title: How to have JComboBox drop down list which is wider than the JComboBox itself
body: <p>By referring to the answer at <a href="https://stackoverflow.com/questions/3792606/multi-columns-combo-box-for-swing">Multi Columns Combo Box for Swing</a>, I manage to implement a 3 multi columns JComboBox as follow.</p>
  
  <p><img src="https://i.stack.imgur.com/4XCs6.png" alt="alt text"></p>
  
  <p>However, this is not perfect. My intention is to have something without the horizontal scroll bar, as follow.
  <img src="https://i.stack.imgur.com/gMBSp.png" alt="alt text"></p>
  
  <p>My question is, how can I have a JComboBox drop down list, which is wider than the JComboBox itself? I just want to get rid of the horizontal scroll bar. Yet, able to fit in 3 columns into a single list.</p>
  
  <p>The source code are <a href="http://jstock.cvs.sourceforge.net/viewvc/jstock/jstock/src/org/yccheok/jstock/gui/ResultSetCellRenderer.java?view=markup&amp;sortby=date" rel="nofollow noreferrer">ResultSetCellRenderer</a> and <a href="http://jstock.cvs.sourceforge.net/viewvc/jstock/jstock/src/org/yccheok/jstock/gui/AjaxAutoCompleteJComboBox.java?view=markup&amp;sortby=date" rel="nofollow noreferrer">AjaxAutoCompleteJComboBox</a></p>