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 (C, C++), specifically per JEP 191
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 (see below)
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
panama-dev — the usual developer list
panama-spec-experts — moderated, restricted to specification discussions only
Bloggers
Charles Nutter
John Rose
Links
Panama bindings/jextract tutorial
design document: State of the Isthmus
new project CFV for Panama
JEP 191: Foreign Function Interface
JNR example code: Java Native Runtime
early problem space overview: the isthmus in the VM
Repository organization
Project Panama is designed to incubate a series of components for eventual inclusion in the JDK, via curated merge. Following the experience of Project Amber, and Project Valhalla, we have our sanbox-like repository, whose default branch is kept in sync with jdk/jdk, and where each experimental feature is developed in its own branch.
Here’s a list of the branches under active development:
foreign, this branch provides a native binder which greatly reduces the impedence mismatch between native libraries and the JVM;
foreign-memaccess, this branch adds support for foreign memory access;
vectorIntrinsics, this branch adds vectorization support in Java through JVM intriniscs.
When first cloning the panama repository, it is necessary to update it to the desired experimental branch; this can be achieved using the hg update ${branch} command.
For an up-to-date list of the available branches, you might also want to run the hg branches command. For more information regarding each branch, please refer to the README.${branch} file in that branch (if that file does not exist, usual OpenJDK build instruction apply).
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).
Repository workflow
The repository will be managed as follows (note, this process is local and subject to change):
No changes will be pushed to the default branch of the Panama repository. This branch should in fact always be in sync with the upstream repository (jdk/jdk) to facilitate automatic integration of upstream changes, as well as to allow developers to generate diffs against upstream in an easy and predictable fashion (see below).
Create and update JIRA issues to informally describe chunks of work, using repo-panama as the value of the Fix Version field. Additionally, labels are used to identify the branch to which the issue refers to, as shown here;
Commit rough changesets to JDK and/or JVM code, with ad hoc review, change set format, and testing. A typical example of review process for Panama changesets can be found here
Automated infrastructure will take care of performing regular test runs when new changes are pushed to any of the Panama branches; additionally, the infrastructure might automatically propagate changesets from the default branch to other experimental branches (not all branches might opt in on this feature given the subtlety of some of the changes involved).
Infrequently, create a “curated” change set targeted at the upstream JDK repository; properly review, test, integrate. For an example of how this integration process might work, see here. Developers can easily generate a diff against upstream using the hg diff --rev default command from any experimental branch.
OpenJDK logo
Workshop
OpenJDK FAQ
Installing
Contributing
Sponsoring
Developers’ Guide
Vulnerabilities
Mailing lists
IRC · Wiki
Bylaws · Census
Legal
JEP Process
Source code
Mercurial
Bundles (6)
Groups
(overview)
2D Graphics
Adoption
AWT
Build
Compatibility & Specification Review
Compiler
Conformance
Core Libraries
Governing Board
HotSpot
IDE Tooling & Support
Internationalization
JMX
Members
Networking
Porters
Quality
Security
Serviceability
Sound
Swing
Vulnerability
Web
Projects
(overview)
Amber
Annotations Pipeline 2.0
Audio Engine
Build Infrastructure
Caciocavallo
Closures
Code Tools
Coin
Common VM Interface
Compiler Grammar
Detroit
Device I/O
Duke
Font Scaler
Framebuffer Toolkit
Graal
Graphics Rasterizer
HarfBuzz Integration
IcedTea
JDK 6
JDK 7
JDK 7 Updates
JDK 8
JDK 8 Updates
JDK 9
JDK (… 13, 14, 15)
JDK Updates
JavaDoc.Next
Jigsaw
Kona
Kulla
Lambda
Lanai
Locale Enhancement
Loom
Memory Model Update
Metropolis
Mission Control
Mobile
Modules
Multi-Language VM
Nashorn
New I/O
OpenJFX
Panama
Penrose
Port: AArch32
Port: AArch64
Port: BSD
Port: Haiku
Port: Mac OS X
Port: MIPS
Port: PowerPC/AIX
Port: s390x
Portola
SCTP
Skara
Shenandoah
Sumatra
ThreeTen
Tiered Attribution
Tsan
Type Annotations
XRender Pipeline
Valhalla
Verona
VisualVM
Zero
ZGC
Tools
Java SE
Mercurial
jtreg harness
Related
java.sun.com
Java Community Process
JDK GA/EA Builds
Oracle logo
© 2020 Oracle Corporation and/or its affiliates
Terms of Use · License: GPLv2 · Privacy · Trademarks