GridBagLayout: how to fill all empty spaces

Question

I've have a JFrame contains some JPanels using a gridBagLayout (3 rows, one column). That's my code:

Container main_container = getContentPane();
GridBagLayout layout = new GridBagLayout();
main_container.setLayout(layout);
GridBagConstraints c = new GridBagConstraints();

StatoMagazzini jpanel_stato_magazzini = new StatoMagazzini();
c.gridx = 1;
c.gridy = 2;
c.fill = GridBagConstraints.BOTH;
layout.setConstraints(jpanel_stato_magazzini, c);

AcquistoLotto jpanel_acquisto = new AcquistoLotto(i, jpanel_stato_magazzini);
c.gridx = 1;
c.gridy=1;
c.fill = GridBagConstraints.HORIZONTAL;
c.anchor = GridBagConstraints.FIRST_LINE_START;
layout.setConstraints(jpanel_acquisto, c);

ButtonPanel jpanel_button_panel = new ButtonPanel(i);
c.gridx=1;
c.gridy=3;
c.anchor = GridBagConstraints.CENTER;
layout.setConstraints(jpanel_button_panel, c);

main_container.add(jpanel_acquisto);
main_container.add(jpanel_stato_magazzini);
main_container.add(jpanel_button_panel);
pack();

and that's the result (a ugly result): https://docs.google.com/file/d/0Bxi2arJ2Dv9xbEo0Smd5QUN4UGc/edit?usp=sharing

i would eliminate that empty spaces on top and extend the second component (that is a scrollable JTable). How i should modify code?

Answer 1

you could set the layout of the container to BorderLayout (or something equivalent) and create an extra JPanel with the GridBagLayout and add it to the container

because of Borderlayout, the JPanel will take as much space as possible