RoboVM
· The RoboVM compiler translates Java bytecode into native ARM or x86 code. Apps run directly on the CPU.
No interpreter or virtual machine involved.
Download JD-GUI to open JAR file and explore Java source code file (.class .java)
Click menu "File → Open File..." or just drag-and-drop the JAR file in the JD-GUI window robovm-parent-1.14.0.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.