Java source tree (src)
Describes the event management plug-in Java™ source tree.
When you create a plug-in project, it is set up as a Java project with separate folders for source and class files. The source folder is named src. It contains the Java code of the plug-in.
A Java class is also created together with the new plug-in project. This class implements the Java interface for the event or action plug-in, as appropriate. This class must be present in every event or action plug-in.
Follow the Java documentation (Javadocs) of the interfaces as a reference to figure out which method to implement. For logging and tracing in your code, use standard JSR-047 Java Logging APIs.