org.dmonix.jdbc
Class DMConnectionPool

java.lang.Object
  org.dmonix.jdbc.DMConnectionPool

public class DMConnectionPool

extends java.lang.Object

The class makes connections available to calling program in its getConnection method.
This method searches for an available connection in the connection pool.
If no connection is available from the pool, a new connection is created.
If a connection is available from the pool, the getConnection method leases the connection and returns it to the calling program.

Copyright: Copyright (c) 2003

Company: dmonix.org

Version:

1.0

Author:

Peter Nerg

Constructor Summary

DMConnectionPool(java.lang.String url, java.lang.String user, java.lang.String password, int initialSize)
Constructs a pool of the initial size.

DMConnectionPool(java.lang.String url, java.lang.String user, java.lang.String password, int initialSize, boolean autoCommit)
Constructs a pool of the initial size.

Method Summary

void	closeConnections() This will close and remove all connections from the pool.
java.sql.Connection	getConnection() The method searches for an available connection in the connection pool.
void	reapConnections() The method will remove any hanging, dead connections.
void	removeConnection(DMConnection conn) This will remove one connection from the pool.
void	returnConnection(DMConnection conn) This will return a connection to the pool.

Methods inherited from class java.lang.Object

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

Constructor Detail

DMConnectionPool

public DMConnectionPool(java.lang.String url,
                        java.lang.String user,
                        java.lang.String password,
                        int initialSize,
                        boolean autoCommit)
                 throws java.sql.SQLException

Constructs a pool of the initial size.

Parameters:

url - The URL for the connection

user - The user for the connection

password - The password for the connection

initialSize - The initial size of the pool

autoCommit - If the connections shall be autocommiting

Throws:

java.sql.SQLException

DMConnectionPool

public DMConnectionPool(java.lang.String url,
                        java.lang.String user,
                        java.lang.String password,
                        int initialSize)
                 throws java.sql.SQLException

Constructs a pool of the initial size.

Parameters:

url - The URL for the connection

user - The suer for the connection

password - The password for the connection

initialSize - The initial size of the pool

Throws:

java.sql.SQLException

Method Detail

reapConnections

public void reapConnections()

The method will remove any hanging, dead connections.
A connection is dead if the following conditions are met.

• The connection is flagged as being in use.
• The connection is older than a preset connection time out.
• The connection fails a validation check.

closeConnections

public void closeConnections()

This will close and remove all connections from the pool.

removeConnection

public void removeConnection(DMConnection conn)

This will remove one connection from the pool.

Parameters:

conn - The connection to remove

getConnection

public java.sql.Connection getConnection()
                                  throws java.sql.SQLException

The method searches for an available connection in the connection pool.
If no connection is available from the pool, the method is put on hold using wait(). If a connection is available from the pool, the getConnection method leases the connection and returns it to the calling program

Returns:

The connection

Throws:

java.sql.SQLException

returnConnection

public void returnConnection(DMConnection conn)

This will return a connection to the pool.
If the pool was previously empty, the method invokes notify() in order to release any thread waiting in the method getConnection()

Parameters:

conn - The connection to return