× 20th October 2021 We are in the process of creating the October 2021 PSU binaries for Eclipse Temurin 8, 11 and 17.
Track the current status in this issue

Migration Guide

If you are moving from Oracle JDK to OpenJDK from the Adoptium project, you'll probably have a few key questions on your mind. Firstly, you'll want to know what the differences are between Oracle JDK and Adoptium and whether there are any steps you need to take to migrate. The answers to common questions around these choices are covered in the sections that follow.

The following table illustrates the proprietary components that can be found in Oracle JDK 8 and the alternative technologies that are either planned or available to replace them. Click on the links to learn more about each component and any steps that might be necessary to adopt them.

Oracle JDK 8 proprietary component Alternative component OpenJDK 8 OpenJDK 11
Java Web Start IcedTea-Web yes no
JavaFX OpenJFX no no
T2K font rendering engine Freetype yes yes
Monotype Lucida fonts Relicensed Lucida fonts no (coming soon) no (coming soon)
Ductus 2D renderer Pisces/Marlin yes (Pisces) yes (Marlin)
Kodac Color Matching System (KCMS) library LCMS yes yes
SNMP Use JMX (or SNMP4J) yes (not bundled) yes (not bundled)
Sound drivers Use Windows sound drivers yes (not bundled) yes (not bundled)
Java Flight Recorder (JFR) Java Flight Recorder no (coming soon) yes
Java Mission Control (JMC) Use JDK Mission Control no (coming soon) no (coming soon)

Note: JavaFX, JFR, and JMC were all contributed by Oracle to the OpenJDK project for releases after Java 8.

IcedTea-Web

Java Web Start was deprecated by Oracle in Java SE 8 and removed in Java SE 9. IcedTea-Web can provide equivalent functionality for Adoptium 8 users.

IcedTea-Web is available to download from the Iced-Tea Web project page in Linux, Windows, and Portable package formats.

Use IcedTea-Web in the same way as Java Web Start. For more information, see Developing a Java Web Start application and Deploying a Java Web Start application. Whilst IcedTea-Web is written to operate in the same way as Java Web Start there are a few known differences, which are raised as issues in the GitHub project. Work is ongoing to minimize or eliminate these differences.

IcedTea-Web 1.8.x and 2.0.x are compatible with Adoptium 8 builds. We know that software which is based on IcedTea-Web supports the execution of OpenJDK 11 based JNLP applications but IcedTea-Web does not contain any tests to check OpenJDK 11 support and we do not bundle it with Adoptium 11 builds.

OpenJFX

Back in 2017, JavaFX was decoupled from the Oracle JDK and contributed to the OpenJDK community. The OpenJFX community is focused on OpenJFX 11+ and provides binaries that you can use with Adoptium.

OpenJFX 8 is no longer being actively maintained. If you need this capability, we recommend upgrading to OpenJFX 11.

For more information, read the OpenJFX FAQ.

Freetype font rendering library

OpenJDK uses the open source FreeType font rendering library instead of the proprietary T2K font library.

Relicensed Lucida fonts

The Lucida fonts that are available in Oracle JDK 8 have a proprietary 3rd party license. Adoptium intend to provide relicensed Lucida fonts. Work is ongoing to minimize any display issues when these fonts are rendered by Freetype.

Pisces and Marlin

Oracle JDK 8 uses a proprietary 2D graphics renderer called Ductus, whereas OpenJDK uses an open-source renderer called Pisces. From OpenJDK 9, the Marlin renderer is in use. Work is planned at Adoptium to either backport Marlin to OpenJDK 8 and/or minimize any display issues between the two.

LCMS

OpenJDK uses the Little Color Matching System (LCMS) open source open source library instead of the proprietary Kodac CMS library.

JMX

The proprietary SNMP package shipped with Oracle JDK 8 is not present in OpenJDK. Use JMX as an alternative, or SNMP4J. These packages are not bundled with the Adoptium binaries.

Windows sound drivers

Oracle JDK provides native sound drivers for Java 8 on Windows, which are not present in OpenJDK. Use the sound drivers that are available with Microsoft Windows instead.

Java Flight Recorder

Java Flight Recorder (JFR) was decoupled from the Oracle JDK and contributed to the OpenJDK community. Work is underway to backport JFR from OpenJDK 11 to OpenJDK 8. When this work is complete, Adoptium will include JFR in OpenJDK 8 binaries.

JDK Mission Control

Java Mission Control (JMC) is being open sourced under the OpenJDK JDK Mission Control project. JMC builds are available from the JMC Download Page.

Supported Platforms 

Submit an Issue