The IBM JZOS Batch Toolkit for z/OS SDKs is a set of tools that enhances Java batch capabilities and use of system interfaces on z/OS. It includes a native launcher for running Java applications directly as batch jobs or started tasks, and a toolkit of Java classes that make access to traditional z/OS data and key system services directly available from Java applications. Additional system services include console communication, multiline WTO (write to operator), and return code passing capability. In addition, JZOS provides facilities for flexible configuration of the run-time environment, and it allows intermediate data to be seen via z/OS System Display and Search Facility (SDSF). Java applications can be fully integrated as job steps in order to augment existing batch applications. Although the JZOS launcher only applies to Java batch jobs, the toolkit classes may be used in any z/OS Java application.

The combination of the launcher, data access, added system services, and environmental enhancements make running Java on z/OS as batch jobs easier, particularly for traditional z/OS programmers. The net result of these enhancements is that the look and feel of running Java applications is much closer to other z/OS batch jobs, and the way Java batch can be managed is now like other z/OS batch applications written in COBOL, PL/I, or other compiled languages.

How does it work?

The batch launcher and toolkit extends the z/OS J2SE products with a set of Java classes and additional C++ code. Java applications can be launched directly as batch jobs on z/OS along with using the custom launcher. The JZOS set of Java class libraries extends the function available in the standard Java product. The extensions provide APIs for Java access to z/OS operating system services and access to z/OS-specific data types, including VSAM data.

A version of the JZOS Batch Toolkit is included as part of the IBM Java SDK for z/OS products. As part of an announced and IBM-supported product, the JZOS function is supported through normal IBM z/OS corrective service procedures.

This alphaWorks® version contains new and additional functionality on an "as-is" basis that is available for customer evaluation and feedback. Some of these new features may eventually be available in the SDK product version, but some features, such as the cookbook, will not become part of the supported products.

What are the most recent functional improvements?

JZOS Version 2.3.2 includes the following additions:

• new package com.ibm.jzos.wlm with selected Workload Manager (WLM) apis
• jzos_recgen.jar includes the com.ibm.jzos.fields package, so that it has everything  necessary to generate code on other platforms.
• the CatalogSearch class has been enhanced, allowing for dynamic selection criteria modification.

The JZOS Cookbook 1.0.6 includes a fix for Cookbook 1.0.5, which includes the following:

• a new Chapter on building rich web interfaces with Flex
• a new Eclipse project with two versions of the Catalog Search rich web application

What are the previous functional improvements?

The JZOS Cookbook 1.0.4 includes the following additional chapters:

• Using DFSORT from JZOS
• Implementing Big Web Services using Axis2

The JZOS Cookbook 1.0.3 includes the following additional chapters:

• Generating Java Record Classes
• Analyzing Application Performance with Java Interactive Profiler
• Analyzing Performance with JinsightLive for System z

The JZOS Cookbook 1.0.2 develops an example inventory application in order to demonstrate the following:

• development and testing of z/OS Java applications using Eclipse
• deployment to z/OS using Apache Ant
• running of z/OS batch Java applications using the JZOS Launcher
• demonstration of how to use the following Java and z/OS programming interfaces:
  • SQL database access
  • data set access -- sequential and VSAM
  • XML processing
  • mapping of COBOL-described records to Java
• demonstration of the use of popular open-source Java tools:
  • Spring framework
  • Apache Derby
  • Apache Commons Digester, Logging, and BeanUtils
  • Apache Log4J
  • JUnit
  • Apache Ant
• complete source, packaged in an Eclipse project, that can be used as a template for new development.

JZOS Version 2.3.0 includes the following additions:

• support for z/OS Java SDK 6
• AccessMethodServices (IDCAMS interface)
• Enqueue (interface to ISGENQ)
• ZUtil.substituteSystemSymbols() methods (ASASYMB system symbol service)
• ZFile.getFullyQualififiedDSN(String, boolean) method
• new sample class: EnqUpdatePdsMember

The IBM JZOS Batch Toolkit for z/OS SDKs (formerly known as JZOS) was developed by Kirk Wolf and Steve Goetze, principals in the company Dovetailed Technologies, LLC.