Nth occurence of character in string and get value

Question

I am using the below code to find the nth occurrence of , (comma) in the string. And once I get this, I need to get the value between this occurrence(nth) and next occurrence (n+1th occurrence)

Please let me know if I am going wrong somewhere.

 int ine=nthOccurence(line,18);  
         String strErrorCode=line.substring(ine,line.indexOf(",", ine+1));
String errorCode=strErrorCode.substring(1, strErrorCode.length());

The function

public static int nthOccurence(String strLine,int index)
  {

      char c=',';
            int pos = strLine.indexOf(c, index);
            while (index-- > 0 && pos != -1)
            {
                pos = strLine.indexOf(c, pos+1);
               // System.out.println("position is " +  pos);
            }
                return pos;
        }

Thanks.

I'm confused. What `String errorCode=strErrorCode.substring(1, strErrorCode.length());` is supposed to accomplish? — PM 77-1, Oct 09 '13 at 14:59
The string returned contains a - at the beginning. I need to remove it..Hence. — AngelsandDemons, Oct 09 '13 at 15:03
[`substring` with two `int` parameters](http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#substring(int, int)) uses the 1st (from) as inclusive and 2nd (to) as exclusive. Does it agree with your definition of "*between*"? — PM 77-1, Oct 09 '13 at 15:03
But is the code correct..I mean I am getting variable output..I am not able to bet on the index. — AngelsandDemons, Oct 09 '13 at 15:03

score 2 · Accepted Answer · answered Oct 09 '13 at 15:02

Here's an alternative approach, also more readable:

public static String getAt(String st, int pos) {
    String[] tokens = st.split(",");
    return tokens[pos-1];
}

public static void main(String[] args) {
    String st = "one,two,three,four";
    System.out.println(getAt(st, 1)); // prints "one"
    System.out.println(getAt(st, 2)); // prints "two"
    System.out.println(getAt(st, 3)); // prints "three"
}

score 2 · Answer 2 · answered Oct 09 '13 at 15:04

2

Something like this?

public static int nthOccurence(String strLine,int index){
  String[] items = strLine.split(",");
  if (items.length>=index)
      return items[index];
  else
      return "";//whatever you want to do it there's not enough commas
}

answered Oct 09 '13 at 15:04

tom

2,704
16
28

I'm not sure what you mean. Do you mean you need the position in the string? The start position, end position or both. Do you include the commas in that or not. You need to be more clear. – tom Oct 09 '13 at 15:14

Nth occurence of character in string and get value

2 Answers2