UPDATE:

(to be more clear)

You can find JRE 8, JRE 9 and JRE 10 on Oracle's official website (click on each). But where is JRE 11?!

Also, JDK 11 doesn't include a JRE. I was expecting JRE to be installed with JDK.

Do final users of our apps need to install JDK?

ORIGINAL version of the question:

I downloaded and installed Oracle JDK 11 from its official site. I installed both ..._linux-x64_bin.rpm and ..._windows-x64_bin.exe (first on a Linux machine and second on a Windows machine). But I saw an unexpected thing! Where is JRE?

This is a snapshot of installation path on CentOS 7. As you can see there is no jre folder:

# ls /usr/java/jdk-11.0.1/ bin conf include jmods legal lib README.html release

Same snapshot about Oracle JDK 8 (See jre folder specially):

# ls /usr/java/jdk1.8.0_191-amd64/ bin lib src.zip COPYRIGHT LICENSE THIRDPARTYLICENSEREADME-JAVAFX.txt include man THIRDPARTYLICENSEREADME.txt javafx-src.zip README.html jre release

Same snapshots on Windows machine:

> dir /b "C:\Program Files\Java\jdk-11.0.1" bin conf COPYRIGHT include jmods legal lib README.html release > dir /b "C:\Program Files\Java\jdk1.8.0_181" bin COPYRIGHT include javafx-src.zip jre lib LICENSE README.html release src.zip THIRDPARTYLICENSEREADME-JAVAFX.txt THIRDPARTYLICENSEREADME.txt

On Windows machine, there are also two another differences between JDK 8 and JDK 11.

  1. A standalone JRE alongside JDK as you can see:

    > dir /b "C:\Program Files\Java" jdk-11.0.1 jdk1.8.0_181 jre1.8.0_181

  2. In path C:\Program Files (x86)\Common Files\Oracle\Java:

    > dir "C:\Program Files (x86)\Common Files\Oracle\Java" ... ... 14 java.settings.cfg ... <JUNCTION> javapath [C:\Program Files (x86)\Common Files\Oracle\Java\javapath_target_3015921] ... <DIR> javapath_target_3015921 ...

    As you see javapath (that is in PATH environment variable) points to javapath_target_3015921. This folder contains 3 executables of JDK 8 (that aren't links!):

    > dir /b "C:\Program Files (x86)\Common Files\Oracle\Java\javapath" java.exe javaw.exe javaws.exe

Finally, I searched the web to find a standalone JRE and found out it doesn't exist!

Do final users of our programs need to install JDK?

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1 Answer

The whole structure with Java 11 has changed. Java is now a modular platform, where you can create your own "JRE" distribution with specifically the modules that you need to run your application.

The release notes at have the following sentence:

In this release, the JRE or Server JRE is no longer offered. Only the JDK is offered. Users can use jlink to create smaller custom runtimes.

Documentation about jlink:

And another article about it:

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