org.apache.commons.dbcp
Class PoolingConnection

java.lang.Object
  |
  +--org.apache.commons.dbcp.AbandonedTrace
        |
        +--org.apache.commons.dbcp.DelegatingConnection
              |
              +--org.apache.commons.dbcp.PoolingConnection

All Implemented Interfaces:

java.sql.Connection, org.apache.commons.pool.KeyedPoolableObjectFactory

public class PoolingConnection

extends DelegatingConnection

implements java.sql.Connection, org.apache.commons.pool.KeyedPoolableObjectFactory

A DelegatingConnection that pools PreparedStatements.

My prepareStatement(java.lang.String) methods, rather than creating a new PreparedStatement each time, may actually pull the PreparedStatement from a pool of unused statements. The Statement.close() method of the returned PreparedStatement doesn't actually close the statement, but rather returns it to my pool. (See PoolablePreparedStatement.)

Author:

Rodney Waldhoff (rwaldhof@us.britannica.com)

See Also:

PoolablePreparedStatement

Field Summary

protected org.apache.commons.pool.KeyedObjectPool

_pstmtPool My pool of PreparedStatements.

Fields inherited from class org.apache.commons.dbcp.DelegatingConnection

_closed, _conn

Fields inherited from interface java.sql.Connection

TRANSACTION_NONE, TRANSACTION_READ_COMMITTED, TRANSACTION_READ_UNCOMMITTED, TRANSACTION_REPEATABLE_READ, TRANSACTION_SERIALIZABLE

Constructor Summary

PoolingConnection(java.sql.Connection c)
Constructor.

PoolingConnection(java.sql.Connection c, org.apache.commons.pool.KeyedObjectPool pool)
Constructor.

Method Summary

void	activateObject(java.lang.Object key, java.lang.Object obj) My KeyedPoolableObjectFactory method for activating PreparedStatements.
void	close() Close and free all PreparedStatements from my pool, and close my underlying connection.
protected java.lang.Object	createKey(java.lang.String sql) Create a PoolingConnection.PStmtKey for the given arguments.
protected java.lang.Object	createKey(java.lang.String sql, int resultSetType, int resultSetConcurrency) Create a PoolingConnection.PStmtKey for the given arguments.
void	destroyObject(java.lang.Object key, java.lang.Object obj) My KeyedPoolableObjectFactory method for destroying PreparedStatements.
java.lang.Object	makeObject(java.lang.Object obj) My KeyedPoolableObjectFactory method for creating PreparedStatements.
protected java.lang.String	normalizeSQL(java.lang.String sql) Normalize the given SQL statement, producing a cannonical form that is semantically equivalent to the original.
void	passivateObject(java.lang.Object key, java.lang.Object obj) My KeyedPoolableObjectFactory method for passivating PreparedStatements.
java.sql.PreparedStatement	prepareStatement(java.lang.String sql) Create or obtain a PreparedStatement from my pool.
java.sql.PreparedStatement	prepareStatement(java.lang.String sql, int resultSetType, int resultSetConcurrency) Create or obtain a PreparedStatement from my pool.
java.lang.String	toString()
boolean	validateObject(java.lang.Object key, java.lang.Object obj) My KeyedPoolableObjectFactory method for validating PreparedStatements.

Methods inherited from class org.apache.commons.dbcp.DelegatingConnection

activate, checkOpen, clearWarnings, commit, createStatement, createStatement, getAutoCommit, getCatalog, getDelegate, getInnermostDelegate, getMetaData, getTransactionIsolation, getTypeMap, getWarnings, isClosed, isReadOnly, nativeSQL, passivate, prepareCall, prepareCall, rollback, setAutoCommit, setCatalog, setDelegate, setReadOnly, setTransactionIsolation, setTypeMap

Methods inherited from class org.apache.commons.dbcp.AbandonedTrace

addTrace, clearTrace, getConfig, getLastUsed, getTrace, printStackTrace, removeTrace, setLastUsed, setLastUsed, setStackTrace

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.sql.Connection

clearWarnings, commit, createStatement, createStatement, createStatement, getAutoCommit, getCatalog, getHoldability, getMetaData, getTransactionIsolation, getTypeMap, getWarnings, isClosed, isReadOnly, nativeSQL, prepareCall, prepareCall, prepareCall, prepareStatement, prepareStatement, prepareStatement, prepareStatement, releaseSavepoint, rollback, rollback, setAutoCommit, setCatalog, setHoldability, setReadOnly, setSavepoint, setSavepoint, setTransactionIsolation, setTypeMap

Field Detail

_pstmtPool

protected org.apache.commons.pool.KeyedObjectPool _pstmtPool

My pool of PreparedStatements.

