ADD file via upload

SimpleCalculator.java

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+package Calculate;
+
+import javax.script.ScriptEngine;
+import javax.script.ScriptEngineManager;
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+
+public class SimpleCalculator extends JFrame {
+    private JTextField inputField; // 输入显示区域
+
+    public SimpleCalculator() {
+        createUI();
+    }
+
+    private void createUI() {
+        // 设置窗口布局
+        setLayout(new BorderLayout());
+
+        // 创建输入显示区域
+        inputField = new JTextField("0");
+        inputField.setEditable(false);
+        inputField.setHorizontalAlignment(JTextField.RIGHT);
+        add(inputField, BorderLayout.NORTH);
+
+        // 创建面板用于放置按钮
+        JPanel panel = new JPanel();
+        panel.setLayout(new GridLayout(5, 4, 5, 5)); // 设置间距
+
+        // 创建数字和运算符按钮
+        String[] buttons = {"7", "8", "9", "/", "4", "5", "6", "*", "1", "2", "3", "-", "0", ".", "=", "+", "C", "Backspace"};
+        for (String b : buttons) {
+            JButton button = new JButton(b);
+            panel.add(button);
+            button.addActionListener(e -> press(e.getActionCommand()));
+        }
+
+        // 添加面板到窗口
+        add(panel, BorderLayout.CENTER);
+
+        // 设置窗口属性
+        setSize(300, 400); // 设置窗口大小
+        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+        setTitle("Simple Calculator");
+        setVisible(true);
+    }
+
+    private void press(String command) {
+        if ("C".equals(command)) {
+            clear();
+        } else if ("Backspace".equals(command)) {
+            backspace();
+        } else if ("=".equals(command)) {
+            calculate();
+        } else {
+            if (inputField.getText().equals("0") && !command.equals(".")) {
+                inputField.setText(command);
+            } else {
+                inputField.setText(inputField.getText() + command);
+            }
+        }
+    }
+
+    private void clear() {
+        inputField.setText("0");
+    }
+
+    private void backspace() {
+        String currentText = inputField.getText();
+        if (!currentText.isEmpty()) {
+            inputField.setText(currentText.substring(0, currentText.length() - 1));
+        }
+    }
+
+    private void calculate() {
+        String expression = inputField.getText();
+        try {
+            ScriptEngine engine = new ScriptEngineManager().getEngineByName("JavaScript");
+            Object result = engine.eval(expression);
+            inputField.setText(result.toString());
+        } catch (Exception e) {
+            JOptionPane.showMessageDialog(this, "Invalid input", "Error", JOptionPane.ERROR_MESSAGE);
+        }
+    }
+
+    public static void main(String[] args) {
+        SwingUtilities.invokeLater(SimpleCalculator::new);
+    }
+}