Checking if two strings are permutations of each other

Question

How to determine if two strings are permutations of each other

Answer 1

If we do the initial length check, to determine if the two strings are of the same length or not,

    public boolean checkIfPermutation(String str1, String str2) {
      if(str1.length()!=str2.length()){
        return false;
      }
      int str1_sum = getSumOfChars(str1);
      int str2_sum = getSumOfChars(str2);
      if (str1_sum == str2_sum) {
        return true;
      }
      return false;
}

public int getSumOfChars(String str){
      int sum = 0; 
      for (int i = 0; i < str.length(); i++) {
        sum += str.charAt(i);
      }
      return sum;
}