (re)download all the dependencies. Right? That is not what happens. It downloads metadata for snapshot dependencies, deduces (and wrongly, at that) that no updating is required. I have to delete the associated subdirectory in my local .m2 repository for Maven to update a snapshot release from the remote repo, even with the -U flag.</p>
  
  <p>Is this a bug, or am I missing something?</p>