Comple errors using JOptionPane

Question

I'm trying to write a Java program using JOptionPane dialog/display boxes that reads an integer and checks whether it is even using true/false statements. I also want the program must check if the number the user entered is between 1 and 1000.
I haven't found alot of help in the book I have and i've found some help in another forum but it doesn't seem to compile well, I get the following errors:
IntegerRead.java:39: cannot find symbol
symbol : method valueOf(java.lang.String)
location: class Integer
int number = Integer.valueOf(s);
^
Integer.java:13: cannot find symbol
symbol : class Scanner
location: class Integer
Scanner input = new Scanner( System.in );
^
Integer.java:13: cannot find symbol
symbol : class Scanner
location: class Integer
Scanner input = new Scanner( System.in );
Here is the code:
// Assignment 2.1: IntegerRead.java
// This program reads an integer, checks if it's even and is between 1 and 1000.
import javax.swing.JOptionPane; // program uses class JOptionPane
public class IntegerRead
public static boolean isNumber(String args)
if(args.length() > 3)
throw new IllegalArgumentException("Invalid argument");
else
boolean isNumber = false;
for(int i = 0; i < args.length(); i++)
char c = args.charAt(i);
if(Character.isDigit(c))
isNumber = true;
else
isNumber = false;
return isNumber;
public static boolean isEven(int aNumber)
int a = aNumber & 1;
return (a == 0);
public static void main(String args[])
String s = JOptionPane.showInputDialog("Please enter number between 0 to 999");
System.out.println("Is Number " + isNumber(s));
if(isNumber(s))
int number = Integer.valueOf(s);
System.out.println("Number " + number + "is Even " + isEven(number));
for(int i = 0; i < 999; i++)
System.out.println(i + " is " + isEven(i));
I know i'm missing very simple. I'm new and have tried to build upon what I have so far, but I can't figure it out.
Thanks....
Edited by: Scott.Dishman on Jul 9, 2008 4:07 PM

Answer 1

You have a class named Integer somewhere on your class path. Get rid of it or rename it. If you've already renamed your Integer.java file, you still need to delete the Integer.class file. You should never create your own class that has the same name as a class in the standard java.lang package.