Spring Framework

org.springframework.jdbc.datasource
Class SingleConnectionDataSource

java.lang.Object
  extended by org.springframework.jdbc.datasource.AbstractDataSource
      extended by org.springframework.jdbc.datasource.AbstractDriverBasedDataSource
          extended by org.springframework.jdbc.datasource.DriverManagerDataSource
              extended by org.springframework.jdbc.datasource.SingleConnectionDataSource
All Implemented Interfaces:
java.sql.Wrapper, javax.sql.CommonDataSource, javax.sql.DataSource, DisposableBean, SmartDataSource

public class SingleConnectionDataSource
extends DriverManagerDataSource
implements SmartDataSource, DisposableBean

Implementation of SmartDataSource that wraps a single JDBC Connection which is not closed after use. Obviously, this is not multi-threading capable.

Note that at shutdown, someone should close the underlying Connection via the close() method. Client code will never call close on the Connection handle if it is SmartDataSource-aware (e.g. uses DataSourceUtils.releaseConnection).

If client code will call close() in the assumption of a pooled Connection, like when using persistence tools, set "suppressClose" to "true". This will return a close-suppressing proxy instead of the physical Connection. Be aware that you will not be able to cast this to a native OracleConnection or the like anymore; you need to use a NativeJdbcExtractor then.

This is primarily intended for testing. For example, it enables easy testing outside an application server, for code that expects to work on a DataSource. In contrast to DriverManagerDataSource, it reuses the same Connection all the time, avoiding excessive creation of physical Connections.

Author:
Rod Johnson, Juergen Hoeller
See Also:
getConnection(), Connection.close(), DataSourceUtils.releaseConnection(java.sql.Connection, javax.sql.DataSource), NativeJdbcExtractor

Field Summary
 
Fields inherited from class org.springframework.jdbc.datasource.AbstractDataSource
logger
 
Constructor Summary
SingleConnectionDataSource()
          Constructor for bean-style configuration.
SingleConnectionDataSource(java.sql.Connection target, boolean suppressClose)
          Create a new SingleConnectionDataSource with a given Connection.
SingleConnectionDataSource(java.lang.String url, boolean suppressClose)
          Create a new SingleConnectionDataSource with the given standard DriverManager parameters.
SingleConnectionDataSource(java.lang.String url, java.lang.String username, java.lang.String password, boolean suppressClose)
          Create a new SingleConnectionDataSource with the given standard DriverManager parameters.
SingleConnectionDataSource(java.lang.String driverClassName, java.lang.String url, java.lang.String username, java.lang.String password, boolean suppressClose)
          Deprecated. since Spring 2.5. Driver parameter usage is generally not recommended for a SingleConnectionDataSource. If you insist on using driver parameters directly, set up the Driver class manually before invoking this DataSource.
 
Method Summary
 void destroy()
          Close the underlying Connection.
protected  java.lang.Boolean getAutoCommitValue()
          Return whether the returned Connection's "autoCommit" setting should be overridden.
protected  java.sql.Connection getCloseSuppressingConnectionProxy(java.sql.Connection target)
          Wrap the given Connection with a proxy that delegates every method call to it but suppresses close calls.
 java.sql.Connection getConnection()
          This implementation delegates to getConnectionFromDriver, using the default username and password of this DataSource.
 java.sql.Connection getConnection(java.lang.String username, java.lang.String password)
          Specifying a custom username and password doesn't make sense with a single Connection.
 void initConnection()
          Initialize the underlying Connection via the DriverManager.
protected  boolean isSuppressClose()
          Return whether the returned Connection will be a close-suppressing proxy or the physical Connection.
protected  void prepareConnection(java.sql.Connection con)
          Prepare the given Connection before it is exposed.
 void resetConnection()
          Reset the underlying shared Connection, to be reinitialized on next access.
 void setAutoCommit(boolean autoCommit)
          Set whether the returned Connection's "autoCommit" setting should be overridden.
 void setSuppressClose(boolean suppressClose)
          Set whether the returned Connection should be a close-suppressing proxy or the physical Connection.
 boolean shouldClose(java.sql.Connection con)
          This is a single Connection: Do not close it when returning to the "pool".
 
Methods inherited from class org.springframework.jdbc.datasource.DriverManagerDataSource
getConnectionFromDriver, getConnectionFromDriverManager, setDriverClassName
 
Methods inherited from class org.springframework.jdbc.datasource.AbstractDriverBasedDataSource
getConnectionFromDriver, getConnectionProperties, getPassword, getUrl, getUsername, setConnectionProperties, setPassword, setUrl, setUsername
 
Methods inherited from class org.springframework.jdbc.datasource.AbstractDataSource
getLoginTimeout, getLogWriter, getParentLogger, isWrapperFor, setLoginTimeout, setLogWriter, unwrap
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface javax.sql.CommonDataSource
getLoginTimeout, getLogWriter, setLoginTimeout, setLogWriter
 
Methods inherited from interface java.sql.Wrapper
isWrapperFor, unwrap
 

Constructor Detail

SingleConnectionDataSource

public SingleConnectionDataSource()
Constructor for bean-style configuration.


