NumberFormatException: Invalid int even if it is really an integer

Question

I encounter some problems parsing a string into integer, I don't know what the problem is.

I am passing a string with an integer value to my function to check if it would be parseable.

This is my function.

private boolean isNumeric (String value){
        try {
            System.out.println("VALUE = " +value);
            int x = Integer.parseInt(value);
            return true;
        } catch (NumberFormatException e) {
            System.out.println("NumberFormatException: " + e.getMessage());
            return false;
        }
    }

I checked it by printing into the console. here is the result.

I/System.out: VALUE = 77
    NumberFormatException: Invalid int: "77"

Can you guys help me figure out what is wrong here. Cause I cannot convert this string into an integer.

To prove Andy's intuition try and print `value.length()`. If it is more than 2 he's right. — Federico klez Culloca, Jun 11 '20 at 07:19
no sir, it's just numbers, as you can see in the result, I printed it to check for additional characters, but there is none. — Reno Roy Sorima, Jun 11 '20 at 07:20
@renoroysorima what part of *non-printable* makes you think that printing would show them? :) — Federico klez Culloca, Jun 11 '20 at 07:21
@renoroysorima "as you can see" printing a string with non-printable characters won't show you the non-printable characters. — Andy Turner, Jun 11 '20 at 07:21
This code works fine when passed "77". Your problem isn't reproducible. — Giorgi Tsiklauri, Jun 11 '20 at 07:23
@GiorgiTsiklauri it's probably because that's not the value he's passing. — Stultuske, Jun 11 '20 at 07:24
Then he might want to debug and print whatever he's passing first. — Giorgi Tsiklauri, Jun 11 '20 at 07:24
@FedericoklezCulloca the lenght becomes 3. if so, what is the best way to remove it ? — Reno Roy Sorima, Jun 11 '20 at 07:24
Try to print each character of the input string and see it yourself. — Giorgi Tsiklauri, Jun 11 '20 at 07:25
@renoroysorima you can remove [everything but the digits](https://stackoverflow.com/a/40618873/133203) (adapt that by ignoring the part that accepts decimal separators, for your case). But you may want to discover why there's a non-printable character in that string to begin with. I suppose that string comes from an external source? — Federico klez Culloca, Jun 11 '20 at 07:27
@GiorgiTsiklauri that won't really help with non printable characters. — Stultuske, Jun 11 '20 at 07:29
I already figured it out, Thanks to @KremKlatt. all I needed is to trim the non visible white space. Thank you for you answers guys, it really helps me a lot. — Reno Roy Sorima, Jun 11 '20 at 07:31

score 1 · Accepted Answer · answered Jun 11 '20 at 07:21

1

You could try this as this will trim out all whitespaces from your input:

private boolean isNumeric (String value){
        try {
            System.out.println("VALUE = " +value);
            int x = Integer.parseInt(value.trim());
            return true;
        } catch (NumberFormatException e) {
            System.out.println("NumberFormatException: " + e.getMessage());
            return false;
        }
    }

parseInt() should return a NumberFormatException if the string is not parseable, but "77" should be. You should therefore try to trim it before you parse it to an int, maybe that would help.

answered Jun 11 '20 at 07:21

Klatten

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3
16

1

Thanks bro. There was a non visible white space in this strings. so I needed to trim those white spaces to make it a number. – Reno Roy Sorima Jun 11 '20 at 07:32
No problem, glad to help! :) – Klatten Jun 11 '20 at 07:33

NumberFormatException: Invalid int even if it is really an integer

1 Answers1