Layout Managers
GridBagLayout
usually creates code repetition, which needs additional effort to reduce or eliminate.
As an alternative, you may consider the excellent JGoodies Forms tool.
It takes the interesting approach of defining a small mini-language for defining its layouts (an example of a Domain Specific Language).
While at first somewhat cryptic, this mini-language is quite effective in practice.
The end result is almost always pleasing to the eye.
Another nice feature is its debug mode, whereby a colored grid is laid over the form, so you may easily verify the x-y coordinates of its cells.