package fileio;

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.*;
import javax.swing.*;
import javax.swing.filechooser.FileNameExtensionFilter;

public class Notepad extends JFrame
{
    JTextArea text = new JTextArea();
    
    JMenuItem fileOpen = new JMenuItem("Open");
    
    class Opener implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
            JFileChooser chooser = new JFileChooser();
            FileNameExtensionFilter filter = 
                new FileNameExtensionFilter("Text and Source code", "txt", "java");
            chooser.setFileFilter(filter);
            int returnVal = chooser.showOpenDialog(null);
            if(returnVal == JFileChooser.APPROVE_OPTION) 
            {
                File file = chooser.getSelectedFile();
                read(file);
            }
        }
    }
    
    public Notepad()
    {
        super("Notepad");
    
        getContentPane().setLayout(new BorderLayout());
        getContentPane().add(new JScrollPane(text));
        
        JMenu file = new JMenu("File");
        file.add(fileOpen);
        
        JMenuBar bar = new JMenuBar();
        bar.add(file);
        
        setJMenuBar(bar);
        
        fileOpen.addActionListener(new Opener());
        
        setSize(500,400);
        setVisible(true);
    }
    
    private void read(File name)
    {
        try
        {
            FileReader fr = new FileReader(name);
            BufferedReader in = new BufferedReader(fr);
        
            String line = in.readLine();
            while (line != null)
            {
                text.append(line + "\n");
                line = in.readLine();
            }
            
            in.close();
            fr.close();
        }
        catch(IOException e)
        {
            JOptionPane.showMessageDialog(this, "ERROR: " + e);
        }
    }
    
    public static void main(String args[])
    {
        Notepad n = new Notepad();
    }
}