Bug 211004 Failed to remove temp db directory after running multiple reports
Description: I use Report Engine API to do runAndrender, run and dataextract tasks on multiple reports. Before the Platform started, I change the temp folder(System.setProperty( "java.io.tmpdir", TEMP_HOME )). Each task is closed after it finished and I shutdown the Platform after all the tasks finished. In log I found "Fail to remove one or more file in temp db directory,but it will be removed when the VM exits: D:\BIRT_NG\temp/BIRTSampleDB_1196129572031_10a6ae2". In temp folder the BIRTSampleDB_XXX is still here but not removed. I think it is the issue when remove the Temp sampleDB. Build number: 2.3.0.v20071127-0630
data/org.eclipse.birt.report.data.oda.jdbc/src/org/eclipse/birt/report/data/oda/jdbc/JDBCDriverManager.java
"JDBCDriverManager starts up" );
	}
	
	public synchronized static JDBCDriverManager getInstance()
	{
		if ( instance == null )
			instance = new JDBCDriverManager();
		return instance;
	}
	
	/**
	 * Gets a JDBC connection 
	 * @param driverClass Class name of JDBC driver
	 * @param url Connection URL
	 * @param connectionProperties Properties for establising connection
	 * @return new JDBC Connection
	 * @throws SQLException
	 */
	public Connection getConnection( String driverClass, String url, 
			Properties connectionProperties, String driverClassPath ) throws SQLException, OdaException
	{
        validateConnectionUrl( url,null );
		if ( logger.isLoggable( Level.FINE ))
			logger.fine("Request JDBC Connection: driverClass=" + 
					(driverClass == null? "" : driverClass) + "; url=" + url);
		return doConnect( driverClass, url, null, connectionProperties, driverClassPath );
	}
	/**
	 * Gets a JDBC connection 
	 * @param driverClass Class name of JDBC driver