z/OS - Use embedded SQLJ with the DB2 for z/OS Legacy driver

Use embedded SQLJ with the DB2 for z/OS Legacy driver

Structured Query Language in Java (SQLJ) is a set of programming extensions that enable a programmer, using the Java programming language, to embed statements that provide Structured Query Language (SQL) database requests. We can use the DB2 for z/OS Legacy driver with the data access applications.

To use SQLJ with WebSphere Application Server for z/OS and the DB2 for z/OS Legacy Driver, install DB2 APAR PQ76442.

Container Managed Persistence (CMP) beans generated using SQLJ are not supported by the DB2 for z/OS Legacy Driver. Use the DB2 Universal Driver for CMPs that are generated using SQLJ.

Following are the steps required to develop applications with SQLJ that run on WebSphere Application Server for z/OS v6.0 using the DB2 for z/OS Legacy driver.
Design the application in Rational Application Developer according to the requirements, using SQLJ when necessary. For example, if you develop a bean called Test that uses BMP, code TestBean.sqlj (instead of TestBean.java).

From the DB2 for z/OS installation, copy the db2sqljclasses.zip file to a directory on the workstation, then modify the Java Build Path of the EJB JAR project to include the db2sqljclasses.zip file.

Translate the SQLJ code according to the following steps:

Locate the SQLJ file, then use ASCII mode transfer to FTP it to an HFS in the z/OS environment.

Use the sqlj command to translate the SQLJ code into Java code. Two files are produced, one with a .java extension and the other with an .ser extension.
sqlj -compile=false SQLJ_FILE_NAME

Use ASCII mode transfer for the .java file and BINARY mode transfer for the .ser file to move these files back to the directory on the workstation where the SQLJ file resides.

Refresh the project.

Generate deployment code for the application.

Export the EAR file.

Install the application

Create a data source with the DB2 for z/OS Local JDBC Provider (RRS). When you define the JDBC Provider and data source, the default values are sufficient for providing SQLJ support.

Install the application into WebSphere Application Server.
Use the data source created in Step 1 to resolve your resource references.
Customize the serialized profiles When you generate the deployment code, serialized profiles, or files with an .ser extension, that are specific to the application, are created. These profiles must be customized in a z/OS environment before they can be used.
Use binary transfer to transfer the serialized profiles to the z/OS environment on which you installed the application. Alternatively, use the Java jar command to extract the serialized profiles from the EJB JAR file in our installed EAR directory.
Use the db2profc command to customize the serialized profiles. We can get information about the various options associated with this command from the DB2 documentation; however, here are the minimum requirements to customize the profile:
db2profc -pgmname=PROGRAM_NAME PROFILE_NAME
Where:

PROGRAM_NAME must be a valid MVS™ PDS member name, and can be up to seven characters.

PROFILE_NAME is the name of the serialized profile to customize. We must run db2profc one time for each profile.

The profile customizer creates four DBRM data sets in the PDS USERNAME.DBRMLIB.DATA. The member names of the DBRMs begin with what specified as PROGRAM_NAME.

Ensure that the CLASSPATH environment variable includes:

The location of the serialized profile

The EJB JAR file in the installed EAR directory
Allocate a PDS to contain the DBRMs created. Name this PDS USERNAME.DBRMLIB.DATA, where USERNAME is the user who implements the db2profc command.
The following fields are an example:
Space units=TRACK
Primary quantity=15
Secondary quantity=5
Directory blocks=10
Record format=FB
Record length=80
Block size=27920
Data set name type=PDS
Place the existing serialized profiles, which are now customized, into a location that is part of the application classpath and that is ahead of the serialized profiles that exist in the EJB JAR file.
The output of the DB2 profile customizer and the input file have the same name. Move the output file ahead of the original serialized profile in the classpath. Alternatively, we can move the customized profile into the EJB JAR file, replacing the original. IBM recommends that you replace the original file.

IMPORTANT: If we run the db2profc command from the directory where the serialized profile exists, the profile customizer overwrites the serialized profile. Because we need only the customized version after the profile customizer has run, this is not a problem.

