I have a problem with my calculator :(

Question

hi all,
i need some help with my calculator..after i wrote the code i discovered my mistake so i made some changes on the code..the problem is that it's still applying the old code !!
( i didn't forgot to compile it, & i closed all the browsers b4 trying it )
i will appreciate ANY suggestion
P.S : my mistake was with the operations buttons ( add, sub, multip, division ) & the equal button
if it may help, this is the code ( the new one, then the old one )
the new code:
import java.awt.* ; // Container, FlowLayout
import java.awt.event.* ; // ActionEvent, ActionListener
import javax.swing.* ; // JApplet , JButton , JLabal, JTextField
public class Calculator2 extends JApplet implements ActionListener {
// graphical user interface components
JTextField field ;
JButton zero, one, two, three, four, five, six, seven, eight, nine, fraction, clear,
add, sub, multip , division, equal ,sin , cos, tan ,log ,sqrt ,exp ;
// variables
String string = " " ; // to store what is in the text field
String operation ; // to store the operation selected
double operate ; // to store the result of the operation selected
double operand1 , operand2 ; // the operands of the operation
// set up GUI components
public void init ()
Container container = getContentPane ();
container.setLayout ( new FlowLayout () );
// create a text field
field = new JTextField ( 17 );
container.add ( field ) ;
// create buttons
clear = new JButton ( "C" ) ;
clear.addActionListener ( this ) ;
container.add ( clear );
zero = new JButton ( "0" ) ;
zero.addActionListener ( this ) ;
container.add ( zero );
one = new JButton ( "1" ) ;
one.addActionListener ( this ) ;
container.add ( one );
two = new JButton ( "2" ) ;
two.addActionListener ( this ) ;
container.add ( two );
three = new JButton ( "3" ) ;
three.addActionListener ( this ) ;
container.add ( three );
four = new JButton ( "4" ) ;
four.addActionListener ( this ) ;
container.add ( four );
five = new JButton ( "5" ) ;
five.addActionListener ( this ) ;
container.add ( five );
six = new JButton ( "6" ) ;
six.addActionListener ( this ) ;
container.add ( six );
seven = new JButton ( "7" ) ;
seven.addActionListener ( this ) ;
container.add ( seven );
eight = new JButton ( "8" ) ;
eight.addActionListener ( this ) ;
container.add ( eight );
nine = new JButton ( "9" ) ;
nine.addActionListener ( this ) ;
container.add ( nine );
fraction = new JButton ( "." ) ;
fraction.addActionListener ( this ) ;
container.add ( fraction );
add = new JButton ( "+" ) ;
add.addActionListener ( this ) ;
container.add ( add );
sub = new JButton ( "-" ) ;
sub.addActionListener ( this ) ;
container.add ( sub );
multip = new JButton ( "*" ) ;
multip.addActionListener ( this ) ;
container.add ( multip );
division = new JButton ( "�" ) ;
division.addActionListener ( this ) ;
container.add ( division );
sin = new JButton ( "sin" ) ;
sin.addActionListener ( this ) ;
container.add ( sin );
cos = new JButton ( "cos" ) ;
cos.addActionListener ( this ) ;
container.add ( cos );
tan = new JButton ( "tan" ) ;
tan.addActionListener ( this ) ;
container.add ( tan );
log = new JButton ( "log" ) ;
log.addActionListener ( this ) ;
container.add ( log );
sqrt = new JButton ( "sqrt" ) ;
sqrt.addActionListener ( this ) ;
container.add ( sqrt );
exp = new JButton ( "exp" ) ;
exp.addActionListener ( this ) ;
container.add ( exp );
equal = new JButton ( "=" ) ;
equal.addActionListener ( this ) ;
container.add ( equal );
} // end of method init
public void actionPerformed ( ActionEvent event )
     // button zero
     if ( event.getSource()== zero )
     string = string + "0" ;
     field.setText ( string ) ;
     // button one
     else if ( event.getSource()== one )
          string = string + "1" ;
          field.setText ( string ) ;
     // button two
     else if ( event.getSource()== two )
          string = string + "2" ;
          field.setText ( string ) ;
     // button three
     else if ( event.getSource()== three )
          string = string + "3" ;
          field.setText ( string ) ;
     // button four
     else if ( event.getSource()== four )
          string = string + "4" ;
          field.setText ( string ) ;
     // button five
     else if ( event.getSource()== five )
          string = string + "5" ;
          field.setText ( string ) ;
     // button six
