Manik Surtani wrote:
A nasty bug, spotted by someone in the user forum (initially as a
Copying from the JIRA:
"This is a nasty. What started life as an optimisation for certain types
of objects in a marshalled stream (Fqn, GlobalTransactio, String and
Serializable) has become a major limitation in that a single stream can
only hold up to 32767 different (not equal()) instances of such objects.
Basically the optimisation was, for example, instead of writing "hello"
to a stream twice, just write it once and use a reference for all
subsequent times. Unfortunately this reference was encoded as a short,
hence the limitation of 32767.
Fixing this will definitely break wire compatibility with JBoss Cache
2.0.0, although JBC does allow backward compatibility by specifying
replication version in your configuration, thanks to the
So I guess this mandates the need for a CacheMarshaller210. The
question is how do we fix this. The obvious thing is to replace the
short references with integers. The 2 ^ 31 - 1 number of references
this would allow should be plenty! The drawback though, is larger
streams. 4-byte refs instead of 2-byte refs can be an unnecessary
overhead especially if objects aren't repeated much.
I wouldn't worry too much about the extra bytes. However, you could
maintain backwards compatibility, and save the 2 bytes, by stealing the
sign bit on the short. If byte1 & 0x80 then read 3 more bytes, else read
only 1 more.
Jason T. Greene
JBoss, a division of Red Hat