Random Developer Tool Set Written in Java

Had a thought today of writing my own little developer tool set in java (GUI), for things I seem to either want randomly or use excessively on the job (that I believe could be processes sped up).

Some of the components I would like to include would be a MySQL insert tool such .
The only difference would be that it looks much more like a translate application including one box at the top, a button, then another box at the bottom with the output. It may also support update statements also. The key benefit of course would be that its local as opposed to the web version.
Another fun tool would be a simple colour creator, with maybe some sliders and some RGB values. I want this because I sometimes just think "wow I wonder what that mix would create".
The third tool would be a simple code runner, most likely just javascript to start with (considering its what I needed at the time, and I found there was a Java library), but possibly more in the future (can you run java in java?).