Value in TextField throws java.lang.NumberFormatException error

Question

So this is how I have my code (of course, not finished because I don't want to do any other work until I can figure out why I'm getting the error). It compiles no problem but when I try to run it I get a java.lang.NumberFormatException for my first line, not really sure why?

 if (Integer.parseInt(subtotalTextField.getText()) <= 200)
 {
    discountTextField.setText("2");
 }
    else
 {
 }

Trim that string before parsing it. Then all NFE's after that are due to user (input) error. — Perception, Dec 01 '12 at 03:10

score 4 · Answer 1 · answered Dec 01 '12 at 02:12

4

Because subtotalTextField.getText() returns something that is not parsable to int, in exception message it should show what was the value that was passed to parseInt()

answered Dec 01 '12 at 02:12

jmj

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score 0 · Answer 2 · answered Dec 01 '12 at 02:13

0

What's returned is not a String perhaps? Don't chain it, check for null and do

Object val = subtotalTextField.getText();
if (val != null)
    String txt = val.toString();

answered Dec 01 '12 at 02:13

Bostone

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It must be a string otherwise there would be a compile-time error (and `getText` usually means string). `NumberFormatException`s usually indicate that a string can't be parsed as an int (or other numeric type). – arshajii Dec 01 '12 at 02:17
It is a string, but not an integer representation – AlexWien Dec 01 '12 at 02:17
Not in Android for example - there it will return Spannable – Bostone Dec 01 '12 at 04:46

score 0 · Answer 3 · answered Dec 01 '12 at 02:17

As stated, the text entered in the textfield can't be parsed to an Integer. This means that your textfield contains characters i.e. "2s" .

if you want to avoid this error everytime an user enters a non-valid Integer, surround it with a try-catch clause.

try{
// Try to parse to Integer

}catch(NumberFormatException e) {
// Thing to do when a user enters non-valid Integer
}

score 0 · Answer 4 · answered Dec 01 '12 at 02:58

Possible value for subtotalTextField.getText() that I can think about it

 subtotalTextField.getText() = null; // or

 subtotalTextField.getText() = "";  // or

 subtotalTextField.getText() = "Any non passable String"; // a ,b c .. 1a ,2a ... etc

If you could make sure user is entered value is valid number by any validation. No problem start with your logic.

Value in TextField throws java.lang.NumberFormatException error

4 Answers4