title: Adding list item to JList from another JList
body: <p>I have the following code working </p>
  
  <p><code>made_list.setListData(original_list.getSelectedValues());</code></p>
  
  <p>here made_list is one JList and original_list is another JList. If i run with this code the selected value from original_list is replacing the previous value in made_list. I dont want that. i want to append instead.. How do i do this ??</p>