I use TestComplete with swing quite successfully. There are a couple custom controls that I couldn't get it to pick up, but it was flexible enough to let me write some code that worked well as a workaround.
I know many teams that have had success with Robot Framework  and SwingLibrary . The former is an open source automation framework, and the latter is a test library that can be used with it to test Swing applications. SwingLibrary uses Jemmy, another open source tool, internally. For more open source tools see .