On 23/11/2011 01:02, Andrzej Bialecki wrote:
On 22/11/2011 19:47, PJ Herring wrote:
Hey Chris,
Thanks for the response. I looked at the documents you sent me, and I
really do think incorporating some kind of DI Framework could be a great
addition to Nutch.
I have a general plan of attack, but I'll try to write that up more
formally and send it out to get some kind of feedback.
This sounds interesting. As Chris mentioned, the current plugin system
is far from ideal, but so far it worked reasonably well. The key
functionality that it implements is:
* self-discovery of services provided by each plugin,
* easy pluggability, by the virtue of dropping "super-jars" (jars with
impl. classes and nested library jars) to a predefined location,
* controlled classloader isolation between plugins so that incompatible
versions of libraries can be used
* but also ability to export specified classes and libraries so that one
plugin can use other plugin's exported resources on its classpath.
* optional auto-loading of dependent plugins
In the past one contributor made a bold attempt to port Nutch to OSGI,
and it turned out to be much more complicated than we expected, and with
a bigger impact on the way Nutch applications were supposed to run ...
so at that time we didn't think this complication was justified.
If we can figure out something between full-blown OSGI and the current
system then that would be great.
You may also want to take a look at JSPF (http://code.google.com/p/jspf)
which perhaps could be made to satisfy the above requirements without
too much refactoring.
--
Best regards,
Andrzej Bialecki <><
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