org.bibalex.daf.handlers.dbhandler
Class DBConnection

java.lang.Object
  org.bibalex.daf.handlers.dbhandler.DBConnection

public class DBConnection
extends java.lang.Object

Author:

shehab.kamal and mohammed.abuouda@bibalex.org

Field Summary

private java.sql.Connection	connection Holds the connection to be used by each method.
private java.lang.String	dbDriver Holds the database driver that is used in assocaition with the database url to create a connection.
private java.lang.String	dbUrl Holds the Database url on the form jdbc:subprotocol:subname.
private static java.lang.String	driver Holds the database driver that is used in assocaition with the database url to create a connection.
private static DBConnection	instance Holds the sole instace of DBConnection.
private static java.sql.Connection	Sqlconnection
private static java.lang.String	url Holds the Database url on the form jdbc:subprotocol:subname.

Constructor Summary

private	DBConnection() An empty constructor, to override the constructor supplied by the compiler.
	DBConnection(DBConnection connection) A deep copy constructor.
private	DBConnection(java.lang.String driver, java.lang.String url) Creates a new instacne of DBconnection.

Method Summary

boolean	_startTransaction() Starts a new transaction
boolean	_stopTransaction(boolean isSuccessful) Stops the current transaction by either commiting or rolling it back.
static boolean	checkSqlConnection() Checks if there is a SQL Connection as default instance or not.
static DBConnection	CreateNewDBConnection(java.lang.String driver, java.lang.String url) Creates and returns a new DBConnection, that is different from the default instance and will not be considered the default instance.
static void	CreateSqlConnection()
OperationInfo	executeNonQuery(java.lang.String query) Executes the specified query and gets the number of rows affected.
OperationInfo	executeProcedure(java.lang.String procName, java.util.ArrayList procArguments) Executes the given stored procedure.
OperationInfo	executeReader(java.lang.String query) Executes the specified query and returns a DataTable representing the ResultSet.
static OperationInfo	executeScalar(java.lang.String query) Executes the specified query and returns the first column of the first row of the ResultSet.
java.lang.String	formulateArguments(java.util.ArrayList arguments)
static DBConnection	getDefaultInstance() Gets the default DBConnection.
static java.sql.Connection	getSqlConnection() Gets Sql Server DBConnection.
static void	setDefaultConnectionString(java.lang.String driver, java.lang.String url) Sets the connection string to be sued when a new connection is to be created.
boolean	startTransaction() Starts a new transaction
boolean	stopTransaction(boolean isSuccessful) Stops the current transaction by either commiting or rolling it back.

Methods inherited from class java.lang.Object

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

Field Detail

driver

private static java.lang.String driver

Holds the database driver that is used in assocaition with the database url to create a connection.

url

private static java.lang.String url

Holds the Database url on the form jdbc:subprotocol:subname.

instance

private static DBConnection instance

Holds the sole instace of DBConnection.

dbDriver

private java.lang.String dbDriver

Holds the database driver that is used in assocaition with the database url to create a connection.

dbUrl

private java.lang.String dbUrl

Holds the Database url on the form jdbc:subprotocol:subname.

connection

private java.sql.Connection connection

Holds the connection to be used by each method.

Sqlconnection

private static java.sql.Connection Sqlconnection

Constructor Detail

DBConnection

private DBConnection()

An empty constructor, to override the constructor supplied by the compiler.

DBConnection

private DBConnection(java.lang.String driver,
                     java.lang.String url)

Creates a new instacne of DBconnection.

Parameters:

driver - The database driver.

url - The database Url.

DBConnection

public DBConnection(DBConnection connection)

A deep copy constructor.

Parameters:

connection - The connection to .be copied.

Method Detail

setDefaultConnectionString

public static void setDefaultConnectionString(java.lang.String driver,
                                              java.lang.String url)

Sets the connection string to be sued when a new connection is to be created.

Parameters:

driver - The database driver.

url - The database Url.

checkSqlConnection

public static boolean checkSqlConnection()

Checks if there is a SQL Connection as default instance or not.

Returns:

true if there exist, false otherwise.

getSqlConnection

public static java.sql.Connection getSqlConnection()

Gets Sql Server DBConnection.

Returns:

The default DBConnection.

getDefaultInstance

public static DBConnection getDefaultInstance()

Gets the default DBConnection.

Returns:

The default DBConnection.

CreateSqlConnection

public static void CreateSqlConnection()

CreateNewDBConnection

public static DBConnection CreateNewDBConnection(java.lang.String driver,
                                                 java.lang.String url)

Creates and returns a new DBConnection, that is different from the default instance and will not be considered the default instance. The Object returned is totally independent from the default configuration and doesn't affect any static members of this class.

Parameters:

driver - The database driver.

url - The database Url.

Returns:

a new DBConnection instance.

executeReader

public OperationInfo executeReader(java.lang.String query)

Executes the specified query and returns a DataTable representing the ResultSet.

Parameters:

query - The query to be executed.

Returns:

An OperationInfo instance whose Result is a DataTable representing the ResultSet.

executeScalar

public static OperationInfo executeScalar(java.lang.String query)

Executes the specified query and returns the first column of the first row of the ResultSet.

Parameters:

query - The query to be executed.

Returns:

An OperationInfo instance whose Result is a object containing a single value.

executeNonQuery

public OperationInfo executeNonQuery(java.lang.String query)

Executes the specified query and gets the number of rows affected.

Parameters:

query - The query to be executed, likely an INSERT, UPDATE or DELETE query.

Returns:

An OperationInfo instance whose Result is an integer representing the number of rows affected.

executeProcedure

public OperationInfo executeProcedure(java.lang.String procName,
                                      java.util.ArrayList procArguments)

Executes the given stored procedure.

Parameters:

procName - The name of the stored procedure.

procArguments - The arguments of the stored proceure.

Returns:

An operation info that holds the result of the stored procedure.

formulateArguments

public java.lang.String formulateArguments(java.util.ArrayList arguments)

_startTransaction

public boolean _startTransaction()

Starts a new transaction

Returns:

A boolean indicating if the operation done successfully or not.

_stopTransaction

public boolean _stopTransaction(boolean isSuccessful)

Stops the current transaction by either commiting or rolling it back.

Parameters:

isSuccessful - Indicates whether the transaction should be committed or rolled back.

Returns:

A boolean indicating if the operation done successfully or not.

startTransaction

public boolean startTransaction()

Starts a new transaction

Returns:

A boolean indicating if the operation done successfully or not.

stopTransaction

public boolean stopTransaction(boolean isSuccessful)

Stops the current transaction by either commiting or rolling it back.

Parameters:

isSuccessful - Indicates whether the transaction should be committed or rolled back.

Returns:

A boolean indicating if the operation done successfully or not.