org.mmbase.module.database
Class MultiConnection

java.lang.Object
  |
  +--org.mmbase.module.database.MultiConnection

All Implemented Interfaces:

java.sql.Connection

public class MultiConnection

extends java.lang.Object

implements java.sql.Connection

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).
This classs has been expanded with dummy code that enables it to be easily adapted for compilation with jdk1.4 and JDBC 3. In order to compile using this new API, comment-out the Savepoint inner class. If you actually use a JDBC 3 driver, you may also want to adapt the new JDBC 3 methods, so that they pass their call to the driver, instead of throwing an UnsupportedOperationException.

Version:

$Id: MultiConnection.java,v 1.16 2002/11/07 07:17:10 kees Exp $

Author:

vpro, Pierre van Rooden

Field Summary

static int	CON_BUSY
static int	CON_FAILED
static int	CON_FINISHED
static int	CON_UNUSED
int	state

Fields inherited from interface java.sql.Connection

TRANSACTION_NONE, TRANSACTION_READ_COMMITTED, TRANSACTION_READ_UNCOMMITTED, TRANSACTION_REPEATABLE_READ, TRANSACTION_SERIALIZABLE

Constructor Summary

protected

MultiConnection() protected constructor for extending classes, so they can use this with for example only a connection..

Method Summary

boolean	checkSQLError(java.lang.Exception e)
void	claim()
void	clearWarnings() clear Warnings
void	close() Close connections
void	commit() Perform commit
java.sql.Statement	createStatement() createStatement returns an SQL Statement object
java.sql.Statement	createStatement(int i, int y) createStatement returns an SQL Statement object
java.sql.Statement	createStatement(int type, int concurrency, int holdability) Creates a Statement object that will generate ResultSet objects with the given type, concurrency, and holdability.
boolean	getAutoCommit() get AutoCommit mode
java.lang.String	getCatalog() The "catalog" name
int	getHoldability() Retrieves the current holdability of ResultSet objects created using this Connection object.
java.lang.String	getLastSQL()
java.sql.DatabaseMetaData	getMetaData() Advanced features: You can obtain a DatabaseMetaData object to get information about the target database.
int	getStartTime()
long	getStartTimeMillis()
java.lang.String	getStateString()
int	getTransactionIsolation()
java.util.Map	getTypeMap()
int	getUsage()
java.sql.SQLWarning	getWarnings() getWarnings will return any warning information related to the current connection.
boolean	isClosed() isClosed returns true if the connection is closed, which can occur either due to an explicit call on "close" or due to some fatal error on the connection.
boolean	isReadOnly() Is this database readonly ?
java.lang.String	nativeSQL(java.lang.String query) Convert the given generic SQL statement to the drivers native SQL.
java.sql.CallableStatement	prepareCall(java.lang.String sql) prepareCall create a pre-compiled SQL statement that is a call on a stored procedure.
java.sql.CallableStatement	prepareCall(java.lang.String sql, int i, int y) prepareCall create a pre-compiled SQL statement that is a call on a stored procedure.
java.sql.CallableStatement	prepareCall(java.lang.String sql, int type, int concurrency, int holdability) Creates a CallableStatement object that will generate ResultSet objects with the given type, concurrency, and holdability.
java.sql.PreparedStatement	prepareStatement(java.lang.String sql) prepareStatement creates a pre-compiled SQL PreparedStatement object.
java.sql.PreparedStatement	prepareStatement(java.lang.String sql, int autoGeneratedKeys) Creates a default PreparedStatement object that has the capability to retrieve auto-generated keys.
java.sql.PreparedStatement	prepareStatement(java.lang.String sql, int[] columnIndexes) Creates a default PreparedStatement object capable of returning the auto-generated keys designated by the given array.
java.sql.PreparedStatement	prepareStatement(java.lang.String sql, int i, int y) prepareStatement creates a pre-compiled SQL PreparedStatement object.
java.sql.PreparedStatement	prepareStatement(java.lang.String sql, int type, int concurrency, int holdability) Creates a PreparedStatement object that will generate ResultSet objects with the given type, concurrency, and holdability.
java.sql.PreparedStatement	prepareStatement(java.lang.String sql, java.lang.String[] columnNames) Creates a default PreparedStatement object capable of returning the auto-generated keys designated by the given array.
void	realclose() Close connections
void	release()
void	releaseSavepoint(org.mmbase.module.database.MultiConnection.Savepoint savepoint) Removes the given Savepoint object from the current transaction.
void	rollback() Perform rollback
void	rollback(org.mmbase.module.database.MultiConnection.Savepoint savepoint) Undoes all changes made after the given Savepoint object was set.
void	setAutoCommit(boolean enableAutoCommit) If "autoCommit" is true, then all subsequent SQL statements will be executed and committed as individual transactions.
void	setCatalog(java.lang.String catalog) The "catalog" selects a sub-space of the target database.
void	setHoldability(int holdability) Changes the holdability of ResultSet objects created using this Connection object to the given holdability.
void	setLastSQL(java.lang.String sql)
void	setReadOnly(boolean readOnly) You can put a connection in read-only mode as a hint to enable database optimizations.
org.mmbase.module.database.MultiConnection.Savepoint	setSavepoint() Creates an unnamed savepoint in the current transaction and returns the new Savepoint object that represents it.
org.mmbase.module.database.MultiConnection.Savepoint	setSavepoint(java.lang.String name) Creates a savepoint with the given name in the current transaction and returns the new Savepoint object that represents it.
void	setTransactionIsolation(int level) You can call the following method to try to change the transaction isolation level on a newly opened connection, using one of the TRANSACTION_* values.
void	setTypeMap(java.util.Map mp)
java.lang.String	toString()

