System dumps, often known as core dumps, are platform-specific and contain a raw binary dump of the process memory. This type of dump has a complete copy of the Java heap, including the contents of all Java objects in the application.
If you want to use MAT to analyze your system dump, you must install the Diagnostic Tool Framework for Java (DTFJ) plugin in the Eclipse IDE. Select the following menu items:
Help > Install New Software > Work with "IBM Diagnostic Tool Framework for Java" > IBM Monitoring and Diagnostic Tools > Diagnostic Tool Framework for Java