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
String tableName = tablesRs.getString( "TABLE_NAME" );
							String type = tablesRs.getString( "TABLE_TYPE" );
							if ( type.equalsIgnoreCase( "SYSTEM TABLE" ) )
								continue;
							int dbType = DbObject.TABLE_TYPE;
							if ( type.equalsIgnoreCase( "TABLE" ) )
							{
								image = tableImage;
								dbType = DbObject.TABLE_TYPE;
							}
							else if ( type.equalsIgnoreCase( "VIEW" ) )
							{
								image = viewImage;
								dbType = DbObject.VIEW_TYPE;
							}
							DbObject dbObject = new DbObject( getTableNameWithSchema( schemaName,
									tableName ),
									tableName,
									dbType,
									image );
							tableList.add( dbObject );
							count++;
						}
					}
					if ( needToCreateProcedureNode( dbtype, procedureRs ) )
					{