Substring of string seperated by commas

Question

Hi All,
I am trying for a logic that i have some emp ids as a string seperated by commas and i need the substring of emp ids as below.
Can any one help in splitting the string as below.
public static void main(String args[]) {
         String empId = "1,2,3,4,5,6,7,8,9,10";
        int i;
           int count = 9;
           for (i = 0; i <= count; i = i + 3)
             System.out.println("Emp IDs are : " +empId);
              Result is:
Emp IDs are : 1,2,3,4,5,6,7,8,9,10
Emp IDs are : 1,2,3,4,5,6,7,8,9,10
Emp IDs are : 1,2,3,4,5,6,7,8,9,10
Emp IDs are : 1,2,3,4,5,6,7,8,9,10
But i want the result like:
Emp IDs are : 1,2,3
Emp IDs are : 4,5,6
Emp IDs are : 7,8,9
Emp IDs are : 10
thanks for your help.

Answer 1

It can be helpfull to split the question into smaller pieces.
How many id's do you have. When you have the complete String use
//put the string in an array
String[] stringToArray = longIdString.split(",");
//How any id's
int numberOfIdInArray = stringToArray.length;'
Now you know the number of id's.
Divide the number by 5 and you know the number of id's in one new line
Then make 2 loops. For 5 times add the original string with a begin and endpoint in a new string.
package test;
public class SplitString {
  public static void main(String[] args) {
  //the initial id's
  int numberOfIds = 5000;
  final int NUMBEROFLINES = 5;
  //Make a long string
  String longIdString = "";
  StringBuilder builder = new StringBuilder();
  for(int i = 1; i <= numberOfIds; i++){
  builder.append(i + ",");
  longIdString = builder.toString();
  System.out.println("Original Array: " + longIdString);
  //put the string in an array
  String[] OriginalArray = longIdString.split(",");
  //How any id's
  int numberOfIdInOriginalArray = OriginalArray.length;
  System.out.println("Number of Id's: " +numberOfIdInOriginalArray);
  //Number of id's in one row
  int numberOfIdInOneRow = numberOfIdInOriginalArray / NUMBEROFLINES;
  System.out.println("Id's in one row: " + numberOfIdInOneRow);
  //Make 5 strings and put them in a new array
  String[] theNewStrings = new String[NUMBEROFLINES]; //Aray where you can store the new Strings
  int startpoint = 0;
  int endpoint = startpoint + (numberOfIdInOneRow);
  for(int i = 0; i < NUMBEROFLINES; i++){
  StringBuilder buildNewString = new StringBuilder();
  for (int j = startpoint; j < endpoint; j++){
  //Remember that the first value in an array is at index 0
  buildNewString.append(OriginalArray[j] + ",");
  theNewStrings[i] = buildNewString.toString();
  //Create a new start and endpoint for the next String
  startpoint = startpoint + numberOfIdInOneRow;
  endpoint = startpoint + (numberOfIdInOneRow);
  //Print the new 5 strings
  for(int i = 0; i < theNewStrings.length; i++){
  System.out.println(theNewStrings[i].toString());
In the "real world" you have to program the rounding of the division.