<p>Is there any Java library that supports hierarchical column?</p>

<p>For example (the first three row are columns) :</p>

<pre><code>------------------------------------------------
2008                                           |
------------------------------------------------
January               | February               |
------------------------------------------------
Week1 | Week2 | Week3 | Week 1 | Week2 | Week3 |
------------------------------------------------
10    | 20    | 14    | 12     | 15    | 3     |
------------------------------------------------
</code></pre>

May be a
JXTree
from
SwingLab
could approach what you are looking for.
Illustration
here
, from the
Swingx
project
http://avatar21.superihost.com/images/JXTableJXTreeTable.png