How do I make a method where I check certain values in an array rather than the whole array?

Question

I have created method which checks an entire array and retrieves the string which comes latest alphabetically. What I am trying to do now is to change that method so that the user enters 2 positions in the array and for the method to return the value that comes latest between the 2. eg if I have a string of arrays which say, {"Bob", "Michael", "Joe", "Gazza", "Paul", "Barry"} , and I call the method getMaxsValue(array,0,1) . it should output the name "Michael" .

Here is the method getMaxsValue:

public static String getMaxsValue(String[] array, int pos1, int pos2) {
    String longstr = array[0];
    for (String s : array) {
        if (s.compareTo(longstr) > 0) {
            longstr = s;
        }
    }
    return longstr;
}

Answer 1

Instead of a for-each loop you should only loop between the given indices.

public static String getMaxsValue(String[] array, int pos1, int pos2) {
    String longstr = array[pos1];
    for (int i = pos1; i <= pos2; i++) {
        if (array[i].compareTo(longstr) > 0) {
            longstr = array[i];
        }
    }
    return longstr;
}

As GameDroids pointed out it might be a good idea to add a validation of the given positions at the beginning of your function ie

if(pos1 > pos2 || pos1 < 0 || pos2 >= array.length){
    //throw some exception
}

If you only want to compare the values at the two given indices that would be something like this

public static String getMaxsValue(String[] array, int pos1, int pos2) {
    if (array[pos1].compareTo(array[pos2]) > 0) {
            return array[pos1];
    }
    return array[pos2];
}

Answer 2

For the stream enthusiasts here is an alternative

public static String getMaxsValue(String[] array, int pos1, int pos2) {
    return Arrays.stream(array,pos1,pos2 +1).max(String::compareTo).orElse(null);
}

The check for the indices comment from @GameDroids applys here as well.