value in hashmap a not exist in hashmap b
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That's my question on the title, i have two differents hashmaps with query results, though the 2 hashmaps are diferent sizes hashmap, and im trying to find records that doesn't exists on hashmap b, i'll post my code so far, i did the comparition via sql i get the result i want but when i tried to put it in code i, not a success.  I hope you can orient me, and thanks in advance

    HashMap<Integer, HashMap<String, Object>> mapA = new HashMap<>();
    HashMap<Integer, HashMap<String, Object>> mapB = new HashMap<>(); 

    int m=0;
            
            for (int j = 0; j < mapA.size(); j++) {
                for (int k = 0; k < mapB.size(); k++) {                    if(!mapA.get(j).get("folio").toString().equals(mapB.get(k).get("folio").toString())){
                        m++; // count many records not exist on mapB
                    }
                }
            }
            System.out.println(m);     