Check if the next array element is different from the current in Java

Answer 1

Looks okay to me, assuming that your array does not contain null values.

Answer 2

Why don't just iterate it in it's natural order, i mean you don't have to compare it with the next array, just compare it with the previous one.

Answer 3

If max_lines is equal to lines_array.length, then it will work perfectly fine. Just add a one-line comment to clarify things (although the name of the variable makes it pretty clear)

current_line + 1 >= maxLines makes sure you don't get an ArrayIndexOutOfBounds.

Perhaps it is worth noting that there must be no null entries in the array, otherwise you risk a NullPointerException. So in order not to clutter your code, you can make a private method:

private boolean itemsDiffer(String current, String next) {
    if (current == null && next == null {
        return false; // or true, if that's your semantics
    } else {
        return current == null || current.equalsIgnoreCase(next);
    }
}

And then have:

boolean nextLineIsDifferentOrThereIsNoNextLine =
     (current_line + 1 >= max_lines) ? true : 
        itemsDifferent(linesArray[current_line], linesArray[current_line + 1];