com.altair.hwm.database.dbmodel
Class HWMDBCxnPool

java.lang.Object
  com.altair.hwm.database.dbmodel.HWMDBCxnPool

All Implemented Interfaces:

java.lang.Runnable

public class HWMDBCxnPool
extends java.lang.Object
implements java.lang.Runnable

Title: HWMDBCxnPool

Description: This class handles the database connection pool. This has been modified to suit Altair's requirements

Company: Altair Engineering, Inc.

A class for preallocating, recycling, and managing JDBC connections. Taken from Core Servlets and JavaServer Pages from Prentice Hall and Sun Microsystems Press, http://www.coreservlets.com/. © 2000 Marty Hall; may be freely used or adapted.

Constructor Summary

HWMDBCxnPool(java.lang.String strSQLInfoClass, java.lang.String strURL, int nPort, java.lang.String strDBName, java.lang.String strUser, java.lang.String strPwd, int nInitialCxns, int nMaxCxns)
Constructor

Method Summary

void	CloseAllConnections() Close all the connections.
void	FreeConnection(java.sql.Connection cxn) Make the cxn available to other clients.
java.sql.Connection	GetConnection() Returns a free connection.
HWMDatabaseInfo	GetDatabaseInfo() Returns the database info class
int	GetTotalConnections() Returns the total connections created
java.lang.String	GetURL() Returns the URL of the databse
java.lang.String	GetUser() Returns the user name who connects to the database
void	run() The run method of the thread
java.lang.String	toString() String representation of this class

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

HWMDBCxnPool

public HWMDBCxnPool(java.lang.String strSQLInfoClass,
                    java.lang.String strURL,
                    int nPort,
                    java.lang.String strDBName,
                    java.lang.String strUser,
                    java.lang.String strPwd,
                    int nInitialCxns,
                    int nMaxCxns)
             throws java.lang.Exception

Constructor

Parameters:

strSQLInfoClass - The SQL info class which will be used for connecting to DB

strURL - The URL to the db machine

nPort - The port to which the DB server is listening to

strDBName - The DB name to connect to

strUser - The user name

strPwd - The password

nInitialCxns - The initial number of connections

nMaxCxns - The maximum number of connections allowed

Throws:

java.lang.Exception

Method Detail

GetConnection

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

Returns a free connection. If there are no more free connections, then a new connection is created until the max limit is recahed. If the max limit is reached, then an exception is thrown

Returns:

Connection Connection to database

Throws:

java.sql.SQLException

run

public void run()

The run method of the thread

Specified by:

run in interface java.lang.Runnable

FreeConnection

public void FreeConnection(java.sql.Connection cxn)

Make the cxn available to other clients. This will also notify the clients waiting for a free cxn (so that they do not have to wait until the new cxn is created)

Parameters:

cxn - the connection that needs to be made available

GetTotalConnections

public int GetTotalConnections()

Returns the total connections created

Returns:

int The total connections created

CloseAllConnections

public void CloseAllConnections()

Close all the connections. Use with caution: be sure no connections are in use before calling. Note that you are not required to call this when done with a ConnectionPool, since connections are guaranteed to be closed when garbage collected. But this method gives more control regarding when the connections are closed.

GetUser

public java.lang.String GetUser()

Returns the user name who connects to the database

Returns:

String User who connects to the database

GetURL

public java.lang.String GetURL()

Returns the URL of the databse

Returns:

String URL of the database

GetDatabaseInfo

public HWMDatabaseInfo GetDatabaseInfo()

Returns the database info class

Returns:

HWMdatabaseInfo The database info class

toString

public java.lang.String toString()

String representation of this class

Overrides:

toString in class java.lang.Object

Returns:

String String representation of this class