CICS® provides a
channel-based interface to call a Java™ program
that is running in a JVM server. This interface is provided for vendor
implementations or support packs that use JVM servers for non-OSGi Java programs. It is not for use
with OSGi Java programs.
About this task
The channel-based interfaces are provided as a mechanism
for vendors to create and access Java programs
that are running in a JVM server. The interface is provided for compatibility
only and must not be used for user Java applications.
The JVM server is primarily provided as an OSGi framework for Java applications, providing granular
life cycle management of applications.
Procedure
- Edit the JVM profile for the JVM server.
The
default profile is DFHOSGI.jvmprofile, but this is specifically set
up for an OSGi framework. Add in the following options to run non-OSGi Java workloads:
- Use the class path options to specify the class path
of the Java programs.
-
Use the SETUP_CLASSES option to add classes that run during the initialization
of the JVM to set up the environment for all applications. For example, you might add a class that
sets the state for a number of global static variables or a class that acquires a connection to Db2®. Setup classes cannot contain
JCICS methods.
- Use the TERMINATION_CLASSES option
to add classes that run during the shutdown of the JVM. For example,
you might add a class that resolves any outstanding states that are
left by the applications or that perform some additional logging.
Termination classes cannot contain JCICS methods.
- Use the THREAD_TIMEOUT to specify how
many seconds CICS waits for
the setup and termination classes to finish running during the initialization
or shutdown of the JVM server.
- Save the JVM profile in the directory specified by the JVMPROFILEDIR system
initialization parameter.
- Create a JVMSERVER resource that specifies the JVM profile.
- Create a program that creates a channel called DFHSJJS-V1
and populates a set of control containers.
The mandatory
containers are DFHSJ-JVMSERVER (which identifies the target JVMSERVER
resource), and DFHSJ-USERCLASS (which identifies the target Java class).
- Use a LINK command to link from the
program to the CICS-supplied program DFHSJJI. The DFHSJJI program
reads the control containers and attaches to the requested JVM server.