2 Getting Started

Assumptions About Your Environment

The following assumptions are made about the system on which you will be running the Oracle SQLJ implementation:

• You have a standard Java environment that is operational on your system. This would typically be using a Sun Microsystems Java Development Kit (JDK), but other implementations of Java will work. Ensure that you can run Java (typically java) and the Java compiler (typically javac).

  To translate and run SQLJ applications on a Sun JDK, you must use JDK 1.2.x, 1.3.x, or 1.4.x. You must also choose an appropriate JDBC driver. There are Oracle JDBC Thin and OCI driver releases that work with each supported JDK version.

  
  

  See Also: "SQLJ Environment: Key Scenarios and Guidelines"

  
  

• You can already run JDBC applications in your environment.

  If you are using Oracle Database and Oracle JDBC drivers, then you should complete the steps in Chapter 2, "Getting Started", of the Oracle Database JDBC Developer's Guide and Reference.You can also refer to Chapter 1, "Introducing JDBC", of that document for information about the Oracle JDBC drivers and how to decide which is appropriate for your situation.

Requirements for Using the Oracle SQLJ Implementation

The following are required to use the Oracle SQLJ implementation:

• A JDBC driver implementing the standard java.sql JDBC interfaces

  The Oracle SQLJ product works with any standard JDBC driver.

• A database system that is accessible using your JDBC driver

• Class files for the SQLJ translator

  Translator-related classes are available in the following file:

  ORACLE_HOME/sqlj/lib/translator.jar

• Class files for the SQLJ run time.

  Several SQLJ run time versions are available. You must select a run time version that is compatible with your Java environment and JDBC driver (these are all in ORACLE_HOME/sqlj/lib):

  • runtime12.jar: For use with Oracle9i or Oracle10g JDBC drivers under JDK 1.2.x, 1.3.x, or 1.4.x, providing full ISO SQLJ functionality

  • runtime12ee.jar: For use with Oracle9i or Oracle10g JDBC drivers in a Java2 Platform, Enterprise Edition (J2EE) environment that includes JDK 1.2.x, 1.3.x, or 1.4.x, providing full ISO SQLJ functionality

  • runtime.jar: For use with older Oracle JDBC drivers (intended for Oracle8i release 8.1.7)

SQLJ Environment: Key Scenarios and Guidelines

To ensure that you have a fully working environment, you must consider several aspects of your environment: SQLJ and its code generation mode, JDBC, and the JDK. This section first discusses the two main Oracle scenarios of supported combinations, and then discusses some important general guidelines.

Scenario 1: Oracle-Specific Code

The following is a typical environment setup for Oracle-specific code generation:

• SQLJ code generation: -codegen=oracle (default)

• SQLJ translation library: translator.jar

• SQLJ run time library: runtime12.jar or runtime12ee.jar

• JDBC drivers: Oracle9i release 1 (9.0.1) or later

• JDK version: 1.2.x, 1.3.x, or 1.4.x

Scenario 2: ISO Standard Code

The following is a typical environment setup for ISO standard code generation:

• SQLJ code generation: -codegen=iso

• SQLJ translation library: translator.jar

• SQLJ run time library: runtime12.jar or runtime12ee.jar with JDK 1.2.x or later and Oracle9i Database release 1 (9.0.1) or later JDBC drivers

• JDBC drivers: Any Oracle JDBC release (appropriate for SQLJ run time library as noted in the preceding point)

• JDK version: 1.2.x, 1.3.x, or 1.4.x

Environment Scenarios: Key Guidelines

The following are the important guidelines and considerations regarding your environment for running the Oracle SQLJ implementation:

• In general, use the same versions of the SQLJ library, JDBC library, and JDK in translating and compiling all components of your application.

• Be aware of the following cross-compatibility considerations:

  • If you want to run against different Oracle JDBC driver releases, then translate against the earlier release. Generated code is optimized toward the JDBC driver in the CLASSPATH during translation.

  • For cross-compatibility, avoid using declared connection context classes. If you use JPublisher, then use the default settings for the -compatible and -context options.

    
    

    See Also: Oracle Database JPublisher User's Guide for information about these options.

    
    

  • For maximum cross-compatibility, you can use the generic runtime.jar library. However, this library has disadvantages, such as not supporting the oracle.jdbc.OracleXXX interfaces. This causes problems in the middle tier. Note that SQLJ in the Oracle9i Application Server middle tier requires release 2 (9.0.2) or later version of Oracle Application Server.

Environment Considerations

This section discusses the key environmental issue and limitations. The following list notes environmental issues and limitations:

• With the default -codegen=oracle setting, you cannot use the generic runtime.jar library.

• You can run the application against a JDK version that is at least as high as the version you translated the code under. If you translate your code under JDK 1.2.x, then you can run the application either under JDK 1.2.x or 1.3.x or 1.4.x.

