The full version string for this binary release of OpenJDK is 9.0.4+11, and the version number if 9.0.4.
Liberica JDK 9
Liberica is a certified, Java SE 9-compliant distribution of OpenJDK 9 which works on Raspberry Pi 2 & 3 (ARMv6 hardfloat). It has the following notable additions:
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JDK and JRE distributions which include Jigsaw feature and a choice of Client VM, Server VM and Minimal VM.
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OpenJFX 9 compiled for Raspberry Pi.
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Device IO API.
Please refer to the Oracle JDK 9 release notes and what’s new for further information on JDK 9 features. This document further outlines the peculiarities of Liberica distribution as compared to Oracle JDK 9 distribution.
Supported configurations
Liberica is tested and certified on Raspberry Pi 2 & 3 running the following OSes:
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Raspbian OS (armhf)
It is also known to work with
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Debian (armhf)
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Ubuntu (armhf)
Liberica JDK 9 and JRE 9 distribution
Liberica JDK 9 and JRE 9 are distributed as .deb and .tar.gz packages. Please select the one which is most appropriate for your purposes.
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Use Liberica JDK 9 if your application requires javac or other tools and services not present in a JRE, or you would like to use jlink to create a trimmed-down version of the Java Runtime for your particular needs.
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Use Liberica JRE 9 for all other purposes.
With the introduction of the Jigsaw feature and Minimal VM it is now possible to create a Runtime that is sufficient to run your application and trim down the size of the Runtime. To generate a Runtime with just the Minimal VM, add --vm=minimal to jlink options.
By default, the Liberica uses Server VM. Server VM and Client VM can be enabled with -server and -client command line options, respectively. In case the deployment requires to minimize the footprint, it may be beneficial to use Minimal VM, which emphasises on a minimal footprint. It has C1 JIT compiler only, Serial GC and no serviceability features. In a JRE it can be enabled in runtime with -minimal command line option.
LibericaFX
Liberica JDK 9 and JRE 9 come with a bundled LibericaFX 9 implementation, which is based on OpenJFX. The following tables lists Java FX modules status of Liberica distribution
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Java FX Graphics - works.
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Java FX Controls - works.
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Java FX Media - does not work.
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Java FX Webkit - does not work.
The following pipelines are known to work: EGL, SW (direct framebuffer) and GTK. By default, Liberica tries to use the accelerated EGL pipeline, which requires the presence of EGL libraries. If they are not found, the implementation falls back to software rendering.
Use the following command line options to specify the rendering pipeline:
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-Dprism.order=sw forces the use of software rendering pipeline.
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-Dprism.order=es2 forces the use of EGL pipeline and hardware acceleration.
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-Djavafx.platform=gtk if you would like to launch a LibericaFX application using Liberica from X11.
Please refer to the following wiki for more information.
Device IO API
Liberica JDK 9 (and JRE 9) comes with a bundled OpenJDK Device I/O (DIO) API implementation module. DIO provides a Java API for accessing Raspberry PI GPIO pins and for communicating with peripheral devices:
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General Purpose Input/Output (GPIO).
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Inter-Integrated Circuit Bus (I2C), Serial Peripheral Interface (SPI).
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Universal Asynchronous Receiver/Transmitter (UART).
Please refer to the following wiki for more information.
Security Baselines
BellSoft Liberica follows the security baselines for Oracle Java SE. Please refer to the Oracle documentation for a list of issues fixed in a given release.
Known Issues
LibericaFX and EGL on Raspbian
As of 2017, the default location of Broadcom libEGL.so and libGLESv2.so has changed in Raspbian OS. If you’d like to leverage hardware EGL acceleration available from Broadcom video drivers in LibericaFX while running a recent Raspbian OS, run the following command:
cd /opt/vc/lib
sudo ln -s libbrcmEGL.so libEGL.so
sudo ln -s libbrcmGLESv2.so libGLESv2.so