- Java 8 is recommended for all CICS TS V5.x releases
- Get the APARs PI87181 and PI87695, for the service refresh with CICS
- IBM SDK, Java Technology Edition, Version 7 and Version 7 Release 1 will reach end of service September 2019
IBM SDK, Java™ Technology Edition, Version 8 is now the recommended version for use with all CICS TS V5.x releases. The SDK is used to run all types of Java applications, including OSGi, Liberty, Security Token Service, Axis2, web services validation, the new multi-factor authentication support, as well as offline utilities such as CICS web services and XML assistants.
This SDK is the culmination of the IBM Java, z/OS, and CICS development teams continuously looking for ways to enhance your Java experience on the mainframe.
Over the last few years we have added support for Java 8 to CICS TS V5.x that brought with it some good performance enhancements for Java workloads as outlined in the CICS TS for z/OS V5 Performance Report in Chapter 5. We also added Java EE support to CICS TS V5.3+ that opened up CICS to a whole new set of Java applications, and provided starter guides with the new Redbook Liberty in IBM CICS: Deploying and Managing Java EE Applications and Java video course series.
More recently the IBM SDK, Java Technology Edition, Version 8 service refresh 5 was released in September 2017. It includes still further potential to improve performance and security, reduce the JVMs memory footprint, and take advantage of hardware acceleration on the IBM z13 and z14. A summary is in article Service Refresh 5. To use this service refresh with CICS you will need to apply CICS APARs PI87181 and PI87695.
From what we can tell, many of our customers have already successfully upgraded to Java 8 on z/OS. One such customer, Bankdata, are happy to report in the latest Stepwise Modernization Made with z Systems story…
“The Java upgrade from V7 to V8 took only 10 minutes. The developers very much would like to be at the newest version of the Java compiler. All our new projects are using Java 8, and we haven’t had to change the legacy Java apps.” — Charles Vindum, Systems Architect, Bankdata.
Upcoming end of service for Java 7
IBM SDK, Java Technology Edition, Version 7 and Version 7 Release 1, will continue to be supported until September 2019, as summarized in IBM developer kits lifecycle dates. After that date, fixes (including security issues) will only be provided in Version 8.
Also from September 2019, Liberty with fix pack 220.127.116.11 onwards will only run with Java 8 SDKs – see Removal notices.
The topic Planning gives advice on the considerations and steps to upgrade the IBM SDK. You can install multiple versions of the IBM SDK on z/OS, and then stage the roll-out with CICS, batch and other systems that use Java over time.
Once the runtime systems have been upgraded, Java developers can decide if and when to change development and build systems to use the Java 8 API. CICS Explorer SDK 5.3+ and CICS TS build toolkit 5.3+ both support Java 8.