A MIDlet is a Java class that forms the interface between the application and the operating system in a MIDP device. The MIDP platform provides a basic, do-nothing MIDlet class javax.microedition.midlet.MIDlet. Application developers extend this class, overriding the appropriate base-class methods. A J2ME application must include at least one MIDlet, in addition to any supporting classes the application needs. All are packaged into a JAR file for distribution.