Thêm tính năng đọc file

[hoangbuituananh132109]

import javax.swing.; import java.awt.; import java.awt.event.; import java.io.;

public class SimpleNotepad extends JFrame implements ActionListener { private JTextArea textArea; private JFileChooser fileChooser; private String currentFile;

public SimpleNotepad() {
    setTitle("Simple Notepad");
    setSize(800, 600);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    textArea = new JTextArea();
    JScrollPane scrollPane = new JScrollPane(textArea);
    add(scrollPane, BorderLayout.CENTER);

    JMenuBar menuBar = new JMenuBar();
    JMenu fileMenu = new JMenu("File");
    JMenuItem newMenuItem = new JMenuItem("New");
    newMenuItem.addActionListener(this);
    JMenuItem openMenuItem = new JMenuItem("Open");
    openMenuItem.addActionListener(this);
    JMenuItem saveMenuItem = new JMenuItem("Save");
    saveMenuItem.addActionListener(this);

    fileMenu.add(newMenuItem);
    fileMenu.add(openMenuItem);
    fileMenu.add(saveMenuItem);
    menuBar.add(fileMenu);
    setJMenuBar(menuBar);

    fileChooser = new JFileChooser();

    setVisible(true);
}

public void actionPerformed(ActionEvent e) {
    String command = e.getActionCommand();
    if (command.equals("New")) {
        textArea.setText("");
        currentFile = null;
    } else if (command.equals("Open")) {
        openFile();
    } else if (command.equals("Save")) {
        saveFile();
    }
}

private void openFile() {
    int returnVal = fileChooser.showOpenDialog(this);
    if (returnVal == JFileChooser.APPROVE_OPTION) {
        File file = fileChooser.getSelectedFile();
        try {
            FileReader reader = new FileReader(file);
            textArea.read(reader, null);
            reader.close();
            currentFile = file.getAbsolutePath();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
}

private void saveFile() {
    if (currentFile != null) {
        try {
            FileWriter writer = new FileWriter(currentFile);
            textArea.write(writer);
            writer.close();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    } else {
        int returnVal = fileChooser.showSaveDialog(this);
        if (returnVal == JFileChooser.APPROVE_OPTION) {
            File file = fileChooser.getSelectedFile();
            try {
                FileWriter writer = new FileWriter(file);
                textArea.write(writer);
                writer.close();
                currentFile = file.getAbsolutePath();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
    }
}

public static void main(String[] args) {
    SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            new SimpleNotepad();
        }
    });
}

}