Trying to move inner class to a class file

Question

Hi folks,
I keep getting an error which puzzles me. I cut the following class (MyDocumentListener) out of an outer class (CenterPanel).
MyDocumentListener compiles OK but...
Now when I compile the outerclass I get the folowing error:
C:\divelog> javac -classpath C:\ CenterPanel.java
CenterPanel.java:54: cannot access divelog.MyDocumentListener
bad class file: C:\divelog\MyDocumentListener.class
class file contains wrong class: MyDocumentListener
Please remove or make sure it appears in the correct subdirectory of the classpath.
MyDocumentListener myDocumentListener = new MyDocumentListener(); // define
the listener class
^
1 error
... yes I checked, it is there..
C:\divelog>dir m*.j*
Directory of C:\divelog
MYDOCU~1 JAV 936 03-04-03 11:16p MyDocumentListener.java
====================================================================
MyDocumentListener tests to see if the current document has changed.
Required fields: boolean documentWasChanged;
import javax.swing.event.*;
// ------ Document listener class -----------
public class MyDocumentListener implements DocumentListener {
public void insertUpdate(DocumentEvent e) {
wasChanged(e);
public void removeUpdate(DocumentEvent e) {
wasChanged(e);
public void changedUpdate(DocumentEvent e) {
public boolean wasChanged(DocumentEvent e) {
// indicate that the document was changed
//and test before opening another file or closing the application.
boolean documentWasChanged = true;
return documentWasChanged;
} // close class MyDocumentListener
====================================================================
package divelog;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.lang.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.filechooser.*;
// import javax.swing.text.JTextComponent.*;
import javax.swing.text.*;
public class CenterPanel extends JPanel implements ActionListener
{ // Opens class
static private final String newline = "\n";
private JTextArea comments;
private JScrollPane scrollpane;
private JButton saveButton, openButton;
private JLabel whiteshark;
private Box box;
private BufferedReader br ;
private String str;
private JTextArea instruct;
private File defaultDirectory = new File("C://divelog");
private File fileDirectory = null;
private File currentFile= null;
// public boolean changed;
public boolean documentWasChanged;
public CenterPanel()
{ // open constructor CenterPanel
setBackground(Color.white);
comments = new JTextArea("Enter comments, such as " +
"location, water conditions, sea life you observed," +
" and problems you may have encountered.", 15, 10);
comments.setLineWrap(true);
comments.setWrapStyleWord(true);
comments.setEditable(true);
comments.setFont(new Font("Times-Roman", Font.PLAIN, 14));
// add a document listener for changes to the text,
// query before opening a new file to decide if we need to save changes.
MyDocumentListener myDocumentListener = new MyDocumentListener(); // define the listener class
comments.getDocument().addDocumentListener(myDocumentListener); // create the reference for the class
scrollpane = new JScrollPane(comments);
scrollpane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
saveButton = new JButton("Save Comments", new ImageIcon("images/Save16.gif"));
saveButton.addActionListener( this );
saveButton.setToolTipText("Click this button to save the current file.");
openButton = new JButton("Open File...", new ImageIcon("images/Open16.gif"));
openButton.addActionListener( this );
openButton.setToolTipText("Click this button to open a file.");
whiteshark = new JLabel("", new ImageIcon("images/gwhite.gif"), JLabel.CENTER);
Box boxH;
boxH = Box.createHorizontalBox();
boxH.add(openButton);
boxH.add(Box.createHorizontalStrut(15));
boxH.add(saveButton);
box = Box.createVerticalBox();
box.add(scrollpane);
box.add(Box.createVerticalStrut(10));
box.add(boxH);
box.add(Box.createVerticalStrut(15));
box.add(whiteshark);
add(box);
} // closes constructor CenterPanel
public void actionPerformed( ActionEvent evt )
{ // open method actionPerformed
// --------- test to see if the current file was modified and give an option to save first.
if (documentWasChanged) // add and IF filename not null
// ----- display pop-up alert --------------------------------------------------------------
int confirm = JOptionPane.showConfirmDialog(null,
"Click OK to discard current changes, \n or Cancel to save before proceeding.", // msg
"Unsaved Modifications!", // title
JOptionPane.OK_CANCEL_OPTION, // buttons displayed
// JOptionPane.ERROR_MESSAGE
// JOptionPane.INFORMATION_MESSAGE
// JOptionPane.PLAIN_MESSAGE
// JOptionPane.QUESTION_MESSAGE
JOptionPane.WARNING_MESSAGE,
null);
if (confirm != JOptionPane.YES_OPTION) //user wants to save changes