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

CON_BUSY

public static final int CON_BUSY

CON_FINISHED

public static final int CON_FINISHED

CON_FAILED

public static final int CON_FAILED

state

public int state

Constructor Detail

MultiConnection

protected MultiConnection()

protected constructor for extending classes, so they can use this with for example only a connection..

Method Detail

getStateString

public java.lang.String getStateString()

setLastSQL

public void setLastSQL(java.lang.String sql)

getLastSQL

public java.lang.String getLastSQL()

createStatement

public java.sql.Statement createStatement()
                                   throws java.sql.SQLException

createStatement returns an SQL Statement object

Specified by:

createStatement in interface java.sql.Connection

prepareStatement

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

prepareStatement creates a pre-compiled SQL PreparedStatement object.

Specified by:

prepareStatement in interface java.sql.Connection

prepareCall

public java.sql.CallableStatement prepareCall(java.lang.String sql)
                                       throws java.sql.SQLException

prepareCall create a pre-compiled SQL statement that is a call on a stored procedure.

Specified by:

prepareCall in interface java.sql.Connection

nativeSQL

public java.lang.String nativeSQL(java.lang.String query)
                           throws java.sql.SQLException

Convert the given generic SQL statement to the drivers native SQL.

Specified by:

nativeSQL in interface java.sql.Connection

setAutoCommit

public void setAutoCommit(boolean enableAutoCommit)
                   throws java.sql.SQLException

If "autoCommit" is true, then all subsequent SQL statements will be executed and committed as individual transactions. Otherwise (if "autoCommit" is false) then subsequent SQL statements will all be part of the same transaction , which must be explicitly committed with either a "commit" or "rollback" call. By default new connections are initialized with autoCommit "true".

Specified by:

setAutoCommit in interface java.sql.Connection

getAutoCommit

public boolean getAutoCommit()
                      throws java.sql.SQLException

get AutoCommit mode

Specified by:

getAutoCommit in interface java.sql.Connection

commit

public void commit()
            throws java.sql.SQLException

Perform commit

Specified by:

commit in interface java.sql.Connection

rollback

public void rollback()
              throws java.sql.SQLException

Perform rollback

Specified by:

rollback in interface java.sql.Connection

close

public void close()
           throws java.sql.SQLException

Close connections

Specified by:

close in interface java.sql.Connection

realclose

public void realclose()
               throws java.sql.SQLException

Close connections

isClosed

public boolean isClosed()
                 throws java.sql.SQLException

isClosed returns true if the connection is closed, which can occur either due to an explicit call on "close" or due to some fatal error on the connection.

Specified by:

isClosed in interface java.sql.Connection

getMetaData

public java.sql.DatabaseMetaData getMetaData()
                                      throws java.sql.SQLException

Advanced features: You can obtain a DatabaseMetaData object to get information about the target database.

Specified by:

getMetaData in interface java.sql.Connection

setReadOnly

public void setReadOnly(boolean readOnly)
                 throws java.sql.SQLException

You can put a connection in read-only mode as a hint to enable database optimizations. Note that setReadOnly cannot be called while in the middle of a transaction.

Specified by:

setReadOnly in interface java.sql.Connection

isReadOnly

public boolean isReadOnly()
                   throws java.sql.SQLException

Is this database readonly ?

Specified by:

isReadOnly in interface java.sql.Connection

setCatalog

public void setCatalog(java.lang.String catalog)
                throws java.sql.SQLException

The "catalog" selects a sub-space of the target database.

