WSO2 Enterprise Integrator - Core Server Feature
· This feature contains the bundles required for Enterprise Integrator Core Service hosting functionality
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 org.wso2.carbon.integrator.server.feature-6.5.0-m3.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.