title: How to 'walk' multiple directories, with multiple file extensions, in java?
body: <p>Here is my actual code, which works perfectly :<br>
  String sHomeDir is my only folder where to start the scan<br>
  String sExt is the only extension to search for</p>
  
  <pre><code>try (Stream&lt;Path&gt; walk = Files.walk(Paths.get(sHomeDir)))
  {
      List&lt;String&gt; result = walk.map(x -&gt; x.toString())
          .filter(f -&gt; f.endsWith(sExt)).collect(Collectors.toList());
      ...
  } catch (IOException e) {
     e.printStackTrace();
  }
  </code></pre>
  
  <p>Is it possible to rewrite that, in order to use :<br>
  - Multiple folders to scan (with subtree)<br>
  - Multiple file extensions to search for</p>