Binding Listeners Patch

_From [sberlin](https://code.google.com/u/sberlin/) on June 11, 2009 23:51:20_

Created a separate issue for binding listeners, as it's not necessarily the
same as issue 38 (where the prior patch is at).

This is a framework (modeled after the type listener framework) for adding
arbitrary binding listeners that are notified when a new binding is
available.  The patch also converts eager singleton listeners to using the
framework.  This solves the following issues:

\* JIT eager singleton bindings discovered after Injector creation were not
eagerly created.  (no current issue id for this)
* JIT eager singleton bindings from any child injector were not eagerly
created. ( issue 386 )
* Allows users to develop their own strategies for eager singletons (using
different singleton scopes, for instance). ( issue 38 )

An outstanding issue that Alen pointed (in issue 38 ) is "using a
PrivateModule with expose the exposed binding will get heard 2 times."

**Attachment:** [gist](https://gist.github.com/abeb77b43bbe95c472b2)
   _[binding-listeners.txt](https://gist.githubusercontent.com/gissuebot/abeb77b43bbe95c472b2/raw/f67817562c8251ceec4d170137e4103b1e1fdcc0/binding-listeners.txt)_

_Original issue: http://code.google.com/p/google-guice/issues/detail?id=387_