title: Checkstyle - Import-Control rule for src-folder
body: <p>How can I create an <a href="http://checkstyle.sourceforge.net/config_imports.html#ImportControl" rel="nofollow">ImportControl</a> module, which disallows the import of some defined classes within several src-folders?
  - The classes are defined in an own project while they are not allowed to be used within productive code, merly in other unit-tests.</p>
  
  <p>Is that even possible? First I defined a module:</p>
  
  
  
  <pre class="lang-xml prettyprint-override"><code>&lt;module name="ImportControl"&gt;
    &lt;property name="severity" value="error"/&gt;
    &lt;property name="file" value="${config_loc}/import_control.xml"/&gt;
  &lt;/module&gt;
  </code></pre>
  
  <p>Now I need a control importer like this:</p>
  
  <pre class="lang-xml prettyprint-override"><code>&lt;!DOCTYPE import-control PUBLIC "-//Puppy Crawl//DTD Import Control 1.1//EN"
      "http://www.puppycrawl.com/dtds/import_control_1_1.dtd"&gt;
  &lt;import-control pkg=toset&gt;
      ...
  &lt;/import-control&gt;
  </code></pre>
  
  <p>My first approach was to set the disallowed tag with the help of a regex, so that selected files can't be imported. The problem is that I can't define the pkg as "src".</p>
  
  <p>Is there a way to handle this problem with just the import-control.xml?</p>