Thread: cannot find symbol

i have programmed two programs and both of them when compiled highlighted the same error:Scanner ob=new Scanner(System.in);.saying cannot find symbol

void input()
{
Scanner ob=new Scanner(System.in);
System.out.print("Enter the first number:");
x=ob.nextInt();
System.out.println("Enter second number:");
y=ob.nextInt();
}

umm...oh yes.it just slipped off from my mind...thanks

--- Update ---

but now again it says can't find symbol.."ch=ob.nextInt();"


int ch;
do
{

System.out.println("Press 1:ADDITION");
System.out.println("Press 2:SUBTRACTION");
System.out.println("Press 3:MULTIPLICATION");
System.out.println("Press 4IVISION");

System.out.println("ENTER YOUR CHOICE:");
ch=ob.nextInt();

you have to import java.util.Scanner;
then code runs well

Originally Posted by akymcs

you have to import java.util.Scanner;
then code runs well

How do you know this? For all we know, his ob variable could be local to a block and not visible from where he's trying to use it. I second Norm's recommendation that we get more complete information before we start shooting from the hip.

Originally Posted by curmudgeon

How do you know this? For all we know, his ob variable could be local to a block and not visible from where he's trying to use it. I second Norm's recommendation that we get more complete information before we start shooting from the hip.

i wrote for this..
error:Scanner ob=new Scanner(System.in);.saying cannot find symbol

now the next what hi say can not find symbol it will require complete code...

sorry for this.here's the code:

import java.util.*;
class calculator
{
int x,y,result;
{
x=0;
y=0;
result=0;

}
void input()
{

Scanner ob=new Scanner(System.in);
System.out.print("Enter the first number:");
x=ob.nextInt();
System.out.println("Enter second number:");
y=ob.nextInt();
}

void sum()
{
result=x+y;
}
void sub()
{
result=x-y;
}

void mult()
{
result=x*y;
}

void div()
{
result=x/y;
}

void display()
{
System.out.println("Sum of the numbers:"+result);
System.out.println("Difference between the numbers:"+result);
System.out.println("product of the numbers:"+result);
System.out.println("division of the numbers:"+result);
}
class main
{

public static void main(String args[])
{
calculator ob=new calculator();
int ch;
do
{

System.out.println("Press 1:ADDITION");
System.out.println("Press 2:SUBTRACTION");
System.out.println("Press 3:MULTIPLICATION");
System.out.println("Press 4IVISION");

System.out.println("ENTER THE CHOICE:");
ch=ob.nextInt();
if(ch==1)
{
ob.input();
ob.sum();
ob.display();
}

if(ch==2)
{
ob.input();
ob.sub();
ob.display();
}
if(ch==3)
{
ob.input();
ob.mult();
ob.display();
}
if(ch==4)
{
ob.input();
ob.div();
ob.display();
}

System.out.println("ENTER THE CHOICE:");
ch=ob.nextInt();
}
while(n<5);
}
}
}

In the class main:
ch=ob.nextInt();
ob is a calculator object and don't recognize the methode nextInt() who belongs to a Scanner object.

while(n<5);
the variabele n is not declared in the main class.

ATIBA nextInt is method of Scanner class..so whenever you use nextInt you must have to create object of Scanner class then use can use nextInt. In your class main there is no any object of Scanner class so you cannt use nextInt method.
so you have to modify your code something like this

class main
{

public static void main(String args[])
{
calculator ob=new calculator();
Scanner ob1 = new Scanner(); //create Scanner class object. Now ob1 can use to call nextInt method of Scanner class.
int ch;
do
{

System.out.println("Press 1:ADDITION");
System.out.println("Press 2:SUBTRACTION");
System.out.println("Press 3:MULTIPLICATION");
System.out.println("Press 4IVISION");

System.out.println("ENTER THE CHOICE:");
ch=ob1.nextInt();
if(ch==1)
{
ob.input();
ob.sum();
ob.display();
}
...... rest of code...

are u using jdk version below 1.4 which does not support scanner class
use bufferedReader instead of that