title: JComboBox: want first entry to be blank entry
body: <p>I have a jcombobox which values come from a list. I want to first value to be blank from dropdown list. The way I approached it was by putting new object of the list type in first as example shows :</p>
  
  <pre><code> final List&lt;Object&gt; list = getObjectsList();
    list.add(new Object()); 
  </code></pre>
  
  <p>But this results in null pointer and if do </p>
  
  <pre><code>list.add(null);
  </code></pre>
  
  <p>this solves the issue but then gives me another prob elsewhere with a Comparator method. So any work a rounds would be great thanks.</p>