SingleConnectionDataSource

@Deprecated
public SingleConnectionDataSource(java.lang.String driverClassName,
                                             java.lang.String url,
                                             java.lang.String username,
                                             java.lang.String password,
                                             boolean suppressClose)
Deprecated. since Spring 2.5. Driver parameter usage is generally not recommended for a SingleConnectionDataSource. If you insist on using driver parameters directly, set up the Driver class manually before invoking this DataSource.

Create a new SingleConnectionDataSource with the given standard DriverManager parameters.

Parameters:
driverClassName - the JDBC driver class name
url - the JDBC URL to use for accessing the DriverManager
username - the JDBC username to use for accessing the DriverManager
password - the JDBC password to use for accessing the DriverManager
suppressClose - if the returned Connection should be a close-suppressing proxy or the physical Connection
See Also:
DriverManager.getConnection(String, String, String)

SingleConnectionDataSource

public SingleConnectionDataSource(java.lang.String url,
                                  java.lang.String username,
                                  java.lang.String password,
                                  boolean suppressClose)
Create a new SingleConnectionDataSource with the given standard DriverManager parameters.

Parameters:
url - the JDBC URL to use for accessing the DriverManager
username - the JDBC username to use for accessing the DriverManager
password - the JDBC password to use for accessing the DriverManager
suppressClose - if the returned Connection should be a close-suppressing proxy or the physical Connection
See Also:
DriverManager.getConnection(String, String, String)

SingleConnectionDataSource

public SingleConnectionDataSource(java.lang.String url,
                                  boolean suppressClose)
Create a new SingleConnectionDataSource with the given standard DriverManager parameters.

Parameters:
url - the JDBC URL to use for accessing the DriverManager
suppressClose - if the returned Connection should be a close-suppressing proxy or the physical Connection
See Also:
DriverManager.getConnection(String, String, String)

SingleConnectionDataSource

public SingleConnectionDataSource(java.sql.Connection target,
                                  boolean suppressClose)
Create a new SingleConnectionDataSource with a given Connection.

Parameters:
target - underlying target Connection
suppressClose - if the Connection should be wrapped with a Connection that suppresses close() calls (to allow for normal close() usage in applications that expect a pooled Connection but do not know our SmartDataSource interface)
Method Detail

setSuppressClose

public void setSuppressClose(boolean suppressClose)
Set whether the returned Connection should be a close-suppressing proxy or the physical Connection.


isSuppressClose

protected boolean isSuppressClose()
Return whether the returned Connection will be a close-suppressing proxy or the physical Connection.


setAutoCommit

public void setAutoCommit(boolean autoCommit)
Set whether the returned Connection's "autoCommit" setting should be overridden.


getAutoCommitValue

protected java.lang.Boolean getAutoCommitValue()
Return whether the returned Connection's "autoCommit" setting should be overridden.

Returns:
the "autoCommit" value, or null if none to be applied

getConnection

public java.sql.Connection getConnection()
                                  throws java.sql.SQLException
Description copied from class: AbstractDriverBasedDataSource
This implementation delegates to getConnectionFromDriver, using the default username and password of this DataSource.

Specified by:
getConnection in interface javax.sql.DataSource
Overrides:
getConnection in class AbstractDriverBasedDataSource
Throws:
java.sql.SQLException
See Also:
AbstractDriverBasedDataSource.getConnectionFromDriver(String, String), AbstractDriverBasedDataSource.setUsername(java.lang.String), AbstractDriverBasedDataSource.setPassword(java.lang.String)

getConnection

public java.sql.Connection getConnection(java.lang.String username,
                                         java.lang.String password)
                                  throws java.sql.SQLException
Specifying a custom username and password doesn't make sense with a single Connection. Returns the single Connection if given the same username and password; throws a SQLException else.

Specified by:
getConnection in interface javax.sql.DataSource
Overrides:
getConnection in class AbstractDriverBasedDataSource
Throws:
java.sql.SQLException
See Also:
AbstractDriverBasedDataSource.getConnectionFromDriver(String, String)

shouldClose

public boolean shouldClose(java.sql.Connection con)
This is a single Connection: Do not close it when returning to the "pool".

Specified by:
shouldClose in interface SmartDataSource
Parameters:
con - the Connection to check
Returns:
whether the given Connection should be closed
See Also:
Connection.close()

destroy

public void destroy()
Close the underlying Connection. The provider of this DataSource needs to care for proper shutdown.

As this bean implements DisposableBean, a bean factory will automatically invoke this on destruction of its cached singletons.

Specified by:
destroy in interface DisposableBean

initConnection

public void initConnection()
                    throws java.sql.SQLException
Initialize the underlying Connection via the DriverManager.

Throws:
java.sql.SQLException

resetConnection

public void resetConnection()
Reset the underlying shared Connection, to be reinitialized on next access.


prepareConnection

protected void prepareConnection(java.sql.Connection con)
                          throws java.sql.SQLException
Prepare the given Connection before it is exposed.

The default implementation applies the auto-commit flag, if necessary. Can be overridden in subclasses.

Parameters:
con - the Connection to prepare
Throws:
java.sql.SQLException
See Also:
setAutoCommit(boolean)

getCloseSuppressingConnectionProxy

protected java.sql.Connection getCloseSuppressingConnectionProxy(java.sql.Connection target)
Wrap the given Connection with a proxy that delegates every method call to it but suppresses close calls.

Parameters:
target - the original Connection to wrap
Returns:
the wrapped Connection

Spring Framework