On 22/10/2019 11:40, Adam Farley8 wrote:
Hey All,
This one goes out to anyone who's struggled to figure out
why OpenJDK isn't loading their class.
The requirement is for OpenJDK to give more detailed
information while loading user-specified classes (e.g. the
one OpenJDK is failing to load). Some debug information is
available while the loading is in-progress, and more is
available after the fact, but it seems there is not a way
to monitor what the ClassLoaders are actually doing without
the use of debugging tools.
For your approval: a formal write-up of the problem (as
I understand it), and a draft webrev containing the
proposed solution.
Tests will be developed and added if/when the issue is
accepted as a problem, and a solution has been selected.
Please review and opine.
This looks very messy and I don't think is in any state to be reviewed.
When changing existing code it is important to respect the existing
coding conventions and keep the style as consistent as possible. Also we
should avoid adding new code in 2019 that uses Vector, StringTokenizer
and other legacy classes.
That said, I think we do need to improve the serviceability and
diagnosability in the java.base module. This will become more important
as more of the runtime is developed in the libraries rather than in
libjvm. We have ad hoc logging in several areas, and one or two places
that emit JFR events, but don't have a consistent approach. Stuart Marks
lead a discussion on this at the OpenJDK workshop in August but it
didn't get any far. Maybe your needs may help that discussion to get
going again.
For the issue at hand, maybe you could start by describing some of the
needs in the class loader areas. Is it mostly visibility issues? I see
the issue you created in JBS mentions "wrong version of a class" which
suggests you are interested in linkage errors too.
-Alan
