uk.ac.ic.doc.automed.util.db
Class DBAccess

java.lang.Object
  uk.ac.ic.doc.automed.util.db.DBAccess

Direct Known Subclasses:

DBEmbedded, DBPostgres

public abstract class DBAccess
extends java.lang.Object

Field Summary

protected java.util.Map	connections
protected java.lang.String	dbFQPath
protected java.lang.String	password
protected java.util.Properties	props
protected java.lang.String	user

Constructor Summary

DBAccess(java.lang.String dbFQPath, java.lang.String user, java.lang.String password, java.util.Properties props)
Creates a new instance of DBAccess

Method Summary

void	closeConnection()
abstract void	commit() Only use this method if you want to commit changes immediately.
protected void	executeCommand(java.lang.String cmd) Mostly used for executing control commands, e.g.
abstract java.sql.ResultSet	executeQuery(java.lang.String expression) This method is used for SELECT statement
abstract void	executeStatement(java.lang.String expression) This method is used for making changes to data, e.g.
abstract java.sql.Connection	getConnection()
java.util.Map	getCurrentRow(java.sql.ResultSet rs) Return current row in a result set as a HashMap of column->value.
boolean	isTableExist(java.lang.String name) Checks whether or not a table exists in the database
java.sql.Connection	newConnection() Creates a new connection to add to the pool
void	printResultSet(java.sql.ResultSet rs) A generic implementation of debug-print of a result set
abstract void	setAutoCommit(boolean autoCommit) Different data sources understands auto-commit differently.
void	shutdown() Shutdown in-process database, closes current connection to it

Methods inherited from class java.lang.Object

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

Field Detail

dbFQPath

protected java.lang.String dbFQPath

user

protected java.lang.String user

password

protected java.lang.String password

props

protected java.util.Properties props

connections

protected java.util.Map connections

Constructor Detail

DBAccess

public DBAccess(java.lang.String dbFQPath,
                java.lang.String user,
                java.lang.String password,
                java.util.Properties props)

Creates a new instance of DBAccess

Method Detail

newConnection

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

Creates a new connection to add to the pool

Throws:

java.sql.SQLException

getConnection

public abstract java.sql.Connection getConnection()

closeConnection

public void closeConnection()

shutdown

public void shutdown()
              throws java.sql.SQLException

Shutdown in-process database, closes current connection to it

Throws:

java.sql.SQLException

setAutoCommit

public abstract void setAutoCommit(boolean autoCommit)
                            throws java.sql.SQLException

Different data sources understands auto-commit differently. This method
tries to encapsulate the operation to set auto-commit

Parameters:

autoCommit - a boolean value: true = auto-commit; false otherwise

Throws:

java.sql.SQLException

commit

public abstract void commit()
                     throws java.sql.SQLException

Only use this method if you want to commit changes immediately.

Throws:

java.sql.SQLException

isTableExist

public boolean isTableExist(java.lang.String name)
                     throws java.sql.SQLException

Checks whether or not a table exists in the database

Throws:

java.sql.SQLException

getCurrentRow

public java.util.Map getCurrentRow(java.sql.ResultSet rs)
                            throws java.sql.SQLException

Return current row in a result set as a HashMap of column->value.

Throws:

java.sql.SQLException

printResultSet

public void printResultSet(java.sql.ResultSet rs)
                    throws java.sql.SQLException

A generic implementation of debug-print of a result set

Throws:

java.sql.SQLException

executeQuery

public abstract java.sql.ResultSet executeQuery(java.lang.String expression)
                                         throws java.sql.SQLException

This method is used for SELECT statement

Parameters:

expression - is an SQL statement to use

Returns:

ResultSet object of the result data

Throws:

java.sql.SQLException

executeStatement

public abstract void executeStatement(java.lang.String expression)
                               throws java.sql.SQLException

This method is used for making changes to data, e.g. INSERT, DELETE, UPDATE

Parameters:

expression - is an SQL statement to use

Throws:

java.sql.SQLException

executeCommand

protected void executeCommand(java.lang.String cmd)
                       throws java.sql.SQLException

Mostly used for executing control commands, e.g. SHUTDOWN, SET ...

Parameters:

cmd - the command to execute

Throws:

java.sql.SQLException