Converting string to int in java

Chardee MacDennis · 15-12-2005 07:19PM #1

does anyone know how to convert a string of value -42 ,for example, to an int. i cant seem to parse negative numbers stored as strings.

thanks

MrPinK · 15-12-2005 07:25PM

int num = Integer.parseInt(stringNum);

Chardee MacDennis · 15-12-2005 08:12PM

nope that wont work:

Exception in thread "main" java.lang.NumberFormatException: null

Hobbes · 15-12-2005 08:24PM

post your code.

Chardee MacDennis · 15-12-2005 08:52PM

excuse the stupid variable names - i was getting very board...

int[][] guvnor = new int[5][100];
String cheese;
int rabbite;
String delim = "-";
for(int nerves = 0; nerves < fancy.length; nerves++){
for(int megamac = 0; megamac < 100; megamac++){
cheese = pants[nerves][megamac];
rabbite = Integer.parseInt(cheese);
guvnor[nerves][megamac] = rabbite;
}
}

EOA_Mushy · 15-12-2005 08:53PM

Any change the input string turns out to be "-42"? because parse isnt going to figure out how "-" is a number....

Hobbes · 15-12-2005 09:07PM

What is "fancy" declared as?

Nothing there will ever be negative. Your null error message what line is that appearing on?

pH · 15-12-2005 09:29PM

parseInt() will handle a negative sign as the first char fine.

The current problem (Exception in thread "main" java.lang.NumberFormatException: null) is most likely caused by sending a null String to parseInt - parseInt(null)

An element of the pants[][] array (presumably String[][] ) is null

You are iterating thought the pants[][] array, but using bounds of fancy.length and 100 - Make sure these are correct!

Chardee MacDennis · 15-12-2005 09:58PM

nice one ph this makes sense so if i throw in an if statement saying it should do nothing if the value is null?

EDIT: yup this is working, thanks guys!!

Mutant_Fruit · 16-12-2005 01:52AM

I have to say one thing, and one thing only.

Kudos!

I've never seen such wonderfully named variables in my life!

BrokenArrows · 16-12-2005 07:59PM

i did that once for a fairly big program. All the names were all over the place. I left the project for about 3 weeks and when i came back to it i had no idea what anything was.

Took a while to sort out.

rsynnott · 20-12-2005 07:29PM

http://thedailyWTF.com, tbh

Converting string to int in java

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