org.mmbase.module.database
Class MultiConnection

java.lang.Object
  org.mmbase.module.database.ConnectionWrapper
      org.mmbase.module.database.MultiConnection

All Implemented Interfaces:

Connection

public class MultiConnection

extends ConnectionWrapper

MultiConnection is a replacement class for Connection it provides you a multiplexed and reuseable connections from the connection pool. The main function of this class is to 'log' (keep) the last sql statement passed to it. Another function is to keep state (i.e. notifying that it is busy), and to make itself available again to teh connectionpool once it is finished (closed).

Version:

$Id: MultiConnection.java,v 1.44 2006/07/03 11:59:16 johannes Exp $

Author:

vpro, Pierre van Rooden

Warning: Contains Database Legacy Code

It would possibly be better to pass the logging of the sql query to the code that calls the conenction, rather than place it in the conenction itself, as it's implementation leads to conflicts between various JDBC versions. This also goes for freeing the connection once it is 'closed'.

Field Summary

static int	CON_BUSY
static int	CON_FAILED
static int	CON_FINISHED
static int	CON_UNUSED
static long	queries
int	state

Fields inherited from class org.mmbase.module.database.ConnectionWrapper

con

Fields inherited from interface java.sql.Connection

TRANSACTION_NONE, TRANSACTION_READ_COMMITTED, TRANSACTION_READ_UNCOMMITTED, TRANSACTION_REPEATABLE_READ, TRANSACTION_SERIALIZABLE

Constructor Summary

MultiConnection(MultiPool parent, Connection con)

Method Summary

protected boolean	checkAfterException() Tries to fix the this connection, if it proves to be broken.
boolean	checkSQLError(Exception e)
void	claim()
void	close() Close connections
Statement	createStatement() createStatement returns an SQL Statement object
Statement	createStatement(int resultSetType, int resultSetConcurrency) createStatement returns an SQL Statement object
Statement	createStatement(int type, int concurrency, int holdability)
String	getLastSQL()
Connection	getRealConnection() Return the underlying real connection.
int	getStartTime() Returns the moment on which the last SQL statement was started in seconds after 1970.
long	getStartTimeMillis() Returns the moment on which the last SQL statement was started in milliseconds after 1970.
String	getStateString()
int	getUsage()
void	realclose() Close connections
void	release()
void	setAutoCommit(boolean enableAutoCommit) If "autoCommit" is true, then all subsequent SQL statements will be executed and committed as individual transactions.
void	setLastSQL(String sql) Called just before every prepare statement.
String	toString()

Methods inherited from class org.mmbase.module.database.ConnectionWrapper

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

Methods inherited from class java.lang.Object

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

Field Detail

CON_UNUSED

public static final int CON_UNUSED

See Also:

Constant Field Values

CON_BUSY

public static final int CON_BUSY

See Also:

Constant Field Values

CON_FINISHED

public static final int CON_FINISHED

See Also:

Constant Field Values

CON_FAILED

public static final int CON_FAILED

See Also:

Constant Field Values

queries

public static long queries

state

public int state

Constructor Detail

MultiConnection

public MultiConnection(MultiPool parent,
                       Connection con)

Since:

MMBase-1.7

To Do:

in 1.7 this method was made public,document why?

Warning: No Java Documentation Available.

Method Detail

getStateString

public String getStateString()

Warning: No Java Documentation Available.

setLastSQL

public void setLastSQL(String sql)

Description copied from class: ConnectionWrapper

Called just before every prepare statement. Can be overridden, because this default implementation is empty.

Overrides:

setLastSQL in class ConnectionWrapper

Warning: No Java Documentation Available.

getLastSQL

public String getLastSQL()

Warning: No Java Documentation Available.

createStatement

public Statement createStatement()
                          throws SQLException

createStatement returns an SQL Statement object

Specified by:

createStatement in interface Connection

Overrides:

createStatement in class ConnectionWrapper

Throws:

SQLException

checkAfterException

protected boolean checkAfterException()
                               throws SQLException

Tries to fix the this connection, if it proves to be broken. It is supposed to be broken if the query "SELECT 1 FROM