title: JSplitPane not filling panel
body: <p>I am having some trouble with making a <code>JSplitPane</code> work how I would like it too.</p>
  
  <p>First, I would like it to fill its container (a JFrame) fully, not have its size determined by the components inside the the split panes. Second, when I resize the container, it does not display the scroll bar on either the <code>JScrollPane</code>s or the <code>JList</code>s.</p>
  
  <p>Any ideas how to make this happen. I'm sure I just need to wire up some listeners correctly, but I'm not quite sure where to start.</p>
  
  <p>My panel looks something like this...</p>
  
  <pre><code>public class MainPanel extends JPanel {
      public MainPanel(){
          JPanel p1 = new JPanel();
          JPanel p2 = new JPanel();
          JPanel p3 = new JPanel();
  
          p1.setLayout(new BoxLayout(p1, BoxLayout.PAGE_AXIS));
          p2.setLayout(new BoxLayout(p2, BoxLayout.PAGE_AXIS));
          p3.setLayout(new BoxLayout(p3, BoxLayout.PAGE_AXIS));
  
          p1.add(new SomeButtons());
          p2.add(new SomeButtons());
          p3.add(new SomeButtons());
  
          p1.add(newNeedyList());
          p2.add(newNeedyList());
          p3.add(newNeedyList());
  
          Dimension ms = new Dimension(0,0);
  
          p1.setMinimumSize(ms);
          p2.setMinimumSize(ms);
          p3.setMinimumSize(ms);
  
          p1.setBackground(Color.red);
          p2.setBackground(Color.green);
          p3.setBackground(Color.blue);
  
  
  
          JScrollPane scp1 = new JScrollPane(p1);
          JScrollPane scp2 = new JScrollPane(p2);
          JScrollPane scp3 = new JScrollPane(p3);
  
          scp1.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_NEVER);
          scp2.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_NEVER);
          scp3.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_NEVER);
  
          scp1.setHorizontalScrollBarPolicy(
             JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
          scp2.setHorizontalScrollBarPolicy(
             JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
          scp3.setHorizontalScrollBarPolicy(
             JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
  
  
          JSplitPane sp1 = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT,scp2,scp3);
          JSplitPane sp2 = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT,scp1,sp1);
  
  
          sp1.setDividerLocation(0.5);
          sp2.setDividerLocation(0.333333333);
  
          sp2.setResizeWeight(0.333333333);
          sp1.setResizeWeight(1.0);
  
          this.add(sp2, BorderLayout.CENTER);
  
      }
  
      /** Some buttons... this part is just to fill the
       panel roughly how I want it look */
  
      private class SomeButtons extends JPanel{
          public SomeButtons(){
              this.setLayout(new BoxLayout(this, BoxLayout.LINE_AXIS));
              this.add(new JLabel("Stuff:"));
              for(int i=0; i&lt;5; i++){
                  final JButton btn = new JButton(" "+i+" ");
                  btn.addActionListener(new ActionListener(){
  
                      @Override
                      public void actionPerformed(ActionEvent ae) {
                          JOptionPane.showMessageDialog(btn,
                                  "Feck off!", "You have pressed a button",
                                  JOptionPane.WARNING_MESSAGE);
                      }
                  });
                  this.add(btn);
  
              }
          }
      }
  
      private JList newNeedyList(){
          String[] s = new String[7];
          s[0] = "Choose Me!";
          for (int i=1; i&lt;7; i++){
              s[i] = "No! Choose ME!";
          }
          return new JList(s);
      }
  }
  </code></pre>
  
  <p>at the moment I have it in a JFrame</p>
  
  <pre><code>public class ThreePanelsTest {
      public static void main(String[] args) {
          JFrame frame = new JFrame();
  
          MainPanel panel = new MainPanel();
  
          frame.add(panel);
  
          frame.setSize(1000,600);
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  
          frame.setVisible(true);
  
      }
  }
  </code></pre>