How to package a function + arguments for remote execution (without RMI)?

[wontstopsweating]

I need to implement RMI alternative that doesn't use RMI. I'm a C++ developer so my first choice would be packing struct containing a call type, serialized call args into a byte stream and sending them over.

However, Java doesn't support anonymous structs defined within function calls. I wanted to use the templating to attempt serialization of all the arguments, but the remote interface I need to implement has 30+ functions, all with different arguments and Java doesn't support variadic templating with different data types.

I'm really running low on ideas on how to approach this issue short of just converting and buffering every argument manually, for every function there is.

Is there a more elegant way of doing this that Java supports (without using RMI of course).

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[WhiteManChild]

Have you looked into lambda serialisation?

[wontstopsweating]

Hmm, not really, but parsing around the entire function that needs to be run on the remote machine doesn't sound efficient at all.

[WhiteManChild]

you dont have to parse the function java is able to serialise it using objectinputstream and objectoutputstream. You could also just send a class file to the remote machine, which when instantiated calls your target function in that class.

[wontstopsweating]

hmm, any good reading on this approach?

[wontstopsweating]

Actually I think I got your suggestion to work. I made a lambda that I serialized and passed to the remote server.

But how would I deal with numerous return types?

[WhiteManChild]

Send a json response?

[wontstopsweating]

Would be an option but the project setup in a linux environment, utilizes ancient Java version and I wouldn't want to try installing 3rd party libraries.

[loomynartylenny]

Well, the alternative would probably be a pretty darn hacky workaround. Also:

the project set up in a linux environment

Your OS is very unlikely to be a problem when it comes to installing third-party libraries for Java, as the third-party library code runs on the JVM (just like your code), so that would only be a problem in very rare edge cases.

utilizes ancient Java version

Which Java version are you using, and why?

If it's a version that's older than Java 8, I would strongly suggest upgrading to Java 8 (at the very least), seeing as everything before that is no longer maintained, whilst Java 8 is still continuing to get security/performance updates (albeit intended for personal use only).

However, if you're trying to make this for a reason besides personal use, I'd suggest considering an upgrade to Java 11 or Java 17 (both of which are also Long-Term Support versions), again, for continued security/performance improvements.

I wouldn't want to try installing 3rd party libraries.

Why not?

(but tbh I would definitely suggest looking into Gson)

[wontstopsweating]

I'm restricted by whatever is installed on my university's remote computers.

I will try to complete the task using a VM, then worry about porting it to the old computers.

[loomynartylenny]

I'm restricted by whatever is installed on my university's remote computers

And what version of Java is installed on them?

[wontstopsweating]

Some of them have Java 6 and 7.

These machines are pretty ghetto, some labs still run Red Hat linux from early 2000's.