com.samskivert.jdbc

Class DataSourceConnectionProvider

java.lang.Object

com.samskivert.jdbc.DataSourceConnectionProvider

All Implemented Interfaces:

ConnectionProvider

public class DataSourceConnectionProvider
extends Object
implements ConnectionProvider

Provides connections using a pair of DataSource instances (one for read-only operations and one for read-write operations). Note: if transactions are going to be used, the data sources must be pooled data sources, otherwise bad things will happen.

Constructor Summary

Constructors

Constructor and Description
DataSourceConnectionProvider(String url, DataSource readSource, DataSource writeSource) Creates a connection provider that will obtain connections from the supplied read-only and read-write sources.

Method Summary

Modifier and Type	Method and Description
void	connectionFailed(String ident, boolean readOnly, Connection conn, SQLException error) Called by the repository if a failure occurred on the connection.
Connection	getConnection(String ident, boolean readOnly) Obtains a database connection based on the supplied database identifier.
Connection	getTxConnection(String ident) Returns a connection that can be used in a transaction.
String	getURL(String ident) Returns the URL associated with this database identifier.
void	releaseConnection(String ident, boolean readOnly, Connection conn) Releases a database connection when it is no longer needed by the repository.
void	releaseTxConnection(String ident, Connection conn) Releases a connection obtained by ConnectionProvider.getTxConnection(java.lang.String).
void	shutdown() Shuts down this connection provider, closing all connections currently in the pool.
void	txConnectionFailed(String ident, Connection conn, SQLException error) Reports failure of a connection obtained by ConnectionProvider.getTxConnection(java.lang.String).

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DataSourceConnectionProvider

public DataSourceConnectionProvider(String url,
                                    DataSource readSource,
                                    DataSource writeSource)

Creates a connection provider that will obtain connections from the supplied read-only and read-write sources. The ident mechanism is not used by this provider. Responsibility for the lifecycle of the supplied datasources is left to the caller and is not managed by the connection provider (shutdown() does nothing).

Parameters:

url - a URL prefix that can be used by the DatabaseLiaison to identify the type of database being accessed by the supplied data sources, this should be one of "jdbc:mysql" or "jdbc:postgresql" as those are the only two types of database currently supported.

Method Detail

getConnection

public Connection getConnection(String ident,
                                boolean readOnly)
                         throws PersistenceException

Description copied from interface: ConnectionProvider

Obtains a database connection based on the supplied database identifier. The repository expects to have exclusive use of this connection instance until it releases it. This connection will be released subsequently with a call to ConnectionProvider.releaseConnection(java.lang.String, boolean, java.sql.Connection) or ConnectionProvider.connectionFailed(java.lang.String, boolean, java.sql.Connection, java.sql.SQLException) depending on the circumstances of the release. close() will not be called on the connection. It is up to the connection provider to close the connection when it is released if appropriate.

Specified by:

getConnection in interface ConnectionProvider

Parameters:

ident - the database connection identifier.

readOnly - whether or not the connection may be to a read-only mirror of the repository.

Returns:

an active JDBC connection (which may have come from a connection pool).

Throws:

PersistenceException - thrown if a problem occurs trying to open the requested connection.

releaseConnection

public void releaseConnection(String ident,
                              boolean readOnly,
                              Connection conn)

Description copied from interface: ConnectionProvider

Releases a database connection when it is no longer needed by the repository.

Specified by:

releaseConnection in interface ConnectionProvider

Parameters:

ident - the database identifier used when obtaining this connection.

readOnly - the same value that was passed to ConnectionProvider.getConnection(java.lang.String, boolean) to obtain this connection.

conn - the connection to release (back into the pool or to be closed if pooling is not going on).

connectionFailed

public void connectionFailed(String ident,
                             boolean readOnly,
                             Connection conn,
                             SQLException error)

Description copied from interface: ConnectionProvider

Called by the repository if a failure occurred on the connection. It is expected that the connection will be disposed of and subsequent calls to getConnection will return a freshly established connection to the database.

Specified by:

connectionFailed in interface ConnectionProvider

Parameters:

ident - the database identifier used when obtaining this connection.

readOnly - the same value that was passed to ConnectionProvider.getConnection(java.lang.String, boolean) to obtain this connection.

conn - the connection that failed.

error - the error thrown by the connection (which may be used to determine if the connection should be closed or can be reused).

getTxConnection

public Connection getTxConnection(String ident)
                           throws PersistenceException

Description copied from interface: ConnectionProvider

Returns a connection that can be used in a transaction. See ConnectionProvider.getConnection(java.lang.String, boolean). Note: transaction connections are never read-only. What would be the point?

Specified by:

getTxConnection in interface ConnectionProvider

Throws:

PersistenceException

releaseTxConnection

public void releaseTxConnection(String ident,
                                Connection conn)

Description copied from interface: ConnectionProvider

Releases a connection obtained by ConnectionProvider.getTxConnection(java.lang.String). See ConnectionProvider.releaseConnection(java.lang.String, boolean, java.sql.Connection).

Specified by:

releaseTxConnection in interface ConnectionProvider

txConnectionFailed

public void txConnectionFailed(String ident,
                               Connection conn,
                               SQLException error)

Description copied from interface: ConnectionProvider

Reports failure of a connection obtained by ConnectionProvider.getTxConnection(java.lang.String). See ConnectionProvider.connectionFailed(java.lang.String, boolean, java.sql.Connection, java.sql.SQLException).

Specified by:

txConnectionFailed in interface ConnectionProvider

getURL

public String getURL(String ident)

Description copied from interface: ConnectionProvider

Returns the URL associated with this database identifier. This should be the same value that would be used if ConnectionProvider.getConnection(java.lang.String, boolean) were called.

Specified by:

getURL in interface ConnectionProvider

shutdown

public void shutdown()

Description copied from interface: ConnectionProvider

Shuts down this connection provider, closing all connections currently in the pool. This should only be called once all active connections have been released with ConnectionProvider.releaseConnection(java.lang.String, boolean, java.sql.Connection).

Specified by:

shutdown in interface ConnectionProvider