simple java question?

Schizo265 · 07-15-2003, 02:59 AM

how do i handle input on an integer?

in this book my friend lent me, i read that i could use this and it would work.

import java.io.*;

public class RectDrawer
{
static BufferedReader keyboard = new BufferedReader(new InputStreamReader(System.in));
static PrintWriter screen = new PrintWriter(System.out,true);

public static void main(String[] args)
{
int i,j,rows,cols;

screen.println("Enter the dimension of the rectangle.");
screen.print("columns?"); screen.flush();
*cols = new Integer(keyboard.readLine()).intValue();
screen.print("rows?"); screen.flush();
*rows = new Integer(keyboard.readLine()).intValue();

screen.println("This will have three rows and three columns\n");
for (i=0;i<cols;i++) screen.print(" "+"_"); screen.println(" ");
for (j=0;j<rows;j++)
{
for (i=0;i<cols;i++) screen.print("|"+"_"); screen.println("|");
}

}
}

i put * on the lines im having trouble with. i get errors here:

Error: cannot resolve symbol
symbol : method intValue ()
location: class java.lang.String

and this one:

Error: unreported exception java.io.IOException; must be caught or declared to be thrown

argh. programming n00b. help me out.

Bill_Tür · 07-15-2003, 04:11 AM

public static void main(String[] args) throws IOException

Try this and it you get no compiler errors. There are checked and unchecked Exception. Checked Ecxeptions must be caught or thrown. Everything that deals with I/O is a checked Exception. The compiler reports an error if you didn't catch or throw an checked Exception.

Bill_Tür · 07-15-2003, 04:20 AM

Oh I forgot your first error message.

cols = (new Integer(keyboard.readLine())).intValue();

Should work. Better is the following solution. You need no Integer Object. Just use a static Method.

cols = Integer.parseInt(keyboard.readLine());