Java Notes: Example - Read into textarea

// FileIoDemo/FileInput.java -- Demonstrate File Input
// Fred Swartz - December 2004

package FileIoDemo;

import javax.swing.*;

public class FileInput { 
    public static void main(String[] args) {
        JFrame window = new FileInputGUI();
        window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        window.setVisible(true);
    }
}

// FileIoDemo/FileInputGUI.java -- Demonstrate File Input
// Fred Swartz - December 2004

package FileIoDemo;

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

class FileInputGUI extends JFrame {
    JTextArea    m_fileContents = new JTextArea(20, 80);
    JFileChooser m_fc = new JFileChooser(".");
    
    //======================================================= constructor
    FileInputGUI() {
        //... Create a button to open a file.
        JButton openFileBtn = new JButton("Open");
        openFileBtn.addActionListener(new OpenAction());
        
        //... Create a "controls" panel with button on it.
        JPanel controls = new JPanel();
        controls.setLayout(new FlowLayout());
        controls.add(openFileBtn);
        
        //... Create the content pane with controls and a textarea.
        JPanel content = new JPanel();
        content.setLayout(new BorderLayout());
        content.add(controls, BorderLayout.NORTH);
        content.add(new JScrollPane(m_fileContents), BorderLayout.CENTER);
        
        this.setContentPane(content);
        this.pack();
        this.setTitle("File Input");
    }
    
    ////////////////////////////////////// inner listener class OpenAction
    class OpenAction implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            int retval = m_fc.showOpenDialog(FileInputGUI.this);
            if (retval == JFileChooser.APPROVE_OPTION) {
                File inFile = m_fc.getSelectedFile();
                try {
                    FileReader fr = new FileReader(inFile);
                    BufferedReader bufRdr = new BufferedReader(fr);
                    
                    String line = null;
                    while ((line = bufRdr.readLine()) != null){
                        m_fileContents.append(line);
                        m_fileContents.append("\n");
                    }
                    bufRdr.close();
                    
                } catch (IOException ioex) {
                    System.err.println(ioex);
                    System.exit(1);
                }
            }
        }//end actionPerformed
    }//end inner listener class OpenAction
}