com.softtech.jdbc
Class ConnectionPool

java.lang.Object
  com.softtech.jdbc.ConnectionPool

public class ConnectionPool
extends java.lang.Object

Manages jdbc connections to the database.

Author:

Jeff S Smith

Nested Class Summary

private class

ConnectionPool.PooledConnection Pooled connection object

Field Summary

(package private) java.util.ArrayList	conPool Connection pool
private java.lang.String	conURL database connection URL
private int	dbType DatabaseType (e.g.
private java.lang.String	driverName database driver name
private java.lang.String	password database connection password
private java.lang.String	username database connection user name

Constructor Summary

ConnectionPool(java.sql.Connection con)
Constructor uses the given connection (con) as its connection.

ConnectionPool(int numPooledCon, java.lang.String driverName, java.lang.String conURL, java.lang.String username, java.lang.String password)
Constructor creates a JDBC connection using given parameters

Method Summary

private void	addConnectionsToPool(int numPooledCon) Creates database connection(s) and adds them to the pool.
void	closeAllConnections() Closes all connections in the connection pool.
(package private) void	closeConnection(java.sql.Connection con, int dbType) method closes the given connection
java.sql.Connection	getConnection() Gets available connection from the pool
int	getDbType() Get the dbType
int	getNumConInPool() Gets the number of connections in the pool
(package private) void	releaseConnection(java.sql.Connection con) Method closeConnection closes the jdbc database connection
void	releaseConnection(java.sql.Connection con, int dbType) Makes a connection available for reuse (in the connection pool)
private void	removeAnyClosedConnections()
int	resizeConnectionPool(int newSize) Attempts to resize the connection pool to the new size.

Methods inherited from class java.lang.Object

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

Field Detail

driverName

private java.lang.String driverName

database driver name

conURL

private java.lang.String conURL

database connection URL

username

private java.lang.String username

database connection user name

password

private java.lang.String password

database connection password

dbType

private int dbType

DatabaseType (e.g. DatabaseType.ORACLE)

conPool

java.util.ArrayList conPool

Connection pool

Constructor Detail

ConnectionPool

public ConnectionPool(int numPooledCon,
                      java.lang.String driverName,
                      java.lang.String conURL,
                      java.lang.String username,
                      java.lang.String password)

Constructor creates a JDBC connection using given parameters

Parameters:

databaseType -

driverName -

conURL -

username -

password -

ConnectionPool

public ConnectionPool(java.sql.Connection con)

Constructor uses the given connection (con) as its connection. Use this constructor if you want to get your connections from some custom code or from a connection pool.

Parameters:

con -

dbType -

Method Detail

addConnectionsToPool

private void addConnectionsToPool(int numPooledCon)

Creates database connection(s) and adds them to the pool.

Parameters:

numPooledCon -

driverName -

conURL -

username -

password -

getNumConInPool

public int getNumConInPool()

Gets the number of connections in the pool

Returns:

int

removeAnyClosedConnections

private void removeAnyClosedConnections()

getConnection

public java.sql.Connection getConnection()

Gets available connection from the pool

Returns:

Connection

getDbType

public int getDbType()

Get the dbType

Returns:

int

releaseConnection

void releaseConnection(java.sql.Connection con)

Method closeConnection closes the jdbc database connection

closeAllConnections

public void closeAllConnections()

Closes all connections in the connection pool.

resizeConnectionPool

public int resizeConnectionPool(int newSize)

Attempts to resize the connection pool to the new size. This method will not free any connections which are not available (in use)--so it may not resize the pool. It will always enlarge the connection pool if newSize > current size.

Parameters:

newSize -

Returns:

int new size of connection pool

releaseConnection

public void releaseConnection(java.sql.Connection con,
                              int dbType)

Makes a connection available for reuse (in the connection pool)

Parameters:

con - Connection

dbType - int database type

closeConnection

void closeConnection(java.sql.Connection con,
                     int dbType)

method closes the given connection

Parameters:

con - connection to close

dbType - type of database (used to throw appropriate exception)