How to convert String to long in Java?

public class StringToLong {

   public static void main (String[] args) {

      // String s = "fred";    // do this if you want an exception

      String s = "100";

      try {
         long l = Long.parseLong(s);
         System.out.println("long l = " + l);
      } catch (NumberFormatException nfe) {
         System.out.println("NumberFormatException: " + nfe.getMessage());
      }

   }
}

Use Long.parseLong()

 Long.parseLong("0", 10)        // returns 0L
 Long.parseLong("473", 10)      // returns 473L
 Long.parseLong("-0", 10)       // returns 0L
 Long.parseLong("-FF", 16)      // returns -255L
 Long.parseLong("1100110", 2)   // returns 102L
 Long.parseLong("99", 8)        // throws a NumberFormatException
 Long.parseLong("Hazelnut", 10) // throws a NumberFormatException
 Long.parseLong("Hazelnut", 36) // returns 1356099454469L
 Long.parseLong("999")          // returns 999L

To convert a String to a Long (object), use Long.valueOf(String s).longValue();

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