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From Andrew McIntyre <mcintyr...@gmail.com>
Subject Re: Any ideas for debugging a byte code generation problem
Date Sun, 20 Mar 2005 03:32:47 GMT
On Sun, 20 Mar 2005 02:25:17 +0000 (UTC), RPost <rp0428@pacbell.net> wrote:
> Couldn't find anything in the JVM spec about a limit on constants
 
The limit is 65535 entries in the constant pool, as the index into the
constant pool is an unsigned short. See:

http://java.sun.com/docs/books/vmspec/2nd-edition/html/ClassFile.doc.html#88659

Not sure if this would help with debugging the problem, but I modified
the Unabstract class that was a part of my jdk142-only compile patch
to dump the constant pool. From the errors in Kathey's original email,
it appears that there may be too few constants in the constant pool
and the indexes for the class info and superclass info in the constant
pool are incorrect (tag 1, UTF8, instead of tag 7, classinfo). If the
constant pool has too few entries, then in the output of
DumpConstantPool, the last few entries in the constant pool will read
"error!". If the constant pool has more entries than the index value,
then the output for the access flags and class info will be obviously
incorrect. If the constant pool actually has the correct number of
entries, then maybe the class info was just written out with bad
indexes.

andrew

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