Hi Klaus,
Thank you for offering to contribute to jdb and the OpenJDK project.
Although your suggestion would help to improve jdb, it isn't really
within the current goals for jdb. jdb is primarily used for the following:
* Testing of JDI and JDWP: We have a large number of jdb tests that
are primary maintained to help find JDI and JDWP bugs, not so much
to test jdb itself.
* As example JDI client code for debuggers to use as a reference.
* As a useful platform for reproducing JDI and JDWP bugs. Often IDE
vendors find JDI and JDWP bugs that initially are reproduced with
their own IDE, but they file bugs using jdb as a reproducer. This
provides much simpler reproducer for the serviceability team to work
with.
One things jdb is not meant for is as a production debugging tool. There
are many java IDE's out there that are much better suited for that. We
currently do not wish to spend effort improving the quality of jdb as a
debugger, and instead want to focus on improving jdb where it is useful
the in above 3 use case.
best regard,
Chris
On 10/16/26 11:07 PM, Klaus Wiltgen Klein wrote:
Hello all,
I am interested in doing some work to improve the current state of JDB
in the JDK. My initial idea is rather simple, and if we find it a good
thing, I would be happy to upstream it.
I want to add readline support to JDB. Currently, any bash/EMACS
shortcut, such as CTRL + W or CTRL + A/E, is read as a literal
character. I know we can reuse the existing readline implementation
from jshell, but in order to do that, it's necessary to create a
dedicated module for JDB, rather than keeping its code within jdk.jdi.
In short, my proposal is:
-Create a new module at the root src named jdk.jdb, and move the code
from jdk.jdi/share/classes/com/sun/tools/example/debug/tty/ to
jdk.jdb/share
-Update the imports to match the new location
-Update any existing (broken) script
-Update the src/jdk.internal.le/share/classes/module-info.java file to
contain the newly added module, and start using readline in JDB.
This would provide some of the groundwork needed to improve JDB in
other areas, such as autocomplete for commands, classes, methods, etc.
Let me know if this sounds reasonable or useful to others so we can
discuss it further.
Kind regards
Klaus Klein
