JDBC Type 4 Driver Programmer's Reference for SQL/MX Release 3.2.1

3. Using a properties file for the JDBC driver. The properties file is passed as a command-line
parameter. The format to enter the properties file in the command-line is:
-Dt4sqlmx.properties=location-of-the-properties-file-on-disk
For example, -Dt4sqlmx.properties=C:\temp\t4props
For information about the properties file, see “Creating and Using a Properties File”
(page 37) in the “Type 4 Driver Properties” (page 33).
4. Using JDBC properties with the -D option in the command line. If used, this option applies
to all JDBC connections using the DriverManager within the Java application. The
format in the command line is:
-Dt4sqlmx.property_name=property_value
For example, -Dt4sqlmx.maxStatements=1024
Stored Procedures
Java applications can use the JDBC standard CallableStatement interface to run stored
procedures (SPJs) by using the CALL statement. For more information, see the HP Nonstop SQL/MX
Release 3.2 Guide to Stored Procedures in Java.
The following SPJ features are not supported:
• executeBatch for callableStatements
• setXXX() methods with parameter names instead of parameter numbers
Starting with SQL/MX Release 3.0, the feature of SPJ returning a java.sql.ResultSet is
available from T1249V20^ABT.
Connection Pooling
The Type 4 driver provides an implementation of connection pooling, where a cache of physical
database connections are assigned to a client session and reused for the database activity. If
connection pooling is active, connections are not physically closed. The connection is returned to
its connection pool when the Connection.close() method is called. The next time a connection
is requested by the client, the driver will return the pooled connection, and not a new physical
connection.
• The connection pooling feature is available when the JDBC application uses either the
DriverManager class or DataSource interface to obtain a JDBC connection. The connection
pool size is determined by the maxPoolSize property value and minPoolSize property
value.
• By default, connection pooling is disabled. To enable connection pooling, set the
maxPoolSize property to an integer value greater than 0 (zero).
• Manage connection pooling by using the following Type 4 driver properties:
maxPoolSize◦
◦ minPoolSize
◦ initialPoolSize
◦ maxStatements
• When used with the DriverManager class, the Type 4 driver has a connection-pool manager
that determines which connections are pooled together by a unique value for the following
combination of properties:
url
catalog
Stored Procedures 25