Specified by:

setCatalog in interface java.sql.Connection

getCatalog

public java.lang.String getCatalog()
                            throws java.sql.SQLException

The "catalog" name

Specified by:

getCatalog in interface java.sql.Connection

setTransactionIsolation

public void setTransactionIsolation(int level)
                             throws java.sql.SQLException

You can call the following method to try to change the transaction isolation level on a newly opened connection, using one of the TRANSACTION_* values. Use the DatabaseMetaData class to find what isolation levels are supported by the current database. Note that setTransactionIsolation cannot be called while in the middle of a transaction.

Specified by:

setTransactionIsolation in interface java.sql.Connection

getTransactionIsolation

public int getTransactionIsolation()
                            throws java.sql.SQLException

Specified by:

getTransactionIsolation in interface java.sql.Connection

getWarnings

public java.sql.SQLWarning getWarnings()
                                throws java.sql.SQLException

getWarnings will return any warning information related to the current connection. Note that SQLWarning may be a chain.

Specified by:

getWarnings in interface java.sql.Connection

clearWarnings

public void clearWarnings()
                   throws java.sql.SQLException

clear Warnings

Specified by:

clearWarnings in interface java.sql.Connection

checkSQLError

public boolean checkSQLError(java.lang.Exception e)

claim

public void claim()

release

public void release()

getUsage

public int getUsage()

getStartTime

public int getStartTime()

getStartTimeMillis

public long getStartTimeMillis()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

prepareCall

public java.sql.CallableStatement prepareCall(java.lang.String sql,
                                              int i,
                                              int y)
                                       throws java.sql.SQLException

prepareCall create a pre-compiled SQL statement that is a call on a stored procedure.

Specified by:

prepareCall in interface java.sql.Connection

setTypeMap

public void setTypeMap(java.util.Map mp)
                throws java.sql.SQLException

Specified by:

setTypeMap in interface java.sql.Connection

getTypeMap

public java.util.Map getTypeMap()
                         throws java.sql.SQLException

Specified by:

getTypeMap in interface java.sql.Connection

createStatement

public java.sql.Statement createStatement(int i,
                                          int y)
                                   throws java.sql.SQLException

createStatement returns an SQL Statement object

Specified by:

createStatement in interface java.sql.Connection

prepareStatement

public java.sql.PreparedStatement prepareStatement(java.lang.String sql,
                                                   int i,
                                                   int y)
                                            throws java.sql.SQLException

prepareStatement creates a pre-compiled SQL PreparedStatement object.

Specified by:

prepareStatement in interface java.sql.Connection

setHoldability

public void setHoldability(int holdability)
                    throws java.sql.SQLException

Changes the holdability of ResultSet objects created using this Connection object to the given holdability.

Parameters:

holdability - the holdability, one of ResultSet.HOLD_CURSORS_OVER_COMMIT or ResultSet.CLOSE_CURSORS_AT_COMMIT

Since:

MMBase 1.5, JDBC 1.4

getHoldability

public int getHoldability()
                   throws java.sql.SQLException

Retrieves the current holdability of ResultSet objects created using this Connection object.

Returns:

the holdability, one of ResultSet.HOLD_CURSORS_OVER_COMMIT or ResultSet.CLOSE_CURSORS_AT_COMMIT

Since:

MMBase 1.5, JDBC 1.4

setSavepoint

public org.mmbase.module.database.MultiConnection.Savepoint setSavepoint()
                                                                  throws java.sql.SQLException

Creates an unnamed savepoint in the current transaction and returns the new Savepoint object that represents it.

Returns:

the new Savepoint object

Since:

MMBase 1.5, JDBC 1.4

setSavepoint

public org.mmbase.module.database.MultiConnection.Savepoint setSavepoint(java.lang.String name)
                                                                  throws java.sql.SQLException

Creates a savepoint with the given name in the current transaction and returns the new Savepoint object that represents it.

Parameters:

name - a String containing the name of the savepoint

Returns:

the new Savepoint object

Since:

MMBase 1.5, JDBC 1.4

rollback

public void rollback(org.mmbase.module.database.MultiConnection.Savepoint savepoint)
              throws java.sql.SQLException

Undoes all changes made after the given Savepoint object was set. This method should be used only when auto-commit has been disabled.

Parameters:

savepoint - the Savepoint object to roll back to

Since:

MMBase 1.5, JDBC 1.4

releaseSavepoint

public void releaseSavepoint(org.mmbase.module.database.MultiConnection.Savepoint savepoint)
                      throws java.sql.SQLException

Removes the given Savepoint object from the current transaction. Any reference to the savepoint after it have been removed will cause an SQLException to be thrown

Parameters:

savepoint - the Savepoint object to remove

Since:

MMBase 1.5, JDBC 1.4

createStatement

public java.sql.Statement createStatement(int type,
                                          int concurrency,
                                          int holdability)
                                   throws java.sql.SQLException

Creates a Statement object that will generate ResultSet objects with the given type, concurrency, and holdability.

