Apache MINA
· Apache MINA is a network application framework which helps users develop high performance and highly scalable network applications easily. It provides an abstract event-driven asynchronous API over various transports such as TCP/IP and UDP/IP via Java NIO.
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 build-2.0.0-RC1.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.