Bug 199021 Error message pops up several times when click an invalid dataset
Description: There is a sqlserver datasource and dataset, remove the jtds driver to let the dataset invalid. Double click on the dataset, the error message will pop up serveral times. Build version:2.2.0.v20070807-0630 Steps to reproduce: 1. Create a sqlserver datasource and dataset. 2. Remove the jtds driver, and the dataset will be invalid. 3. Double click on the dataset. Expect result: Error message pops up once to indicate the problem. Actual result: Error message pops up serveral times.
data/org.eclipse.birt.report.data.oda.jdbc.ui/src/org/eclipse/birt/report/data/oda/jdbc/ui/editors/SQLDataSetEditorPage.java
cachedSearchTxt = searchTxt.getText( );
		namePattern = SQLUtility.getTailoredSearchText( searchTxt.getText( ) );
		String dbtype = getSelectedDbType( );
		cachedDbType = dbtype;
		if ( dbtype != null )
		{
			if ( DbType.TABLE_STRING.equalsIgnoreCase( dbtype )
					|| DbType.VIEW_STRING.equalsIgnoreCase( dbtype ) )
			{
				tableType = new String[]{
					dbtype
				};
			}
		}
		String catalogName = metaDataProvider.getCatalog( );
		ArrayList tableList = new ArrayList( );
		ResultSet tablesRs = null;
		ArrayList procedureRs = null;
		if ( schemaName != null && schemaName.trim( ).length( ) > 0 )
		{
			
			{
				if ( metaDataProvider.isProcedureSupported( ) )
					procedureRs = metaDataProvider.getAllProcedure( catalogName,
							schemaName,
							namePattern );
				if ( !DbType.PROCEDURE_STRING.equalsIgnoreCase( dbtype ) )
					tablesRs = metaDataProvider.getAlltables( catalogName,
							schemaName,
							namePattern,