cics-java-liberty-jdbc

Sample JDBC Java EE web application demonstrating how to access a DB2 database from a web servlet in CICS Liberty.

Repository structure

• projects/ - Eclipse projects suitable for importing into a CICS Explorer environment.
• etc/ - Liberty server configuration files

Samples overview

• com.ibm.cicsdev.jdbc.web - Dynamic web project containing the SimpleJDBCServlet servlet. The servlet uses the DoJDBC class which connects to DB2 by obtaining a DataSource via a JNDI lookup and returns the current timestamp from DB2
• com.ibm.cicsdev.jdbc.web.cicsbundle - CICS bundle project that references the WAR (Dynamic web project) bundle part for deployment in a CICS bundle

Pre-requisites

• CICS TS V5.3 with APAR PI77502 or CICS TS V5.4
• Java SE 7 or later on the z/OS system
• CICS Explorer V5.4 with the IBM CICS SDK for Java EE and Liberty feature installed available here
• IBM Db2 for z/OS

Configuration

The sample code can be deployed as a WAR file into a CICS Liberty JVM server. CICS Liberty can be configured to use either a local DB2 database with JDBC type 2 connectivity, or a remote database with a JDBC type 4 connectivity. The SimpleJDBCServlet servlet can then be used to display the current timestamp from DB2

To import the samples into Eclipse

1. Import the projects into CICS Explorer using File -> Import -> General -> Existing projects into workspace
2. Resolve the build path errors on the Dynamic web project using the following menu from the web project: Build Path -> Configure Build Path -> Libraries -> Add Library -> CICS with Java EE and Liberty and select the version of CICS TS for deployment (either CICS TS V5.3 or CICS TS V5.4)

To configure CICS for JDBC type 2 connectivity to DB2

1. Create a Liberty JVM server as described in 4 easy steps
2. Update the CICS STEPLIB with the DB2 SDSNLOAD and SDSNLOD2 libraries
3. Configure CICS DB2CONN, DB2TRAN and DB2ENTRY resource definitions as described in How you can define the CICS DB2 connection
4. Bind the DB2 plan that is specified in the CICS DB2CONN or DB2ENTRY definition with a PKLIST of NULLID.*
5. Add the following properties in the JVM profile to set the location of the DB2 drivers to allow CICS to automatically configure the default DataSource

-Dcom.ibm.cics.jvmserver.wlp.autoconfigure=true
-Dcom.ibm.cics.jvmserver.wlp.jdbc.driver.location=/usr/lpp/db2v12/jdbc

Where /usr/lpp/db2v12/jdbc is the location of the DB2 JDBC driver

An example Liberty server configuration of a DataSource with a type 2 connection is supplied in etc/config/type-2-server.xml. Configuration with DataSource and a type 4 connection is in etc/config/type-4-server.xml

To deploy the sample into a CICS region

1. Change the name of the JVMSERVER in the .warbundle file from DFHWLP to the name of the JVMSERVER resource defined in CICS.
2. Using the CICS Explorer export the com.ibm.cicsdev.jdbc.web.cicsbundle project to a zFS directory.
3. Define and install a CICS BUNDLE resource definition referring to the deployed bundle directory on zFS in step 2, and ensure all resources are enabled.

Running the sample

• The servlet is accessed with the following URL: http://host:port/com.ibm.cicsdev.jdbc.web/

If the test is successful, you will see a response similar to the following written to the browser:

SimpleJDBCServlet: DB2 CurrentTimeStamp = 2017-08-02 11:28:46.18055

Reference

• Sample SQLJ Git repository cics-java-liberty-sqlj
• CICS Knowledge Center Configuring a Liberty JVM server
• CICS Knowledge Center Configuring a JVM server to support DB2

License

This project is licensed under Apache License Version 2.0.