Do not set the null layout. It is not the "default layout" and is not "the simplest to implement". It is actually very difficult to get right.
JFrame
uses BorderLayout
by default. Add JProgressBar
with BorderLayout.NORTH
, JTextPane
with BorderLayout.SOUTH
and JScrollPane
with BorderLayout.CENTER
. Remove all setBounds
. The components will appear. If you need to position them in some sophisticated way instead, read about GridBagLayout
.