OpenJDK: Panama

Project Panama: Interconnecting JVM and native code

We are improving and enriching the connections between the Java virtual machine and well-defined but “foreign” (non-Java) APIs, including many interfaces commonly used by C programmers.

To this end, Project Panama will include most or all of these components:

• native function calling from JVM

• native data access from JVM or inside JVM heap

• new data layouts in JVM heap

• native metadata definition for JVM

• header file API extraction tools (jextract)

• native library management APIs

• native-oriented interpreter and runtime “hooks”

• class and method resolution “hooks”

• native-oriented JIT optimizations

• tooling or wrapper interposition for safety

• exploratory work with difficult-to-integrate native libraries

Community

This Project is sponsored by the Hotspot Group.

• Mailing lists & News

panama-dev — Foreign Function & Memory API, Vector API jextract-dev — jextract tool Stay tuned on latest Panama development at Inside.java

• Design documents

Panama foreign memory acccess

Panama foreign function support Panama jextract usage examples early problem space overview: the isthmus in the VM

• JEPs

Foreign Function & Memory API: JEP-424 Vector API: JEP-426

• Talks

Project Panama: say goodbye to JNI! The Vector API in JDK 17 ByteBuffers are dead, long live ByteBuffers! Deconstructing Panama Vector API Panama: a foreign policy for Java

Repository organization

Project Panama is designed to incubate a series of components for eventual inclusion in the JDK, via curated merge. Project Panama features are being actively developed in the following repositories:

• Panama foreign support, which adds support for foreign memory access, as well as for foreign function calls;

• Panama vector support, which adds vectorization support in Java through JVM intriniscs; and

• jextract, a tool which mechanically generate Java bindings from native library headers.

The legacy Panama repository is also available here, although we do not expect to carry out further work there; as such this repository should not be used (and in the future we might make this more explicit by marking the legacy repository as read-only).