MaintainJ is a plug-in for Eclipse, that generates UML sequences in runtime and class diagrams for a given case. This way, it helps the user to be able to understand a very complicated Java or J2EE application quickly and without effort.MaintainJ uses the trace file to render and obtain from it class and sequential diagrams. MaintainJ becomes very useful, for example, when:* You want to know what exactly happened in your application when it ran in a particular case.* You need to understand complicated and large-sized Java applications quickly.* You want to reduce the maintenance costs of an application by more than 20%.In summary a tool that is placed at the vanguard of inverse engineering applications.