Converting the comma seprated numeric string into int array //convert the comma separated numeric string into the  array of int. 
public class HelloWorld 
{
  public static void main(String[] args)
   {
     // line is the input  which have the comma separated number
     String line = "1,2,3,1,2,2,1,2,3,";
     // 1 &gt; split   
     String[] inputNumber =  line.split(",");
    // 1.1 &gt; declear int array
     int number []= new int[10];
     // 2 &gt; convert the String into  int  and save it in int array.
 for(int i=0; i&lt;inputNumber.length;i++){
       number[i]=Integer.parseInt(inputNumber[i]);
  }
 }

}


Is there a more efficient solution to achieve the same result?
Basic improvements


Instead of setting the size of the int array to 10, it would be better to derive the right size from the size of String array
Instead of int number[] the more conventional way to write is int[] number
For structures that contain multiple values it's more natural to give plural names, for example "number" -> "numbers" for an array of numbers
The variable names are very poor in general, and should be improved to better reflect their purpose, making the code easier to understand


Something like this:

String line = "1,2,3,1,2,2,1,2,3,";
String[] parts = line.split(",");
int[] ints = new int[parts.length];
for (int i = 0; i &lt; parts.length; i++) {
    ints[i] = Integer.parseInt(parts[i]);
}


Split to logical steps

It's good to get into the habit of decomposing tasks to their small steps. That is, instead of having all the logical steps in a single main method, it would be better to split to multiple functions, for example:

static int[] toIntArray(String[] arr) {
    int[] ints = new int[arr.length];
    for (int i = 0; i &lt; arr.length; i++) {
        ints[i] = Integer.parseInt(arr[i]);
    }
    return ints;
}

static int[] parseLineToIntArray(String line) {
    return toIntArray(line.split(","));
}

public static void main(String[] args) {
    String line = "1,2,3,1,2,2,1,2,3,";
    System.out.println(Arrays.toString(parseLineToIntArray(line)));
}