Create jre from OpenJDK Windows

Question

We are switching from Oracle JDK/JRE to OpenJDK. Now I found only the JDK but I want to have a JRE as well from OpenJDK. This is for installing our application on the clients without the need of having the full JDK.

Is there a way to create a JRE package from the OpenJDK for Windows X64?

Answer 1

Inspired by the article Using jlink to Build Java Runtimes for non-Modular Applications I used the commands:

1. java --list-modules to get a list of all openjdk modules available
2. jlink --no-header-files --no-man-pages --compress=2 --add-modules <module-list from step 1> --output java-runtime to create a compact jre.

For OpendJDK 12 this is the command I ended up with:

jlink --no-header-files --no-man-pages --compress=2 --add-modules java.base,java.compiler,java.datatransfer,java.desktop,java.instrument,java.logging,java.management,java.management.rmi,java.naming,java.net.http,java.prefs,java.rmi,java.scripting,java.se,java.security.jgss,java.security.sasl,java.smartcardio,java.sql,java.sql.rowset,java.transaction.xa,java.xml,java.xml.crypto,jdk.accessibility,jdk.aot,jdk.attach,jdk.charsets,jdk.compiler,jdk.crypto.cryptoki,jdk.crypto.ec,jdk.crypto.mscapi,jdk.dynalink,jdk.editpad,jdk.hotspot.agent,jdk.httpserver,jdk.internal.ed,jdk.internal.jvmstat,jdk.internal.le,jdk.internal.opt,jdk.internal.vm.ci,jdk.internal.vm.compiler,jdk.internal.vm.compiler.management,jdk.jartool,jdk.javadoc,jdk.jcmd,jdk.jconsole,jdk.jdeps,jdk.jdi,jdk.jdwp.agent,jdk.jfr,jdk.jlink,jdk.jshell,jdk.jsobject,jdk.jstatd,jdk.localedata,jdk.management,jdk.management.agent,jdk.management.jfr,jdk.naming.dns,jdk.naming.rmi,jdk.net,jdk.pack,jdk.rmic,jdk.scripting.nashorn,jdk.scripting.nashorn.shell,jdk.sctp,jdk.security.auth,jdk.security.jgss,jdk.unsupported,jdk.unsupported.desktop,jdk.xml.dom,jdk.zipfs --output java-runtime

Answer 2

As others have mentioned, there's no longer a separate JRE distributed with the JDK since Java 9. You will need to use jlink and specify the modules your code depends on to generate a custom jre.

Because this can be a hassle, I've created a web-based tool to make it easier to create a custom JRE from an OpenJDK implementation (such as Oracle HotSpot, Eclipse OpenJ9, or Amazon Corretto) using jlink. The tool will give you the correct jlink command to run depending on your needs.

I've also included a way to make a standard Java SE JRE for those who just want a basic lightweight (~40-60 MB) JRE. If you know how to use a terminal, it'll take you less than 2 minutes to create a general-use JRE for JDK 9 and up.

Give it a try here - EasyJRE: https://justinmahar.github.io/easyjre/

Answer 3

Amazon Corretto OpenJDK https://aws.amazon.com/corretto/ has the builds for JDK and JRE

Answer 4

So I'm going to post something a little bit easier than what was posted by SteinarH. I didn't want to have to compile that list myself so.... this does it for you. Also for the sense of being a bit more concise I wouldn't label it java-runtime but instead jre-11 (or whatever version you are using).

This is PowerShell:

jlink --no-header-files --no-man-pages --compress=2 --add-modules $($(java --list-modules) -join "," -replace "@[0-9]*") --output jre-11