Integer.parseInt() NumberFormatException

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May 29th, 2005, 11:23 AM

station

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Integer.parseInt() NumberFormatException

I'm having trouble using Integer.parseInt(), it's giving me a NumberFormatException, etc. This code is suppose to read the user input and put it in a string, then parse the integer from the string. Not sure what the problem is, here is my code. Can someone tell me what's wrong with it?

Code:

import java.util.Scanner;

public class Driver
{
public static void main(String[]args)
{

Scanner scan = new Scanner(System.in);

System.out.println("Key in sentence with number");
String first = scan.next();

System.out.println("Key in sentence with number");
String sec = scan.next();

int a = Integer.parseInt(first);
int b = Integer.parseInt(sec);

System.out.println("sum is " + (a + b));

}
}

//end of program

this is the output

Key in sentence with number
this number is 1
Key in sentence with number
Exception in thread "main" java.lang.NumberFormatException: For input string: "this"
at java.lang.NumberFormatException.forInputString(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)

May 29th, 2005, 01:18 PM

tfecw

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Hmm, well NUmberFormatExceptions are thrown when your string is something other then a number. IF you do something like Integer.parseInt("FOO"), it will throw the excpetion.

That being said. I copy and pased your code and it seems to work fine. Instead of typing "This number is 1" when prompted for input. Type in only numbers.

May 29th, 2005, 02:23 PM

station

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Quote:

Originally Posted by tfecw

but isn't the Integer.parseInt(String str) suppose to take a string as a parameter then get the integer out?

May 31st, 2005, 03:33 PM

Rebel103

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It will take a string or name parameter that has a numeric value and convert it to the numeric value. When you are inputing values from the keyboard as you are above as strings it still must be something that can be converted to an int, i.e. "12". Which is why tfcew told you to just input numbers and the code works.
Example:
HTML Parameter: <param name="UserID" value="1">
Java String to Int: int x=Integer.parseInt(getParameter("UserID")); // value will = 1

Here is something that may help you understand: http://www.javaworld.com/javaworld/jw-10-2002/jw-1004-java101.html

May 31st, 2005, 06:54 PM

station

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Quote:

Originally Posted by Rebel103

okay thanks i got it now

Integer.parseInt() NumberFormatException

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