title: JScrollPane (for JTable) fill and grow in MigLayout
body: <p>It is difficult to describe what happens so here is a SSCCE:</p>
  
  <pre><code>public class TableInScrollPaneTest {
  
  
      public static void main(String[] args) {
          SwingUtilities.invokeLater(new Runnable() {
              @Override
              public void run() {
                  new TableInScrollPaneTest();
              }
          });
      }
  
      public TableInScrollPaneTest() {
  
          JFrame frame = new JFrame();
          frame.setSize(300, 300);
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          frame.setLocationRelativeTo(null);
  
          LayoutManager layout;
  
          layout = new MigLayout("wrap 1, fill", "fill, grow", "[fill, grow 1][fill, grow 2]");
          //layout = new GridLayout(2,1);
  
          JPanel panel = new JPanel(layout);
  
  
          JPanel placeHolder = new JPanel();
          JPanel placeHolder2 = new JPanel();
          placeHolder.setBackground(Color.GRAY);
          placeHolder2.setBackground(Color.LIGHT_GRAY);
  
          JTable table = this.createTable();
          JScrollPane tableScrollPane = new JScrollPane(table, 
                  JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, 
                  JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
          //table.setPreferredScrollableViewportSize(new Dimension(5000,200));
  
          panel.add(placeHolder, "");
          panel.add(tableScrollPane, ""); 
          //panel.add(placeHolder2, "");
  
          frame.setContentPane(panel);
          frame.setVisible(true);
      }
  
      private JTable createTable() {
  
          String[] columnNames = "Name 1,Name 2,Name 3,Name 4,Name 5".split(",");
  
          int rows = 30;
          int cols = columnNames.length;
          String[][] data = new String[rows][cols];
  
          for(int i=0; i&lt;rows; i++) {
              for(int j=0; j&lt;cols; j++) {
                  data[i][j] = "R"+i+" C"+j;
              }
          }
          JTable table = new JTable(data, columnNames);
  
          return table;
      }
  
  
  }
  </code></pre>
  
  <p>I want the scrollPane to use all available space when the frame gets resized by the user. But additionally I want another panel (placeHolder) to grow, too. For example the heigth of the frame divided by 3, the placeHolder gets 1 part and the scrollPane gets 2 parts. The GridLayout is kinda doing what I need, but I'm looking for a solution with MigLayout.</p>
  
  <p>If you uncomment <code>panel.add(placeHolder2, "");</code> and comment the line above it works.</p>
  
  <hr>
  
  <p>EDIT1:<br>
  I tried using the sizegroup contraint. Now the placeHolder and the scrollPane have the same size, but I want the scrollPane take twice as much space. (Additionally in my programm I dont have a placeholder like this, but rather there are some labels, checkboxes and textfields. So sizegroup probably is not what I need except there are more ways to use it)</p>