SQLJ Backward Compatibility

You must keep in mind the following points regarding backward compatibility of the Oracle SQLJ implementation:

• Code generated with an earlier release of the SQLJ translator can continue to run and compile against current run time libraries. However, this is subject to the cross-compatibility limitations discussed in "Environment Considerations".

• Oracle-specific translator output, that is, code generated with the default -codegen=oracle setting, must be created and executed using the runtime12.jar or runtime12ee.jar library. In addition:

  • Such code will be executable under future Oracle JDBC and SQLJ implementations.

  • Such code, however, will not be executable under earlier releases of Oracle JDBC drivers and the Oracle SQLJ run time. In these circumstances, you will have to retranslate the code.

  Also remember that Oracle-specific code is not portable.

• ISO standard translator output, that is, code generated with the -codegen=iso setting, can be created and executed against an earlier Oracle JDBC implementation using the current runtime.jar library.

Check for Availability of SQLJ and Demo Applications

Following are the release-specific notes regarding availability of SQLJ and its demo applications:

• SQLJ and its demo applications are available from the Oracle Technology Network (OTN) at the following location:

  http://www.oracle.com/technology/sample_code/tech/java/sqlj_jdbc/sqlj.html

• For Oracle Database 10g, SQLJ and its demo applications are included with the installation.

• For Oracle9i Database release 2 (9.2), SQLJ and its demo applications are included if you do a full installation or if you otherwise install HTTPClient.

Check for Installed Directories and Files

Verify that the following directories have been installed and are populated:

Directories for JDBC

If you are using one of the Oracle JDBC drivers, refer to the Oracle Database JDBC Developer's Guide and Reference for information about JDBC files that should be installed on your system.

Directories for SQLJ

Installing the Oracle Database 10g Java environment will include, among other things, installing a sqlj directory under your ORACLE_HOME directory. The sqlj directory contains the following subdirectories:

• demo (demo applications, including some referenced in this chapter)

• doc

• lib (.jar files containing class files for SQLJ)

Check whether all these directories have been created and populated, especially lib.

The structure is similar if you download SQLJ from the OTN:

http://www.oracle.com/technology/software/tech/java/sqlj_jdbc/index.html

The ORACLE_HOME/bin directory contains utilities for all Java product areas, including the SQLJ and JPublisher executable files.

Set the Path and Classpath

Ensure that the PATH and CLASSPATH environment variables have the necessary settings for the Oracle SQLJ implementation and the Oracle JDBC implementation, if applicable.

PATH and CLASSPATH for JDBC

If you are using one of the Oracle JDBC drivers, then you will need the JDBC library that is appropriate for your environment.

Classes for JDK 1.2.x or later are in classes12.jar. Classes for JDK 1.4.x specifically are in ojdbc14.jar. Presuming you use a Sun Microsystems JDK, ensure that the appropriate library file name is in your classpath setting. There might also be alternative JDBC driver libraries available, such as classes12_g.jar, which enables driver debugging information to be printed.

For more information about libraries and required path and classpath settings for the Oracle JDBC implementation, refer to the Oracle Database JDBC Developer's Guide and Reference.

Path and Classpath for SQLJ

Set the PATH and CLASSPATH environment variables as follows for the Oracle SQLJ implementation:

• Setting PATH

  To run the sqlj script, which invokes the SQLJ translator, without having to fully specify its path, verify that the PATH environment variable has been updated to include the following:

  ORACLE_HOME/bin
  
  

  Use backslash (\) for Microsoft Windows. Replace ORACLE_HOME with your actual Oracle home directory.

• Setting CLASSPATH

  Update the CLASSPATH environment variable to include the current directory as well as the following:

  ORACLE_HOME/sqlj/lib/translator.jar
  
  

  Use backslash (\) for Microsoft Windows. Replace ORACLE_HOME with your actual Oracle home directory.

  In addition, you must include one of the following run time libraries in the CLASSPATH:

  ORACLE_HOME/sqlj/lib/runtime12.jar
  ORACLE_HOME/sqlj/lib/runtime12ee.jar
  ORACLE_HOME/sqlj/lib/runtime.jar
  
  

  
  

  See Also: "Requirements for Using the Oracle SQLJ Implementation"

  
  
  
  

  Note: You will not be able to run the SQLJ translator if you do not add a run time library. You must specify a run time library as well as the translator library in the CLASSPATH. To see if SQLJ is installed correctly, and to see the version information for SQLJ, JDBC, and Java, run the following command: % sqlj -version-long

  
  

Verify Installation of the sqljutl Package

The sqljutl package is required for online checking of stored procedures and functions in an Oracle Database instance. Beginning with Oracle8i Database release 8.1.5, it is installed automatically under the SYS schema during installation of the server-side Java virtual machine (JVM) for a Java-enabled database. If your database is not Java-enabled, then you will have to manually install this package.

If you want to verify the installation of sqljutl, then issue the following SQL command from SQL*Plus:

describe sys.sqljutl

This should result in a brief description of the package.

