DataSource
public
interface
DataSource
implements
CommonDataSource,
Wrapper
javax.sql.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
JavaTM Naming and Directory (JNDI) API.
The DataSource
interface is implemented by a driver vendor.
There are three types of implementations:
- Basic implementation -- produces a standard
Connection
object - Connection pooling implementation -- produces a
Connection
object that will automatically participate in connection pooling. This implementation works with a middle-tier connection pooling manager. - 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.
Summary
Public methods | |
---|---|
abstract
Connection
|
getConnection()
Attempts to establish a connection with the data source that
this |
abstract
Connection
|
getConnection(String username, String password)
Attempts to establish a connection with the data source that
this |
Inherited methods | |
---|---|
Public methods
getConnection
public abstract Connection getConnection ()
Attempts to establish a connection with the data source that
this DataSource
object represents.
Returns | |
---|---|
Connection |
a connection to the data source |
Throws | |
---|---|
SQLException |
if a database access error occurs |
getConnection
public abstract Connection getConnection (String username, String password)
Attempts to establish a connection with the data source that
this DataSource
object represents.
Parameters | |
---|---|
username |
String : the database user on whose behalf the connection is
being made |
password |
String : the user's password |
Returns | |
---|---|
Connection |
a connection to the data source |
Throws | |
---|---|
SQLException |
if a database access error occurs |