ClassLoader and Dependency Charts

[Rakesh Midha <mi...@gmail.com>]

Hello

Looking into the classloader problems and knowing which classsloader loaded
which class has always been a big problem in app servers. Same is the case
with dependencies in Geronimo, We spend lot of time in knowing which
components has what dependencies.

I think it would be nice if in our Web Console we can have a page for
showing Dependency chart and classloader chart.

What do you say? Do you think we should do it for 1.2 or even additional
feature to 1.1

Thanks
Rakesh

Re: ClassLoader and Dependency Charts

[Erin Mulder <me...@alumni.princeton.edu>]

Aaron Mulder wrote:
> http://people.apache.org/~ammulder/classloaders.png
> 
> However, I'm not sure how useful it will be -- it'll show you
> dependencies at the class loader level, but it won't tell you which
> class loaders hold a particular class or which class loader you're
> actually getting at some point when an error is uncovered.

Also, it still needs arrows. :)

Right now, the code for that graph produces SVG.  It would be great to
make it interactive so that you could drag the nodes around, click on a
node to load a div that shows which classes are loaded in it, and maybe
even collapse certain branches.  At JavaOne, I got a few simple
JavaScript behaviors working with the graph prototype, but I'm not sure
how complex it would be to add full-out drag and drop.

Perhaps you can throw the code into the sandbox so other people can
check it out and build on it?  If I recall correctly, I was careful to
make sure that all of its dependencies have Apache-compatible licenses,
(which was actually quite difficult).

Alternatively, someone could create and share a non-ASF-hosted plugin
that makes use of one of the many LGPL graph libraries out there.

Cheers,
Erin

Re: ClassLoader and Dependency Charts

[Aaron Mulder <am...@alumni.princeton.edu>]

We have some code to show a dependency graph kicking around...  We
could probably squeeze that into a portlet.  Here's an example:

http://people.apache.org/~ammulder/classloaders.png

However, I'm not sure how useful it will be -- it'll show you
dependencies at the class loader level, but it won't tell you which
class loaders hold a particular class or which class loader you're
actually getting at some point when an error is uncovered.

Can you think of some way to make it more useful that way?

Thanks,
    Aaron

On 7/19/06, Rakesh Midha <mi...@gmail.com> wrote:
> Hello
>
> Looking into the classloader problems and knowing which classsloader loaded
> which class has always been a big problem in app servers. Same is the case
> with dependencies in Geronimo, We spend lot of time in knowing which
> components has what dependencies.
>
> I think it would be nice if in our Web Console we can have a page for
> showing Dependency chart and classloader chart.
>
> What do you say? Do you think we should do it for 1.2 or even additional
> feature to 1.1
>
> Thanks
> Rakesh
>