converting a string to an integer returns a nullPointerException

Question

I am trying to convert a string to an integer but in case it's not possible.

I want that integer variable to have a null value but I keep on getting a null pointer exception when the string is unconvertable while I need it in such case to catch the exception and handle it the way i want which is to put null in the integer variable.

This is my code:

String numt=request.getParameter("telephoneClient");
Integer tel;
try{
    tel=Integer.parseInt(numt);
} catch(NullPointerException ex1)
{
    tel=null;
} catch (NumberFormatException ex2) 
{
    tel=null;
} catch(Exception ex)
{
    tel=null;
}

Your servlet couldn't handle the that parameter so your front end is not sending it properly — Basil Battikhi, Jul 05 '18 at 15:23
Post your stack trace and point out the exact line throwing NPE. Without that it would just be guesswork. — Shanu Gupta, Jul 05 '18 at 15:28
Guess: `request` is `null`. Or `tel` will be converted to an `int`. Or... `getParameter(String)` throws a `NullPointerException`. - Stacktrace or it didn't happen. — Johannes Kuhn, Jul 05 '18 at 15:38
i don t think so because i ve tried it with a float and it functions well — Chaima Trabelsi, Jul 05 '18 at 21:11

score -1 · Answer 1 · answered Jul 05 '18 at 15:26

-1

For more information on errors from INteger.parseInt check out this question. To get around a NPE You can do a null check on numt before attempting to parse to Integer.

String numt=request.getParameter("telephoneClient");
Integer tel;
if(null ==numt){
  tel = numt;
  return tel;
}
else{
    try{
        tel=Integer.parseInt(numt);
    } catch(NullPointerException ex1)
    {
        tel=null;
    } catch (NumberFormatException ex2) 
    {
        tel=null;
    } catch(Exception ex)
    {
        tel=null;
    }
}

Added A null check before your try block. if null, tel = null, and return

answered Jul 05 '18 at 15:26

Akin Okegbile

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where is the more information ? and this is will not even compile – Basil Battikhi Jul 05 '18 at 15:58
Click the link for your first question? Will the questions code compile? – Akin Okegbile Jul 06 '18 at 05:07

converting a string to an integer returns a nullPointerException

1 Answers1