native-common/README.md

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# datafusion-jni-common

Shared JNI plumbing for the [Apache DataFusion Java](https://github.com/apache/datafusion-java)
native crates. It holds the pieces every DataFusion-backed `cdylib` loaded into a
JVM needs, factored out so they live in one place.

## Linking model

Each consuming `cdylib` statically links its own copy of this crate, so the
runtime singleton is per-library, not per-process. Nothing here is exported with
`#[no_mangle]`, so linking it into several `cdylib`s loaded in one JVM cannot
collide.

## Status

This crate is an implementation detail of Apache DataFusion Java. Its API may
change between releases to track the needs of the native crates that depend on
it.