Thanks for the tip on CodedInputStream Evan!   I will explore it and
if I get anything out of it will report back my findings for anyone
else dealing with this issue.

On Thu, Jan 20, 2011 at 6:27 PM, Evan Jones <> wrote:
> On Jan 20, 2011, at 2:48 , julius-schorzman wrote:
>> My question is -- can anything be done to retrieve part of the file?
>> It would be nice to know at which point in the file the problematic
>> message occurred, and then I could crop to that point or do some
>> manual exception -- but unfortunately this exception is very general.
>> I find it hard to believe that a single mis-saved bit makes the whole
>> file worthless.
> You are correct: your entire data is not worthless, but at the point of the
> error, you will need some manual intervention to figure out what is going
> on.
> It is probably possible to figure out the byte offset where this error
> occurs. The CodedInputStream tracks some sort of bytesRead counter, I seem
> to recall. However, this will require you to modify the source.
>> I also find it curious that the source provides no way (that I can
>> tell) to get at any lower level data in the p.b. since whenever I try
>> to do anything with it it throws an exception.  Best I can tell I will
>> have to write from scratch my own code to decode the p.b. file.
> The lowest level tools that are provided is CodedInputStream. But yes, you
> will effectively have to "parse" the message yourself. Look at the code that
> is generated for the mergeFrom method of your message to get an idea for how
> it works, and you can read the encoding documentation:
> You can definitely figure out what is going on, but it will be a bit of a
> pain. Good luck,
> Evan Jones
> --

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