JGoodies FormLayout - put the FormLayout into debug mode

To put the JGoodies FormLayout into debug mode, when you're creating a builder, instead of doing this:

PanelBuilder builder = new PanelBuilder(layout);

add in a FormDebugPanel, like this:

// debug mode
PanelBuilder builder = new PanelBuilder(layout, new FormDebugPanel());

This enables what I think is a terrific debug feature, showing red lines around whatever grid structure you've created. (Sorry I don't have an image out here for this tutorial, but it really is a terrific GUI debugging feature.)