StringTokeniser not reading data

I've to read data from a file and I've just entered some sample data as a String in StringTokenizer. I can't understand what is wrong with my code here. Can someone please advise?

import java.util.StringTokenizer;

public class rough {

    public static void main(String[] args) throws Exception {
        StringTokenizer itr = new StringTokenizer("PKE2324 02-12-2020 200"
      + "\nMJD432 19-05-2019 150");

        while (itr.hasMoreTokens()){
            String line = itr.nextToken().toString();
            String[] tokens = line.split(" ");
            String[] date = tokens[1].split("-");
            String yr = date[2];
            String reg = tokens[0];
            String regy = new String(reg + " " + yr);
            System.out.println(regy);   
            }
     }

}

I want to get the registration number and year as a String. When I run this, I keep getting ArrayIndexOutofBounds

This is the type of runtime error which has been caused due to logical error and inappropriate delimeter.

Assuming you want to tokenise the big string using newline character, use, \n as delimeter to StringTokenizer.

Have a look at the corrected code below which satisfies your use case:

import java.util.StringTokenizer;

public class rough {

    public static void main(String[] args) throws Exception {
        StringTokenizer itr = new StringTokenizer("PKE2324 02-12-2020 200"
    + "\nMJD432 19-05-2019 150", "\n");

        while (itr.hasMoreTokens()){
            String line = itr.nextToken().toString();
            String[] tokens = line.split(" ");
            String[] date = tokens[1].split("-");
            String yr = date[2];
            String reg = tokens[0];
            String regy = new String(reg + " " + yr);
            System.out.println(regy);   
            }
    }
}

Output:

PKE2324 2020
MJD432 2019

Exception caused by this line

String[] tokens = line.split(" ");
String[] date = tokens[1].split("-");

line = PKE2324, so tokens[] = { "PKE2324" } --> length = 1
tokens[1] --> ArrayIndexOutOfBoundException

To fix this:

StringTokenizer itr = new StringTokenizer("PKE2324 02-12-2020 200"
      + "\nMJD432 19-05-2019 150");

Default delimeter is whitespace.
You should pass delimeter in constructor if you want different delimeter.