Bind the DBRMs into a package.
Create your database tables before binding the DBRMs. If we do not, the bind job fails.
The db2profc customization command creates a series of DBRMs that must be bound into packages. For each customized profile, four DBRMs are created.
These DBRMs:

Are located in USERNAME.DBRMLIB.DATA

All have names that begin with what specified as PROGRAM_NAME

Are numbered from 1-through-4
For example, if you log in as IBMUSER, and specified -pgmname=TESTBMP, then run the db2profc command, the four data sets, TESTBMP1, TESTBMP2, TESTBMP3, AND TESTBMP4 are created and placed in the PDS IBMUSER.DBRMLIB.DATA.
These data sets must be bound into packages with isolation of UR, CS, RS, and RR. We must run a bind for each serialized profile that you customize.
After you bind all of the DBRMs into packages, bind the packages into a plan. Name the plan whatever you like.

IMPORTANT: We must also include the JDBC packages in the package list (PKLIST) of your new plan. The default names for the JDBC packages to include are DSNJDBC.DSNJDBC1, ..., DSNJDBC.DSNJDBC4. If the installation did not use the default names for the JDBC packages, contact the DB2 administrator to determine the names of the JDBC packages that we need to include.
Following is a sample job used to bind a new plan.

One serialized profile was created while logged on as IBMUSER.

-pgmname=TESTBMP was specified to run db2profc.

The new plan is named SQLJPLAN.
//BBOOLS  JOB (516B,1025),'IBMUSER',MSGCLASS=H,CLASS=A,PRTY=14, //         NOTIFY=&SYSUID,TIME=1440,USER=IBMUSER,PASSWORD=IBMUSER, //         MSGLEVEL=(1,1)
//********************************************************************
//BINDOLS  EXEC PGM=IKJEFT01,DYNAMNBR=20
//DBRMLIB  DD  DSN=IBMUSER.DBRMLIB.DATA,DISP=SHR
//*        DD  DSN=MVSDSOM.DB2710.SDSNDBRM,DISP=SHR
//SYSTSPRT DD  SYSOUT=*
//SYSPRINT DD  SYSOUT=*
//SYSUDUMP DD  SYSOUT=*
//SYSTSIN  DD  *

 DSN SYSTEM(DB2)

 BIND -
     PACKAGE(TESTBMP) -
     QUALIFIER(IBMUSER) -
     MEMBER(TESTBMP1) -
     VALIDATE(BIND) -
     ISOLATION(UR) -
     SQLERROR(NOPACKAGE) -

 BIND -
     PACKAGE(TESTBMP) -
     QUALIFIER(IBMUSER) -
     MEMBER(TESTBMP2) -
     VALIDATE(BIND) -
     ISOLATION(CS) -
     SQLERROR(NOPACKAGE) -

 BIND -
     PACKAGE(TESTBMP) -
     QUALIFIER(IBMUSER) -
     MEMBER(TESTBMP3) -
     VALIDATE(BIND) -
     ISOLATION(RS) -
     SQLERROR(NOPACKAGE) -

 BIND -
     PACKAGE(TESTBMP) -
     QUALIFIER(IBMUSER) -
     MEMBER(TESTBMP4) -
     VALIDATE(BIND) -
     ISOLATION(RR) -
     SQLERROR(NOPACKAGE) -


 BIND PLAN(SQLJPLAN)                 -
  QUALIFIER(IBMUSER)                 -
  PKLIST(TESTBMP.*                   -
         DSNJDBC.*                 ) -
  ACTION(REPLACE) RETAIN             -
  VALIDATE(BIND)

END
/*
Grant the appropriate authority to the new plan. Use an interface to DB2, such as SPUFI, to grant the authority. Issue this command:
GRANT EXECUTE ON PLAN PLANNAME TO APPSERVERID
Where:

PLANNAME is the name of the plan that you bound.

APPSERVERID is the ID under which WebSphere Application Server runs; for example, CBSYMSR1.
Configure the data source to use the new plan

From the WAS for z/OS Administrative Console, navigate to the Data Source and select Custom Properties.

Select the Custom Property planName.

Update the value of planName with what you named your plan when it was bound.

Set enableSQLJ to true.

Stop and restart the server.

Run the application.
Related tasks

Deploy SQLJ applications