Hidden in the SWT javadoc (for DropTargetListener) we do mention this too.
* <p>NOTE: At this point the <code>data</code> field is null. On some
platforms, it is possible
* to obtain the data being transferred before the transfer occurs but in
most platforms this is
* not possible. On those platforms where the data is available, the
application can access the
* data as follows:</p>