object stream format

[Larry]

Is there any documentation on Java's object stream format or any tools
to display it in a readable format and/or create them?

 

[Thomas Fritsch]

Is there any documentation on Java's object stream format

See http://java.sun.com/j2se/1.4/pdf/serial-spec.pdf (Chapter 6: Object
Serialization Protocol)

 

[Timo Stamm]

Is there any documentation on Java's object stream format
Yes:

http://java.sun.com/j2se/1.5.0/docs/guide/serialization/spec/protocol.html#8101


or any tools to display it in a readable format

Isn't it easier to deserialize in Java and use Reflection and toString()
to print it?

and/or create them?

Simply serialize an object in Java?


Timo

 

[Larry]

Isn't it easier to deserialize in Java and use Reflection and toString()
to print it?



Simply serialize an object in Java?

Yes, if I am using Java. But I want to process the object stream from
another language (Perl).

 

[Timo Stamm]

Yes, if I am using Java. But I want to process the object stream from
another language (Perl).

Sounds like a lot of pain. I would avoid this under all circumstances
and rather use a serialization protocol that is available in both languages.

 

[Thomas Hawtin]

Sounds like a lot of pain. I would avoid this under all circumstances
and rather use a serialization protocol that is available in both
languages.

Or load a JVM from within Perl?

Tom Hawtin

 

[Chris Uppal]

Sounds like a lot of pain. I would avoid this under all circumstances
and rather use a serialization protocol that is available in both
languages.

Especially since the serialisation may involve custom Java code.

I.e. the problem is not solvable in general. Many specific cases can be solved
by this approach, but it's not clear that reducing the problem that far doesn't
also bring other solutions into play. XML ? YAML ?

-- chris

 

[Larry]

Sounds like a lot of pain. I would avoid this under all circumstances
and rather use a serialization protocol that is available in both languages.

I am only in control of the client Perl script. I can't change the
server code. The server code expects to receive a Java object stream
from the client (which is supposed to be an applet).

I already have a bunch of Perl client scripts in place. I don't want
to add a JVM as a dependency just for this one object stream.

I have no pretenses of this solution being part of a cohesive system
architecture. This is a hack for sure. But there is a place for
hacks, imho.

 

[Timo Stamm]

Timo Stamm wrote:
I am only in control of the client Perl script. I can't change the
server code.

I hope you can at least use the source of the server code for debugging.

The server code expects to receive a Java object stream
from the client (which is supposed to be an applet).

Using Java to create the stream seems to be the best option, then. You
simple create the objects and call a method to serialize them to a
stream. It is very straight-forward.

I already have a bunch of Perl client scripts in place. I don't want
to add a JVM as a dependency just for this one object stream.
This is a hack for sure. But there is a place for
hacks, imho.

Sure there is, but be warned that under these circumstances, it's not a
hack, it's a *MAJOR HACK*. I only allow myself to use hacks if they save
me a lot of time.

In your case, you have to options:

a)
- learn some basic java
- have a dependency on a jre in your client

b)
- learn a lot about the java serialization protocol
- setup a testing environment
- have a component in the client that is very difficult to maintain and
extend


I just don't think b) will save you time.


Timo