Please help me debug this program. I am stuck on fixing the line :

if(str.charAt(x) == " ")

// Program prompts user to enter a series of integers // separated by spaces // Program converts them to numbers and sums them import java.util.*; public class FixDebugSeven2 { public static void main(String[] args) { String str; int x; int length; int start = 0; int num; int lastSpace = -1; int sum = 0; String partStr; Scanner in = new Scanner(System.in); System.out.print("Enter a series of integers separated by spaces >> "); str = in.nextLine(); length = str.length(); for(x = 0; x <= length; ++x) { if(str.charAt(x) == " ") //I am having trouble figuring out how to debug this line { partStr = str.substring(x, lastSpace + 1); num = Integer.parseInt(partStr); System.out.println(" " + num); sum = num; lastSpace = x; } } partStr = str.substring(lastSpace + 1, length); num = Integer.parseInt(partStr); System.out.println(" " + num); sum = num; System.out.println(" -------------------" + " The sum of the integers is " + sum); } }