import java awt import java awt event import

import java. awt. *; import java. awt. event. *; import javax. swing. *; public class Mini. Calc extends JFrame implements Action. Listener { private JLabel left. Label, right. Label, result. Label; private JText. Field left. Operand, right. Operand, result; private JButton add. Button, sub. Button; private double left, right; public Mini. Calc () { super ("Калкулатор"); set. Default. Close. Operation(JFrame. EXIT_ON_CLOSE); Container container = get. Content. Pane(); container. set. Layout(new Grid. Layout (4, 2)); left. Label = new JLabel ("Ляв операнд"); left. Operand = new JText. Field(20); right. Label = new JLabel ("Десен операнд"); right. Operand = new JText. Field(20); result. Label = new JLabel ("Резултат"); result = new JText. Field(20); add. Button = new JButton ("+"); sub. Button = new JButton ("-");

container. add (left. Label); container. add (left. Operand); container. add (right. Label); container. add (right. Operand); container. add (result. Label); container. add (result); container. add (add. Button); container. add (sub. Button); add. Button. add. Action. Listener (this); sub. Button. add. Action. Listener(this); set. Size (300, 150); set. Visible(true); } public void action. Performed (Action. Event event) { try { left = Double. parse. Double(left. Operand. get. Text()); } catch (Exception el) { result. set. Text("Ляв операнд!!!"); return; }

try { right = Double. parse. Double(right. Operand. get. Text()); } catch (Exception er) { result. set. Text("Десен операнд!!!"); return; } if (add. Button == event. get. Source()) result. set. Text("" + (left + right)); else if (sub. Button == event. get. Source()) result. set. Text("" + (left - right)); } public static void main(String[] args) { Swing. Utilities. invoke. Later(new Runnable() { public void run() { new Mini. Calc(); } }