try {
// let user save the file
catch(Exception e) {}
else // let user open a new file
} // close "if (documentWasChanged)" - display pop-up alert ----------
JFileChooser jfc = new JFileChooser();
     //Add a custom file filter and disable the default "Accept All" file filter.
jfc.addChoosableFileFilter(new JTFilter()); // /** found in Utils.java /*
jfc.setAcceptAllFileFilterUsed(false);
// -- open the default directory --
// public void setCurrentDirectory(File dir)
// jfc.setCurrentDirectory(new File("C://divelog"));
jfc.setCurrentDirectory(defaultDirectory);
jfc.setSize(400, 300);
jfc.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES);
Container parent = saveButton.getParent();
//========================= Test Button Actions ================================
//========================= Open Button ================================
if (evt.getSource() == openButton)
int choice = jfc.showOpenDialog(CenterPanel.this);
File file = jfc.getSelectedFile();
// --------- change test was here -----------
/* a: */
if (file != null && choice == JFileChooser.APPROVE_OPTION)
String filename = jfc.getSelectedFile().getAbsolutePath();
// -- get the current directory name -------
// public File getCurrentDirectory( );
File f=new File(System.getProperty("user.dir"));
fileDirectory = jfc.getCurrentDirectory();
// -- remember the last directory used --
if (defaultDirectory != fileDirectory)
{defaultDirectory = fileDirectory;}
try
{ //opens try         
comments.getLineCount( );
// -- clear the old data before importing the new file --
comments.selectAll();
comments.replaceSelection("");
// -- get the new data ---
br = new BufferedReader (new FileReader(file));
while ((str = br.readLine()) != null)
{//opens while
comments.append(str);
} //closes while
} // close try
catch (IOException ioe)
{ // open catch
comments.append(newline +"Open command not successful:" + ioe + newline);
} // close catch
// ---- display the values of the directory variables -----------------------
comments.append(
newline + "The f directory variable contains: " + f +
newline + "The fileDirectory variable contains: " + fileDirectory +
newline + "The defaultDirectory variable contains: " + defaultDirectory );
else
comments.append("Open command cancelled by user." + newline);
} //close if statement /* a: */
//========================= Save Button ================================
} else if (evt.getSource() == saveButton)
int choice = jfc.showSaveDialog(CenterPanel.this);
if (choice == JFileChooser.APPROVE_OPTION)
File fileName = jfc.getSelectedFile();
// -- get the current directory name -------
// public File getCurrentDirectory( );
File f=new File(System.getProperty("user.dir"));
fileDirectory = jfc.getCurrentDirectory();
// -- remember the last directory used --
if (defaultDirectory != fileDirectory)
{defaultDirectory = fileDirectory;}
//check for existing files. Warn users & ask if they want to overwrite
for(int i = 0; i < fileName.length(); i ++) {
File tmp = null;
tmp = (fileName);
if (tmp.exists()) // display pop-up alert
//public static int showConfirmDialog( Component parentComponent,
// Object message,
// String title,
// int optionType,
// int messageType,
// Icon icon);
int confirm = JOptionPane.showConfirmDialog(null,
fileName + " already exists on " + fileDirectory
+ "\n \nContinue?", // msg
"Warning! Overwrite File!", // title
JOptionPane.OK_CANCEL_OPTION, // buttons displayed
                    // JOptionPane.ERROR_MESSAGE
                    // JOptionPane.INFORMATION_MESSAGE
                    // JOptionPane.PLAIN_MESSAGE
                    // JOptionPane.QUESTION_MESSAGE
JOptionPane.WARNING_MESSAGE,
null);
if (confirm != JOptionPane.YES_OPTION)
{ //user cancels the file overwrite.
try {
jfc.cancelSelection();
break;
catch(Exception e) {}
// ----- Save the file if everything is OK ----------------------------
try
{ // opens try
BufferedWriter bw = new BufferedWriter(new FileWriter(fileName));
bw.write(comments.getText());
bw.flush();
bw.close();
comments.append( newline + newline + "Saving: " + fileName.getName() + "." + newline);
break;
} // closes try
catch (IOException ioe)
{ // open catch
comments.append(newline +"Save command unsuccessful:" + ioe + newline);
} // close catch
} // if exists
} //close for loop
else
comments.append(newline + "Save command cancelled by user." + newline);
// ========= }
} // end-if save button
} // close method actionPerformed
} //close constructor CenterPanel
// <<<<<<<<<<<<<<<<<
// <<<<<<<<<<<<<<<<< MyDocumentListener class was here <<<<<<<<<<<<<<<<<
// <<<<<<<<<<<<<<<<<
} // Closes class CenterPanel

Answer 1

You didn't put your MyDocumentListener class in the package divelog.
Add
package divelog;to the top of MyDocumentListener.java and recompile.