Constructor Detail

PoolingConnection

public PoolingConnection(java.sql.Connection c)

Constructor.

Parameters:

c - the underlying Connection.

PoolingConnection

public PoolingConnection(java.sql.Connection c,
                         org.apache.commons.pool.KeyedObjectPool pool)

Constructor.

Parameters:

c - the underlying Connection.

Method Detail

activateObject

public void activateObject(java.lang.Object key,
                           java.lang.Object obj)

My KeyedPoolableObjectFactory method for activating PreparedStatements. (Currently a no-op.)

Specified by:

activateObject in interface org.apache.commons.pool.KeyedPoolableObjectFactory

Parameters:

key - ignored

obj - ignored

close

public void close()
           throws java.sql.SQLException

Close and free all PreparedStatements from my pool, and close my underlying connection.

Specified by:

close in interface java.sql.Connection

Overrides:

close in class DelegatingConnection

java.sql.SQLException

createKey

protected java.lang.Object createKey(java.lang.String sql)

Create a PoolingConnection.PStmtKey for the given arguments.

createKey

protected java.lang.Object createKey(java.lang.String sql,
                                     int resultSetType,
                                     int resultSetConcurrency)

Create a PoolingConnection.PStmtKey for the given arguments.

destroyObject

public void destroyObject(java.lang.Object key,
                          java.lang.Object obj)

My KeyedPoolableObjectFactory method for destroying PreparedStatements.

Specified by:

destroyObject in interface org.apache.commons.pool.KeyedPoolableObjectFactory

Parameters:

key - ignored

obj - the PreparedStatement to be destroyed.

makeObject

public java.lang.Object makeObject(java.lang.Object obj)

My KeyedPoolableObjectFactory method for creating PreparedStatements.

Specified by:

makeObject in interface org.apache.commons.pool.KeyedPoolableObjectFactory

Parameters:

obj - the key for the PreparedStatement to be created

normalizeSQL

protected java.lang.String normalizeSQL(java.lang.String sql)

Normalize the given SQL statement, producing a cannonical form that is semantically equivalent to the original.

passivateObject

public void passivateObject(java.lang.Object key,
                            java.lang.Object obj)

My KeyedPoolableObjectFactory method for passivating PreparedStatements. Currently invokes PreparedStatement.clearParameters().

Specified by:

passivateObject in interface org.apache.commons.pool.KeyedPoolableObjectFactory

Parameters:

key - ignored

obj - a PreparedStatement

prepareStatement

public java.sql.PreparedStatement prepareStatement(java.lang.String sql)
                                            throws java.sql.SQLException

Create or obtain a PreparedStatement from my pool.

Specified by:

prepareStatement in interface java.sql.Connection

Overrides:

prepareStatement in class DelegatingConnection

Returns:

a PoolablePreparedStatement

java.sql.SQLException

prepareStatement

public java.sql.PreparedStatement prepareStatement(java.lang.String sql,
                                                   int resultSetType,
                                                   int resultSetConcurrency)
                                            throws java.sql.SQLException

Create or obtain a PreparedStatement from my pool.

Specified by:

prepareStatement in interface java.sql.Connection

Overrides:

prepareStatement in class DelegatingConnection

Returns:

a PoolablePreparedStatement

java.sql.SQLException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

validateObject

public boolean validateObject(java.lang.Object key,
                              java.lang.Object obj)

My KeyedPoolableObjectFactory method for validating PreparedStatements.

Specified by:

validateObject in interface org.apache.commons.pool.KeyedPoolableObjectFactory

Parameters:

key - ignored

obj - ignored

Returns:

true