在没有组件

Question

我试图帮助其他用户，我遇到了一个问题，我想用GridBagLayout做这个：

        c1   |                  c2                     |   c3
       ~10%  |                 ~80%                    |  ~10%
             v                                         v   
     |-------------------------------------------------|
 r1  |                       B1                        |  <S1>
~50% |-------------------------------------------------|
---->
             |--------------------------------------------------|
 r2    <S2>  |                      B2                          |
~50%         |--------------------------------------------------|

具体问题是我想将c2的重量设置为80％，但我没有c2 中存在的组件（设置B1或B2的重量不会产生所需的效果，因为它们也分别存在于c1和c3中。

有没有办法指定网格约束没有添加不可见的组件或细分面板？看了Javadoc之后，我猜不到，但我想我还是会为后人发布这个问题。

MCVE：

public class StaggerTest {
  public static void main(String[] args) {
    JFrame frame = new JFrame("Stagger Test");
    frame.setSize(600, 600);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JPanel panel = new JPanel(new GridBagLayout());

    placeComp(new JButton("1"), panel, 0, 0, 2, 1, 0, 0);                  // B1
    placeComp(Box.createHorizontalStrut(10), panel, 2, 0, 1, 1, 0.1, 0.5); // S1
    placeComp(Box.createHorizontalStrut(10), panel, 0, 1, 1, 1, 0.1, 0.5); // S2
    placeComp(new JButton("2"), panel, 1, 1, 2, 1, 0, 0);                  // B2

    // TODO: Is there another way, outside subdividing panel?
    placeComp(Box.createGlue(), panel, 1, 2, 1, 1, 0.8, 0);

    frame.setContentPane(panel);

    frame.setVisible(true);
  }

  public static void placeComp(Component comp, JPanel panel, int x, int y, int w, int h,
      double wx, double wy) {
    GridBagConstraints cons = new GridBagConstraints();
    cons.gridx = x;
    cons.gridy = y;
    cons.gridwidth = w;
    cons.gridheight = h;
    cons.weightx = wx;
    cons.weighty = wy;
    cons.fill = GridBagConstraints.BOTH;
    panel.add(comp, cons);
  }
}