Release notes for the jdb debugger

As a demonstration of the JDI, we are providing source code for the jdb debugger, re-written to use the JDI. It contains a few features not found in the standard jdb, including some expression evaluation, but some features of the standard jdb have not been implemented.

jdb man pages

jdb man pages for Windows
jdb man pages for Solaris

Invoking jdb

The jdb sample can be run by executing:

   jdb <options>.. <class-name>

where <class-name> is the name you would normally place on the java command line. The -help option provides information on options.

On Windows platforms the executable bin/jdb.exe, finds the Java Runtime Environment through the Windows registry. If you installed the 1.2 J2SDK or JRE with the standard installation program, this value should be set correctly for you. If not, you'll need to create/edit the registry entry at HKEY_LOCAL_MACHINE/SOFTWARE/JavaSoft/Java Runtime Environment/1.2/JavaHome containing the name of your JRE directory.

On Solaris platforms the executable bin/jdb, finds the Java Runtime Environment through the PATH. The JRE corresponding to the first instance of "java" on the path is the one used.

In addition, jdb can be started by running the 1.2 java VM interpreter of your choice with the class com.sun.tools.example.debug.tty.TTY. Make sure that the jpda.jar file is on the classpath.

For more information on invoking and connecting see Connection and Invocation Details, particularly the section on jdb.

Source for jdb

Full source code for jdb is included in examples/examples.jar. Note: this also includes the source for javadt. Source code of these example application is included to provide concrete examples for debugger developers. Example code may be used, modified and redistributed by debugger developers providing they adhere to the terms in the copyright notice.

Code for jdb is in the directories:

Application code: src/share/classes/com/sun/tools/example/debug/tty
Expression processing code: src/share/classes/com/sun/tools/example/debug/expr

Building jdb

To completely rebuild the jdb classes from the provided source files in examples/examples.jar, you need only to compile them. No special options are required, aside from those which set your classpath to include the com.sun.jdi library found in lib/jpda.jar. However, if want to modify the expression parser in the file Expr.jj, you will need the JavaCC parser generator version 0.7.1. It is available free from SunTest.