Substrate Java RPC Client

There’s some community demand for the substrate RPC java tooling and sdk Posts containing 'java' - Substrate and Polkadot Stack Exchange

Java is still one of the most professionally used languages, mostly by enterprises Stack Overflow Developer Survey 2023.
I have worked at a few major fintechs in India, where Java is hugely prevalant.

Previous attempts but with no longer support and maintenance

I have forked GitHub - splix/polkaj: Library to access and build for Polkadot using Java and started working on a new java substrate API client with ease of use like polkadot-js and aws-java-sdk. It’s a mammoth task getting near to the levels of polkadot-js, but I believe something like this is a must have for the community to support full integration of the APIs compatible with all languages(Go, Rust, Python, Js are well maintained).


I created the Substrate .NET API, and the according toolchain to build an extension from the nodes metadata. It should be quite easy to build the Java API, following the model-driven paradigm, if you want I can support or help with doing it. Let me know. Telegram @darkfriend77

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do you already have something that people can use?

polkaj works to some extent for basic functionalities, I had forked and made some minor changes to run the examples with Java 13.

I am working on a new version, will update here.


thanks! Did you have a chance to update MetadataReader to support v14? I’m stuck on that

apart from Java, what other languages do you think there should be extensive API support for?

not sure. Current languages which are supported

  • rust(subxt)
  • go(centrifuge)
  • python
  • dart
  • js/ts(polkadot js APi)

work in progress.
Plan to release the upgraded library version by July end.

Thanks for this initiative, the more diverse implementations we have around this, the better.

My suggestion is to focus the new work around the new JSON RCP interface since the ecosystem is still lacking of implementations using it (at the moment only Polkadot-API, TS based, aims to fill this gap.

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