Mainframe supports JAVA. You can have a mix of Java and COBOL modules. The Java plays a predominant role in modernizing mainframe applications. You can understand how JCL calls both Java and COBOL programs during batch job execution.
Simple diagram from IBM can explain how Java works
To run Java on mainframe we need Batch launcher utilities
- The BPXBATCH or BPXBATSL utility
- IBM JZOS Batch Toolkit for z/OS (JZOS)
The next modernization is the data transfer between these job steps (Cobol and Java ) can be realized by storing data in temporary data sets or in UNIX System Services files.
Tools for Java Developers to work on ZOs
For Java developers who have never worked on z/OS, the OMVS Shell and the ISHELL might be difficult to handle.
To solve this issue, the z/OS UNIX System Services environment can be enriched with some tools that are very common in the Linux and UNIX space, such as:
- Unix-Why OMVS on Mainframe? (srinimf.com)
- Mainframe-How to Modernize Batch Process (2of 3) ? (srinimf.com)
- Modernizing Apps On IBM zEnterprise (drdobbs.com)