If you get a message indicating that the package cannot be found, or if you want to install an updated version of the package, then you can install it by using SQL*Plus to run the sqljutl.sql script (or sqljutl8.sql for Oracle8i Database), which is located at:

ORACLE_HOME/sqlj/lib/sqljutl.sql

Set Up the Run Time Connection

This section describes how to update the connect.properties file to configure your Oracle connection for run time. The file is in the demo directory and looks something like the following:

jdbc:oracle:thin:@localhost:1521:orcl

jdbc:oracle:thin:@localhost:1521/myservice

# Users should uncomment one of the following URLs or add their own.
# (If using Thin, edit as appropriate.)
#sqlj.url=jdbc:oracle:thin:@localhost:1521/myservice
#sqlj.url=jdbc:oracle:oci:@
#
# User name and password here
sqlj.user=scott
sqlj.password=tiger

Connecting with an Oracle JDBC Driver

With Oracle9i Database or later versions, use oci in the connect string for the Oracle JDBC OCI driver in any new code. For backward compatibility, however, oci8 is still accepted. Therefore, you do not have to change existing code.

If you are using the JDBC Thin driver, then uncomment the thin URL line in connect.properties and edit it as appropriate for your Oracle connection. Use the same URL that was specified when your JDBC driver was set up.

Create a Table to Verify the Database

The following tests assume a table called SALES. Compile and run TestInstallCreateTable as follows:

% javac TestInstallCreateTable.java
% java TestInstallCreateTable

This will create the table for you if the database and the JDBC driver are working and the connection is set up properly in the connect.properties file.

If you do not want to use TestInstallCreateTable, then you can create the SALES table using the following SQL statement:

CREATE TABLE SALES (
      ITEM_NUMBER NUMBER,
      ITEM_NAME CHAR(30),
      SALES_DATE DATE, 
      COST NUMBER, 
      SALES_REP_NUMBER NUMBER,
      SALES_REP_NAME CHAR(20));

Verify the JDBC Driver

If you want to further test the Oracle JDBC driver, then use the TestInstallJDBC demo. Verify that your connection is set up properly in connect.properties. Then, compile and run TestInstallJDBC, as follows:

% javac TestInstallJDBC.java
% java TestInstallJDBC

The program should print:

Hello, JDBC! 

Verify the SQLJ Translator and Run Time

Now translate and run the TestInstallSQLJ demo, a SQLJ application that has functionality similar to that of TestInstallJDBC. Use the following command to translate the source:

% sqlj TestInstallSQLJ.sqlj

Note that this command also compiles the application.

On a UNIX environment, the sqlj script is in ORACLE_HOME/bin, which should already be in the PATH. On Windows, use the sqlj.exe executable in the bin directory. The SQLJ translator.jar file has the class files for the SQLJ translator and run time. It is located in ORACLE_HOME/sqlj/lib and should already be in the CLASSPATH.

Now run the application as follows:

% java TestInstallSQLJ

The program should print:

Hello, SQLJ!

Verify the SQLJ Translator Connection to the Database

If the SQLJ translator is able to connect to a database, then it can provide online semantics-checking of your SQL operations during translation. The SQLJ translator is written in Java and uses JDBC to get information it needs from a database connection that you specify. You provide the connection parameters for online semantics-checking using the sqlj script command line or using a SQLJ properties file, which is sqlj.properties by default.

While still in the demo directory, edit the sqlj.properties file and update, comment, or uncomment the sqlj.password, sqlj.url, and sqlj.driver lines, as appropriate, to reflect your database connection information. For assistance, refer to the comments in the sqlj.properties file.

Following is an example of what the appropriate driver, URL, and password settings might be if you are using the Oracle JDBC OCI driver.

sqlj.url=jdbc:oracle:oci:@
sqlj.driver=oracle.jdbc.OracleDriver
sqlj.password=tiger

Online semantics-checking is enabled as soon as you specify a user name for the translation-time connection. You can specify the user name either by uncommenting the sqlj.user line in the sqlj.properties file or by using the -user command-line option. The user, password, url, and driver options all can be set either on the command line or in the properties file.

You can test online semantics-checking by translating the TestInstallSQLJChecker.sqlj file located in the demo directory, as follows (or using another user name, if appropriate):

% sqlj -user=scott TestInstallSQLJChecker.sqlj

This should produce the following error message if you are using one of the Oracle JDBC drivers:

TestInstallSQLJChecker.sqlj:41: Warning: Unable to check SQL query. Error returned by database is: ORA-00904: invalid column name

Edit TestInstallSQLJChecker.sqlj to fix the error on line 41. The column name should be ITEM_NAME instead of ITEM_NAMAE. Once you make this change, you can translate and run the application without error using the following commands:

% sqlj -user=scott TestInstallSQLJChecker.sqlj
% java  TestInstallSQLJChecker

If everything works, then the following line is displayed:

Hello, SQLJ Checker!