🚀 go-pugleaf

I'm having some difficulty in try to reproduce the UI behavior of a program
I've written in C++ Builder. The main form looks basically like this:

+------------------------------------------------------------+
| File Edit Help                                             |
|------------------------------------------------------------|
|                        |                                   |
|  /------\    /------\  |  Text area                        |
|  |Button|    |Button|  |  This should grow to east and     |
|  \------/    \------/  |  south as window is resized. Its  |
|                        |  left edge is anchored at its     |
|  /------\    /------\  |  designed position. If window is  |
|  |Button|    |Button|  |  resized to be narrower than the  |
|  \------/    \------/  |  text area's left edge, the text  |
|                        |  area should be clipped, as well  |
|  /------\    /------\  |  as any buttons in the left hand  |
|  |Button|    |Button|  |  area of the main form.           |
|  \------/    \------/  |                                   |
|                        |  If the Hide/Show button is       |
|------------------------|  pressed, the text area is        |
|                        |  hidden and resizing the window   |
|  (that's a horizontal  |  simply extends grey form back-   |
|   line above)          |  ground. The status bar of course |
|                        |  is always anchored to the bottom |
|      /---------\       |  and if the window is too small   |
|      |Hide/Show|       |  to fit in the buttons they are   |
|      \---------/       |  clipped.                         |
|                        |                                   |
|------------------------------------------------------------|
| Status bar                                                 |
+------------------------------------------------------------+

This was trivial to set up in C++ Builder but I've been unable to come up
with a way to duplicate this behavior in Java. If anyone can offer some
advice, it would be appreciated.