IBM User Guide for Java V7 on Windows > Troubleshooting and support > Using diagnostic tools

Using the Diagnostic Tool Framework for Java

The Diagnostic Tool Framework for Java™ (DTFJ) is a Java API from IBM used to support the building of Java diagnostics tools. DTFJ works with data from a system dump or a Javadump.

For analysis of core dumps from Linux and AIX platforms, copies of executable files and libraries are required along with the system dump. You must run the jextract utility provided in the SDK to collect these files, see Using jextract. You must run jextract with the same SDK level, on the system that produced the system dump. The jextract utility compresses the dump, executable files, and libraries into a single compressed file for use in subsequent problem diagnosis.

For Java 7 SDKs on Windows and z/OS platforms, you do not need to run the jextract utility. For Java 6 and Java 5.0 SDKs containing versions of the IBM J9 virtual machine before V2.6, you must still run the jextract utility for all platforms.

To work with a Javadump, no additional processing is required.

The DTFJ API helps diagnostics tools access the following information:

• Memory locations stored in the dump (System dumps only)
• Relationships between memory locations and Java internals (System dumps only)
• Java threads running in the JVM
• Native threads held in the dump (System dumps only)
• Java classes and their class loaders that were present
• Java objects that were present in the heap (System dumps only)
• Java monitors and the objects and threads they are associated with
• Details of the workstation on which the dump was produced (System dumps only)
• Details of the Java version that was being used
• The command line that launched the JVM

If your DTFJ application requests information that is not available in the Javadump, the API will return null or throw a DataUnavailable exception. You might need to adapt DTFJ applications written to process system dumps to make them work with Javadumps.

DTFJ is implemented in pure Java and tools written using DTFJ can be cross-platform. Therefore, you can analyze a dump taken from one workstation on another (remote and more convenient) machine. For example, a dump produced on an AIX PPC workstation can be analyzed on a Windows Thinkpad.

API documentation for the DTFJ Interface can be found on developerWorks:

• Java 7 Windows documentation downloads

DTFJ classes are accessible without modification to the class path.

• Using the DTFJ interface
  To create applications that use DTFJ, you must use the DTFJ interface. Implementations of this interface have been written that work with system dumps from IBM SDK for Java versions 1.4.2 and later, and Javadumps from IBM SDK for Java 6 and later.
• DTFJ example application
  This example is a fully working DTFJ application.

Parent: Using diagnostic tools

Error 404 - Not Found

The document you are looking for may have been removed or re-named. Please contact the web site owner for further assistance.