Interface DataSource

A factory for connections to the physical data source that this DataSource object represents. An alternative to the DriverManager facility, a DataSource object is the preferred means of getting a connection. An object that implements the DataSource interface will typically be registered with a naming service based on the Java™ Naming and Directory (JNDI) API.

The DataSource interface is implemented by a driver vendor. There are three types of implementations:

1. Basic implementation -- produces a standard Connection object
2. Connection pooling implementation -- produces a Connection object that will automatically participate in connection pooling. This implementation works with a middle-tier connection pooling manager.
3. Distributed transaction implementation -- produces a Connection object that may be used for distributed transactions and almost always participates in connection pooling. This implementation works with a middle-tier transaction manager and almost always with a connection pooling manager.

A DataSource object has properties that can be modified when necessary. For example, if the data source is moved to a different server, the property for the server can be changed. The benefit is that because the data source's properties can be changed, any code accessing that data source does not need to be changed.

A driver that is accessed via a DataSource object does not register itself with the DriverManager. Rather, a DataSource object is retrieved though a lookup operation and then used to create a Connection object. With a basic implementation, the connection obtained through a DataSource object is identical to a connection obtained through the DriverManager facility.

An implementation of DataSource must include a public no-arg constructor.

Methods

getConnection

Connection getConnection()
                  throws SQLException

Returns:

a connection to the data source

Throws:

SQLException - if a database access error occurs

SQLTimeoutException - when the driver has determined that the timeout value specified by the setLoginTimeout method has been exceeded and has at least tried to cancel the current database connection attempt

getConnection

Connection getConnection(String username,
                         String password)
                  throws SQLException

Parameters:

username - the database user on whose behalf the connection is being made

password - the user's password

Returns:

a connection to the data source

Throws:

SQLException - if a database access error occurs

SQLTimeoutException - when the driver has determined that the timeout value specified by the setLoginTimeout method has been exceeded and has at least tried to cancel the current database connection attempt

Since:

1.4