BlueJ is an integrated Java development environment
EditByBSEditor: BlueJ is an integrated Java development environment developed specifically for introductory programming learning and teaching. It is ideal for small-scale development. BlueJ offers a very easy-to-use and highly interactive interface that allows the interactive creation and invocation of objects.

BlueJ supports:
fully integrated environment
graphical class structure display
graphical and textual editing
built-in editor, compiler, virtual machine, debugger, etc.
easy-to-use interface, ideal for beginners
interactive object creatio
interactive object calls
interactive testing
incremental application development you can free download BlueJ for Liunx 2.5.0 now.