errorMessage.append(System.getProperty("line.separator"));
errorMessage.append(System.getProperty("n"));
errorMessage.append(System.getProperty("rn"));
errorMessage.append(System.getProperty("line.separator"));

public String getIDs(HashMap<String,List<Integer>> errorMap ){
    StringBuilder errorMessage = new StringBuilder();

    for (String state:errorMap.keySet()){

        List<Integer> listofId = errorMap.get(state);

        if (listofId){
            StringBuilder listOfIds = new StringBuilder();
            for (Integer id :listofId) {
                listOfIds.append(id.toString()+' , ')
            }
            errorMessage.append(state +" Trades: " +listOfIds.toString())
            errorMessage.append("n")
        }
    }
    return errorMessage.toString();
}