Write a method that checks if there is at least on pair of numbers which sum equals target

public Boolean sumsToTarget(Integer[] arr, Integer target) {
 Map<Integer, Integer> numMap = new HashMap<>();
  for (int i = 0; i < arr.length; i++) {
    int complement = target - arr[i];
    if (numMap.containsKey(complement)) {
      return true;
    } else {
      numMap.put(arr[i], i);
    }
  }
return false;
}