How to iterate over a map to get all the values for 2 keys

Question

I have read csv and stored the values in map (key-value format) I need to fetch all values for 2 particular key into an array list to comapre it with database values columns

ArrayList ftlVal = new ArrayList<>();

                for (Map<String, String> map : finResult) {
                      Object[] key = {"Column2", "Column6"};
                      for (int i = 0; i < key.length; i++) {
                             do {
                                   //for (int j = 0; j <key.length; j++) {
                                          //while (map.get(key[j]) != null) {
                                                Object value = map.get(key[i]);
                                                // System.out.println(value);

                                                if (!ftlVal.contains(value)) {
                                                       ftlVal.add((String) value);
                                                       System.out.println(ftlVal);
                                                       i++;
                                                }
                                          }while (map.containsKey(key[i]));
                                   }
                             }
                             // System.out.println(finResult);
                      //}
                //}

I need all the values for column2 and column6 in an arrylist and then to compare those columns with database column2 and column6

Answer 1

Keeping aside how you compare the ArrayLists with the database columns, the following code will give you the two ArrayLists that you need.

ArrayList<String> column2List = new ArrayList<>();
ArrayList<String> column6List = new ArrayList<>();
for (Map<String, String> map : finResult) {
  String column2Value = map.get("Column2", null);
  String column6Value = map.get("Column6", null);
  column2List.add(column2Value);
  column6List.add(column6Value);
}

The and are the two ArrayLists that you need. 和是您需要的两个ArrayLists。