to make Applet or application layout easier, you break a frame up into regions and compose each of them
separately. Each region is called a JPanel. You add components in a JPanel
directly to the JPanel, not via a contentPane. Each JLayout can have its own different
LayoutManager. The AWT (Advanced Windowing Toolkit) equivalent of JPanel is
JPanel when you want a container and Canvas when you want
something to draw on.
If your JPanel layouts are mysteriously scrambled, make sure you did an appropriate
JPanels don’t usually have any visible bounding lines, though they can with code
JPanel as Canvas
Here is a how you extend JPanel to create a custom component that you draw on.
Here is a slightly more complex example that does anti-aliasing. It draws an image like this: