Read selective fields without deserializing the entire object?
Ashwin Jayaprakash
entire object?
My serialized message is stored in memory as a (Heap)ByteBuffer.
I'm trying to find out if any of the (de-)serialization frameworks
allow a way to read specific fields without having to deserialize the
entire message. The message has almost 200 fields - mostly Strings and
a few long and int fields. Deserialization is expensive and creates
too much garbage considering the fact that I just need to read 1-2
fields.
Thanks in advance.
Henner Zeller
The fields are not 'indexed' in the beginning of the message so that
it is not simple to just jump to a particular field.
What you can do is to direclty use the CodedInputStream to parse
through the message, tag by tag and only read the tags you are
interested in. As soon as you have all fields together, you can stop
reading. So it is a bit manual work involved.
Also, if you want to be faster and skip bigger parts of the message,
make sure to create sub-messages within that message, maybe there is a
logical grouping of your fields ? You can skip a sub-message at once
if you don't need it instead of iterating through all fields in it,
which is faster.
H.
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> Thanks in advance.
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Ashwin Jayaprakash
ZHOU Xiaobo
Can ProtoBuf do in-place deserialization?
Say I have a packet including a COMMAND field and a big DATA field, and
I should only deserialize this packet to read COMMAND to decide how to process DATA.
The question is: does ProtoBuf copy DATA field when deserializing, and can I avoid that?
Kenton Varda
A further question:
Can ProtoBuf do in-place deserialization?