Java SE considerations

WebSphere® eXtreme Scale requires Java™ SE. In general, newer versions of Java SE have better functionality and performance.

Supported versions

You can use WebSphere eXtreme Scale with Java SE Version 8. The version that you use must be currently supported by the Java Runtime Environment (JRE) vendor. If you want to use Secure Sockets Layer (SSL), you must use an IBM Runtime Environment.

If you are installing WebSphere eXtreme Scale within WebSphere Application Server Version 9, you can use the JRE that is included in the WebSphere Application Server installation. If you are installing WebSphere eXtreme Scale within WebSphere Application Server Version 8.5.5, you must upgrade the WebSphere Application Server SDK to Version 7 or later before installing WebSphere eXtreme Scale.

IBM Semeru Runtime Certified Edition Java 11 and IBM Semeru Runtime Certified Edition Java 17 are supported since WebSphere eXtreme Scale Version 8.6.2.

For more information, see Supported software.

Upgrading the JDK in WebSphere eXtreme Scale

Common questions about the upgrade process for releases of WebSphere eXtreme Scale in both stand-alone and WebSphere Application Server environments follow:

How do I upgrade the JDK that is included with WebSphere eXtreme Scale for WebSphere Application Server?
You need to use the JDK upgrade process that is made available by WebSphere Application Server. For more information, see https://www.ibm.com/support/pages/apar/PM56253.

You can also see Updating the Java SDK.
Which version of the JDK should I use when using WebSphere eXtreme Scale in a WebSphere Application Server environment?
You can use any Java Version 7 or later that is supported by WebSphere Application Server.