code: static public WorkSheet unionWorkSheetsRowJoin(String w1FileName, String w2FileName, char delimitter, boolean secondSheetMetaData) throws Exception {
  		WorkSheet w1 = WorkSheet.readCSV(w1FileName, delimitter);
  		WorkSheet w2 = WorkSheet.readCSV(w2FileName, delimitter);
  		return unionWorkSheetsRowJoin(w1, w2, secondSheetMetaData);
  
  	}
docs: Combine two work sheets where you join based on rows. Rows that are found
  in one but not the other are removed. If the second sheet is meta data
  then a meta data column will be added between the two joined columns
  
  @param w1FileName
  @param w2FileName
  @param delimitter
  @param secondSheetMetaData
  @return
  @throws Exception