Parameters:

type - one of the following ResultSet constants: ResultSet.TYPE_FORWARD_ONLY, ResultSet.TYPE_SCROLL_INSENSITIVE, or ResultSet.TYPE_SCROLL_SENSITIVE

concurrency - - one of the following ResultSet constants: ResultSet.CONCUR_READ_ONLY or ResultSet.CONCUR_UPDATABLE

holdability - - one of the following ResultSet constants: ResultSet.HOLD_CURSORS_OVER_COMMIT or ResultSet.CLOSE_CURSORS_AT_COMMIT

Returns:

a new Statement object

Since:

MMBase 1.5, JDBC 1.4

prepareStatement

public java.sql.PreparedStatement prepareStatement(java.lang.String sql,
                                                   int type,
                                                   int concurrency,
                                                   int holdability)
                                            throws java.sql.SQLException

Creates a PreparedStatement object that will generate ResultSet objects with the given type, concurrency, and holdability.

Parameters:

sql - a String object that is the SQL statement to be sent to the database

type - one of the following ResultSet constants: ResultSet.TYPE_FORWARD_ONLY, ResultSet.TYPE_SCROLL_INSENSITIVE, or ResultSet.TYPE_SCROLL_SENSITIVE

concurrency - - one of the following ResultSet constants: ResultSet.CONCUR_READ_ONLY or ResultSet.CONCUR_UPDATABLE

holdability - - one of the following ResultSet constants: ResultSet.HOLD_CURSORS_OVER_COMMIT or ResultSet.CLOSE_CURSORS_AT_COMMIT

Returns:

a new PreparedStatement object

Since:

MMBase 1.5, JDBC 1.4

prepareCall

public java.sql.CallableStatement prepareCall(java.lang.String sql,
                                              int type,
                                              int concurrency,
                                              int holdability)
                                       throws java.sql.SQLException

Creates a CallableStatement object that will generate ResultSet objects with the given type, concurrency, and holdability.

Parameters:

sql - a String object that is the SQL statement to be sent to the database

type - one of the following ResultSet constants: ResultSet.TYPE_FORWARD_ONLY, ResultSet.TYPE_SCROLL_INSENSITIVE, or ResultSet.TYPE_SCROLL_SENSITIVE

concurrency - - one of the following ResultSet constants: ResultSet.CONCUR_READ_ONLY or ResultSet.CONCUR_UPDATABLE

holdability - - one of the following ResultSet constants: ResultSet.HOLD_CURSORS_OVER_COMMIT or ResultSet.CLOSE_CURSORS_AT_COMMIT

Returns:

a new CallableStatement object

Since:

MMBase 1.5, JDBC 1.4

prepareStatement

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

Creates a default PreparedStatement object that has the capability to retrieve auto-generated keys. The given constant tells the driver whether it should make auto-generated keys available for retrieval. This array is ignored if the SQL statement is not an INSERT statement.

Parameters:

sql - a String object that is the SQL statement to be sent to the database

autoGeneratedKeys - a flag indicating whether auto-generated keys should be returned;

Returns:

a new PreparedStatement object

Since:

MMBase 1.5, JDBC 1.4

prepareStatement

public java.sql.PreparedStatement prepareStatement(java.lang.String sql,
                                                   int[] columnIndexes)
                                            throws java.sql.SQLException

Creates a default PreparedStatement object capable of returning the auto-generated keys designated by the given array. This array contains the indexes of the columns in the target table that contain the auto-generated keys that should be made available. This array is ignored if the SQL statement is not an INSERT statement.

Parameters:

sql - a String object that is the SQL statement to be sent to the database

columnIndexes - an array of column indexes indicating the columns that should be returned from the inserted row or rows

Returns:

a new PreparedStatement object

Since:

MMBase 1.5, JDBC 1.4

prepareStatement

public java.sql.PreparedStatement prepareStatement(java.lang.String sql,
                                                   java.lang.String[] columnNames)
                                            throws java.sql.SQLException

Creates a default PreparedStatement object capable of returning the auto-generated keys designated by the given array. This array contains the names of the columns in the target table that contain the auto-generated keys that should be returned. This array is ignored if the SQL statement is not an INSERT statement.

Parameters:

sql - a String object that is the SQL statement to be sent to the database

columnNames - an array of column names indicating the columns that should be returned from the inserted row or rows

Returns:

a new PreparedStatement object

Since:

MMBase 1.5, JDBC 1.4