كيفية التحويل من الريال الى الدولار

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

public class Converts extends Applet
implements ActionListener {

Label labelDollars, labelRyal;
TextField txtDollar,txtRyal;
Button btnConvert;

public void init() {
labelDollars = new Label("USD");
add(labelDollars);
txtDollar = new TextField(10);
add(txtDollar);
labelRyal = new Label("RO");
add(labelRyal);
txtRyal = new TextField(10);
add(txtRyal);
btnConvert=new Button("CONVERT");
add(btnConvert);
btnConvert.addActionListener(this);
}
public void actionPerformed(ActionEvent e) {

if(e.getSource() == btnConvert) {
float omr = Float.parseFloat(txtDollar.getText()) * 0.3581f;
txtRyal.setText(String.valueOf(omr));
}
}
}

import java.awt.*;