import javax.swing.*; import java.awt.*; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.script.ScriptEngineManager; import javax.script.ScriptEngine; import javax.script.ScriptException; public class Calculator extends JFrame implements ActionListener { private JTextField display; private StringBuilder input; public Calculator() { input = new StringBuilder(); display = new JTextField(); display.setEditable(false); display.setFont(new Font("Arial", Font.BOLD, 32)); display.setHorizontalAlignment(JTextField.RIGHT); display.setBackground(Color.LIGHT_GRAY); JPanel panel = new JPanel(); panel.setLayout(new GridLayout(4, 4, 10, 10)); panel.setBackground(Color.GRAY); String[] buttons = { "7", "8", "9", "/", "4", "5", "6", "*", "1", "2", "3", "-", "C", "0", "=", "+" }; for (String text : buttons) { JButton button = new JButton(text); button.setFont(new Font("Arial", Font.PLAIN, 24)); button.addActionListener(this); button.setBackground(Color.WHITE); panel.add(button); } add(display, BorderLayout.NORTH); add(panel, BorderLayout.CENTER); setTitle("Calculator"); setSize(400, 500); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setLocationRelativeTo(null); } @Override public void actionPerformed(ActionEvent e) { String command = e.getActionCommand(); if (command.charAt(0) == 'C') { input.setLength(0); display.setText(""); } else if (command.charAt(0) == '=') { try { double result = evaluate(input.toString()); display.setText(String.valueOf(result)); input.setLength(0); } catch (ScriptException ex) { display.setText("Error"); input.setLength(0); } } else { input.append(command); display.setText(input.toString()); } } private double evaluate(String expression) throws ScriptException { ScriptEngine engine = new ScriptEngineManager().getEngineByName("JavaScript"); return ((Number) engine.eval(expression)).doubleValue(); } //11122222 public static void main(String[] args) { SwingUtilities.invokeLater(() -> { Calculator calculator = new Calculator(); calculator.setVisible(true); }); } }