I was recently asked for some pointers on where to look for helpful resources to get started with writing and running stand-alone Java™ applications on z/OS®. Not running Java in CICS® or IMS. Not in a Liberty Server. Just a plain old Java application (with a main() method!) submitted as a batch job on z/OS. So, I put together the following list of doc sites, Redbooks®, and github links that address the main questions when looking at getting a first Java application on z/OS up and running.

Keep in mind, these questions weren’t coming from someone looking to create a fully automated CI/CD pipeline using the latest tools in support of enterprise DevOps in an integrated hybrid cloud environment. He just wanted to know where to start with Java on z/OS.

Where do I get it? How do I install and use it?

• Java z/OS installation/download site:
  • https://www.ibm.com/support/pages/java-sdk-products-zos

• IBM Java SDK documentation sites:
  • IBM Semeru Runtime Certified Edition for z/OS, Version 11/17/21: https://www.ibm.com/docs/en/semeru-runtime-ce-z
  • IBM® SDK, Java Technology Edition, Version 8: https://www.ibm.com/docs/en/sdk-java-technology/8
    
    

How do I develop Java applications with Eclipse with the intent of running them on z/OS?

• Java Stand-alone Applications on z/OS, Volume I  & II – IBM Redbooks May 2006, Feb 2007 
  (these are older links, but the basics still apply. For example, there’s a section on configuring Eclipse for remote debugging which might look different with current Eclipse tools and SDKs)
  • https://www.redbooks.ibm.com/abstracts/sg247177.html
  • https://www.redbooks.ibm.com/abstracts/sg247291.html

How do I submit Java applications as batch jobs on z/OS and read/write z/OS files (equivalent links exist for v11/17/21)?

• JZOS (Java Batch Launcher and Toolkit for z/OS) Overview:  https://www.ibm.com/docs/en/sdk-java-technology/8?topic=components-jzos-batch-launcher-toolkit

• API Javadoc:  https://www.ibm.com/docs/en/sdk-java-technology/8?topic=components-java-batch-toolkit-zos-jzos

• Installation and User Guide:  https://public.dhe.ibm.com/software/Java/Java80/JZOS/jzos_users_guide_v8.pdf

• Sample programs:  https://public.dhe.ibm.com/software/Java/Java80/JZOS/jzos_samples.zip

Any other gotchas or useful things to know about Java on z/OS?

•  Java on z/OS Hints and Tips github site: https://github.com/IBM/IBM-Z-zOS/tree/main/zOS-Education/Hints-and-Tips-for-Java-on-zOS

IBM Semeru Runtime Certified Edition for z/OS product page - https://www.ibm.com/products/semeru-runtime-certified-zos