Input and Output - Java - page 377

case case StreamTokenizer . TT_NUMBER : // Found a number, push value to stack

push ( tf . nval );
break break ;

case case StreamTokenizer . TT_WORD :

// Found a variable, save its name. Not used here.
variable = tf . sval ;
break break ;

case case '+' :

// + operator is commutative.
push ( pop () + pop ());
break break ;

case case '-' :

// - operator: order matters.
tmp = pop ();
push ( pop () - tmp );
break

break ;

case case '*' :

// Multiply is commutative
push ( pop () * pop ());
break break ;

case case '/' :

// Handle division carefully: order matters!
tmp = pop ();
push ( pop () / tmp );
break

break ;

case case '=' :

out . println ( peek ());
break

break ;
default default :

out . println ( "What's this? iType = " + iType );

}

}

}
void

void push ( double double val ) {

s . push ( new new Double ( val ));

}
double

double pop () {
return return (( Double ) s . pop ()). doubleValue ();

}
double double peek () {

return

return (( Double ) s . peek ()). doubleValue ();

}
void

void clearStack () {
s . removeAllElements ();

}

}