Opening java files to GUI

Question

I am creating a program to open a java file to the GUI
I want to have a filechooser which will open the file to a text display of the GUI. How do i get to open the file and the display goes to the Text area (GUI).

Answer 1

import java.awt.*;
import javax.swing.*;
import java.io.*;
import java.awt.event.*;
public class Frame1
    extends JFrame {
  JPanel panel1 = new JPanel();
  BorderLayout borderLayout1 = new BorderLayout();
  JMenuBar jMenuBar1 = new JMenuBar();
  JMenu jMenu1 = new JMenu();
  JMenuItem jMenuItem1 = new JMenuItem();
  JScrollPane jScrollPane1 = new JScrollPane();
  JTextArea jTextArea1 = new JTextArea();
  JMenuItem jMenuItem2 = new JMenuItem();
  public Frame1(String title) {
    super(title);
    try {
      jbInit();
      pack();
    catch (Exception ex) {
      ex.printStackTrace();
  public Frame1() {
    this("");
  private void jbInit() throws Exception {
    panel1.setLayout(borderLayout1);
    jMenu1.setMnemonic('F');
    jMenu1.setText("File");
    jMenuItem1.setMnemonic('O');
    jMenuItem1.setText("Open");
    jMenuItem1.addActionListener(new Frame1_jMenuItem1_actionAdapter(this));
    jTextArea1.setText("jTextArea1");
    jMenuItem2.setMnemonic('E');
    jMenuItem2.setText("Exit");
    jMenuItem2.addActionListener(new Frame1_jMenuItem2_actionAdapter(this));
    getContentPane().add(panel1);
    panel1.add(jScrollPane1, BorderLayout.CENTER);
    jScrollPane1.getViewport().add(jTextArea1, null);
    jMenuBar1.add(jMenu1);
    jMenu1.add(jMenuItem1);
    jMenu1.add(jMenuItem2);
    setJMenuBar(jMenuBar1);
    setDefaultCloseOperation(JDialog.EXIT_ON_CLOSE);
  public static void main(String[] args) {
    Frame1 f = new Frame1();
    f.setLocation(50, 50);
    f.setSize(new Dimension(640, 480));
//    dlg.pack();
    f.show();
  void jMenuItem2_actionPerformed(ActionEvent e) {
    System.exit(0);
  void jMenuItem1_actionPerformed(ActionEvent e) {
    JFileChooser jfc = new JFileChooser(System.getProperty("user.home"));
    jfc.setFileFilter(
        new javax.swing.filechooser.FileFilter() {
       * Whether the given file is accepted by this filter.
      public boolean accept(File f) { return f.isDirectory() || f.getName().endsWith("java"); }
       * The description of this filter. For example: "JPG and GIF Images"
       * @see FileView#getName
      public String getDescription() { return "Java sourcer file (*.java)"; }
    jfc.showOpenDialog(this);
    File f = jfc.getSelectedFile();
    if (f != null) {
      FileInputStream fis = null;
      byte[] buf = null;
      try {
        fis = new FileInputStream(f);
        buf = new byte[fis.available()];
        fis.read(buf);
        jTextArea1.setText(new String(buf));
        jTextArea1.setCaretPosition(0);
      catch (Exception ex) {
        JOptionPane.showMessageDialog(this, ex.toString(), "Error Reading File", JOptionPane.ERROR_MESSAGE);
      finally {
        if (fis != null) {
          try {
            fis.close();
          catch (IOException ex1) {
class Frame1_jMenuItem2_actionAdapter
    implements java.awt.event.ActionListener {
  Frame1 adaptee;
  Frame1_jMenuItem2_actionAdapter(Frame1 adaptee) {
    this.adaptee = adaptee;
  public void actionPerformed(ActionEvent e) {
    adaptee.jMenuItem2_actionPerformed(e);
class Frame1_jMenuItem1_actionAdapter
    implements java.awt.event.ActionListener {
  Frame1 adaptee;
  Frame1_jMenuItem1_actionAdapter(Frame1 adaptee) {
    this.adaptee = adaptee;
  public void actionPerformed(ActionEvent e) {
    adaptee.jMenuItem1_actionPerformed(e);
}