Adding two numbers using Applet on Mac always gives sum as 0

Question

import java.awt.*;
import java.applet.*;

public class userin extends Applet
{
TextField text1, text2;
public void init( )
{
    text1 = new TextField(8);
    text2 = new TextField(8);
    add (text1);
    add (text2);
    text1.setText ("0");
    text2.setText ("0");
}
public void paint (Graphics g)
{
    int x = 0, y = 0, z = 0;
    String s1, s2, s;
    g.drawString("input a number in each box", 10, 50);
    try
    {
        s1 = text1.getText( );
        x = Integer.parseInt(s1);
        s2 = text2.getText( );
        y = Integer.parseInt(s2);
    }
    catch (Exception ex) { }
    z = x + y;
    s = String.valueOf (z);
    g.drawString ("THE SUM IS:", 10, 75);
    g.drawString (s, 100, 75);
}
public boolean action (Event event, Object object)
{
    repaint ( );
    return true;
}

}

The following code works well on windows and gives the sum of 2 numbers, but when i use it on mac in Netbeans or Eclipse, the code runs but sum is always 0. I don't know what is causing this issue, It would be kind if someone could help out.

Answer 1

The only reason that can cause this is exception thrown in your try block that you catch an ignore:

try {
   .......
} catch (Exception e) {}

It is extremely bad practice to write empty catch block because you are actually hiding problems from yourself.

First, just remove your try/catch at all or print exception:

try {
      ...........
} catch (Exception e) {
     e.printStackTrace();
}

Now you will see your problem. I guess it is NumberFormatException thrown from Integer.parseInt() and it is caused by wrong User's input.

I believe it is not a problem of different behavior on different platform but different input that you typed on each one of the tests.