Re: Replacing reflection with gnu.bytecode

[Per Bothner <per at bothner dot com>]

Stuart Ballard <sballard@netreach.net> writes:

> Therefore I am considering replacing reflection with gnu.bytecode,
> if it can do what I need it to do.

It can.

> I looked at the API docs of gnu.bytecode but I couldn't figure out the
> equivalents of a lot of these methods, specifically, Field doesn't seem
> to have a getModifiers() method

The version in cvs does.  It was added April 12.  Alternatively, you
can use getFlags(), which is an older method that does the same.

> and I can't find the equivalent of Constructor at all.

A constructor is represented as a method whose name is "<init>".

> I also couldn't
> figure out how to detect a primitive constant, or to get its value.

There is no direct way to do it.  However, the following (untested)
should work:

   ConstantValueAttr attr
     = (ConstantValueAttr) Attribute.get(fld, "ConstantValue");
   if (attr == null)
     not a constant;
   else
     value = attr.getValue(clas.getConstants());

ConstantValueAttr was also added April 12, so you need to use the
cvs version.  Or wait for Kawa 1.6.68, which I hope to have out "soon".

The gnu.bytecode.dump application reads a .class file and prints it
out in human-readable form.  It is useful as example code (as well as
in its own right).
-- 
	--Per Bothner
per@bothner.com   http://www.bothner.com/~per/