     else if ( event.getSource()== six )
          string = string + "6" ;
          field.setText ( string ) ;
     // button seven
     else if ( event.getSource()== seven )
          string = string + "7" ;
          field.setText ( string ) ;
     // button eight
     else if ( event.getSource()== eight )
          string = string + "8" ;
          field.setText ( string ) ;
     // button nine
     else if ( event.getSource()== nine )
          string = string + "9" ;
          field.setText ( string ) ;
     // button fraction
     else if ( event.getSource()== fraction )
          string = string + "." ;
          field.setText ( string ) ;
     // button clear
     else if ( event.getSource()== clear )
          clear ();
     // button add
     else if ( event.getSource()== add )
          operand1 = Double.parseDouble ( string );
          operation = "+" ;
          clear ();
     // button sub
     else if ( event.getSource()== sub )
          operand1 = Double.parseDouble ( string );
          operation = "-" ;
          clear ();
     // button multip
     else if ( event.getSource()== multip )
          operand1 = Double.parseDouble ( string );
          operation = "*" ;
          clear ();
     // button division
     else if ( event.getSource()== division )
          operand1 = Double.parseDouble ( string );
          operation = "/" ;
          clear ();
     // button sin
     else if ( event.getSource()== sin )
          operate = Double.parseDouble ( string ) ;
          operate = Math.sin( operate );
          field.setText ( Double.toString ( operate ) ) ;
// button cos
     else if ( event.getSource()== cos )
          operate = Double.parseDouble ( string ) ;
          operate = Math.cos( operate );
          field.setText ( Double.toString ( operate ) ) ;
     // button tan
     else if ( event.getSource()== tan )
          operate = Double.parseDouble ( string ) ;
          operate = Math.tan( operate );
          field.setText ( Double.toString ( operate ) ) ;
     // button log
     else if ( event.getSource()== log )
          operate = Double.parseDouble ( string ) ;
          operate = Math.log( operate );
          field.setText ( Double.toString ( operate ) ) ;
     // button sqrt
     else if ( event.getSource()== sqrt )
          operate = Double.parseDouble ( string ) ;
          operate = Math.sqrt( operate );
          field.setText ( Double.toString ( operate ) ) ;
     // button exp
     else if ( event.getSource()== exp )
          operate = Double.parseDouble ( string ) ;
          operate = Math.exp( operate );
          field.setText ( Double.toString ( operate ) ) ;
     // button equal
     else // if ( event.getSource()== equal )
          operand2 = Double.parseDouble ( string );
          if ( operation == "+" )
               operate = operand1 + operand2 ;
          else if ( operation == "-" )
               operate = operand1 - operand2 ;
          else if ( operation == "*" )
               operate = operand1 * operand2 ;
          else if ( operation == "/" )
               operate = operand1 / operand2 ;
          field.setText ( Double.toString ( operate ) ) ;
} // end of method actionPerformed
public void clear ()
     string = " ";
     field.setText ( string ) ;
} // end of method clear
} // end of class
the old code which have the problem ( which i make the changes on ) :
     // button clear
     else if ( event.getSource()== clear )
          string = "";
          field.setText ( string ) ;
     // button add
     else if ( event.getSource()== add )
          string = string + "+" ;
          field.setText ( string ) ;
     // button sub
     else if ( event.getSource()== sub )
          string = string + "-" ;
          field.setText ( string ) ;
     // button multip
     else if ( event.getSource()== multip )
          string = string + "*" ;
          field.setText ( string ) ;
     // button division
     else if ( event.getSource()== division )
          string = string + "/" ;
          field.setText ( string ) ;
     // button equal
     else // if ( event.getSource()== equal )
          operate = Double.parseDouble ( string ) ;
          field.setText ( Double.toString ( operate ) ) ;
thanks a lot :)

Answer 1

Open Java console and press "x" (Clear cache)
Disable caching in java paremeters.