Using Substring and indexOf

We can use .substring(start,end) to copy part of a String.

We can use indexOf( String ) to find a small String in a larger one.

Assume that name contains  "Jones, Fred"  or some other name,
in the format  "Last, First". 

Write a method that accepts name as a parameter,
uses indexOf to locate the comma, then uses substring
to copy the first name that is following the comma.
Notice that there is also a blank space after the comma.

Solution

public  String  firstName(String name)
{
     int  c  =  name.indexOf(",");    // position of the comma

     String first =  name.substring( c + 1 , name.length() );
     
     return  first;

}