JDBC Type 2 Driver Programmer's Reference for SQL/MX Release 3.1 (H06.23+, J06.12+)

Connection Pooling with the DriverManager Class
Connection Pooling by an Application Server
Usually, in a three-tier environment, the application server implements the connection pooling component.
How to implement this component is described in these topics:
Guidelines for Implementing an Application Server to Use Connection Pooling
Standard ConnectionPoolDataSource Object Properties
Guidelines for Implementing an Application Server to Use Connection Pooling
The application server maintains a cache of the PooledConnection objects created by using
ConnectionPoolDataSource interface. When the client requests a connection object, the application
looks for the suitable
PooledConnection object. The lookup criteria and other methods are specific to
the application server.
The application server implements the ConnectionEventListener interface and registers the listener
object with the
PooledConnection object. The JDBC/MX driver notifies the listener object with a
connectionClosed event when the application is finished using the Connection object. Then, the
connection pooling component can reuse this
PooledConnection object for future requests. The
JDBC/MX driver also notifies the listener object with
connectionErrorOccurred event when the
PooledConnection object fails to initialize the connection. The application server's connection pooling
component should discard the
PooledConnection when such a connection error event occurs.
The application server manages the connection pool by using the SQLMXConnectionPoolDataSource,
which implements the
ConnectionPoolDataSource interface. Use the getter and setter methods,
provided by JDBC/MX, to set the connection pool configuration properties listed in the table of
Standard ConnectionPoolDataSource Object Properties. In addition to these standard properties, the
ConnectionPoolDataSource includes the JDBC/MX driver-specific properties as described under
Connection Using the DataSource Interface.
Standard ConnectionPoolDataSource Object Properties
Note: The application server defines the meaning of these properties.
Property Name Type Description
maxStatements int
The total number of PreparedStatement objects that the pool
should cache. This total includes both free objects and objects
in use. 0 (zero) disables statement pooling.
initialPoolSize int
The number of physical connections the pool should contain
when it is created.
minPoolSize int
The number of physical connections the pool should keep
available at all times. 0 (zero) indicates no maximum size.
maxPoolSize int
The maximum number of physical connections that the pool
should contain. 0 (zero) indicates no maximum size.
maxIdleTime int
The number of seconds that a physical connection should
remain unused in the pool before the connection is closed. 0
(zero) indicates no limit.