File.delete() and File.deleteOnExit() doesn't work consistently..

Question

I am seeing some odd behavior with trying to delete files that were opened. Usually just doing new File("file.txt").delete() would work. However, in this case, I have created an input stream to the file, read it in, saved it to another location (copied it), and now I am trying to delete it.
The odd thing is, in my simple application, the user can work with one file at a time, but I move "processed" files to a lower pane in a swing app. When they exit it, it then archives all the files in that lower pane. Usually every file but the last one opened deletes. However, I have seen odd behavior where by some files don't delete, sometimes all of them wont delete. I tried the deleteOnExit() call which to me should be done by the JVM after it has released all objects such that they don't matter and the JVM ignores any object refs and directly makes a call (through JNI perhaps) to the underlying OS to delete the file. This doesn't work either.
I am at a loss as to why sometimes some files delete, and other times they don't. In my processing code, I always close the input stream and set its variable to null. So I am not sure how it is possible a reference could still be held to the object representing the file on disk.

Answer 1

and then, in the other class
  public int cdplayerINIToMMCD(File aDatabase, String thePassword) throws IllegalArgumentException {
     /*---------DATA---------*/
     String dbLogin, dbPassword;
     JFileChooser fc;
     INIFileFilter ff;
     int dialogReturnVal;
     String nameChosen;
     File INIFile;
     ProgressMonitor progressMonitor;
     BufferedReader inFileStream;
     String oneLine;
     int totalLines = 0;
     int linesParsed = 0;
     boolean openDBResult;
     int hasPassword;
     if ((aDatabase == null) || (!aDatabase.exists()) ||
        (FileManagement.verifyMMCD(aDatabase) == FileManagement.VERIFY_FAILED)) {
        throw new IllegalArgumentException();       
     else { 
        currentDB = aDatabase;
        if(thePassword == null) {
          dbPassword = "";
        else { dbPassword = thePassword; }
        dbLogin = dbPassword; //For MSAccess dbLogin == dbPassword
     //Ask the user for the cdplayer.ini file.
     //Create a file chooser
     if (System.getProperty("os.name").indexOf("Windows") > -1) {
        fc = new JFileChooser("C:\\Windows");
     else {
        fc = new JFileChooser();     
     fc.setMultiSelectionEnabled(false);
     fc.setDragEnabled(false);
     //Create a new FileFilter
     ff = new INIFileFilter();
     //Add this filter to our File chooser.
     fc.addChoosableFileFilter(ff);
     fc.setFileFilter(ff);
     //Ask the user to locate it.
     do {
        dialogReturnVal = fc.showOpenDialog(mainFrame);
        if (dialogReturnVal == JFileChooser.APPROVE_OPTION) {
           nameChosen = fc.getSelectedFile().getAbsolutePath();
           if(nameChosen.toLowerCase().endsWith(INIFileFilter.FILE_TYPE)) { INIFile=new File(nameChosen); }
           else { INIFile = new File(nameChosen+INIFileFilter.FILE_TYPE); }
           if (!INIFile.exists()) {
              continue; //If the name specified does not exist, ask again.
           else { break; }
        else { //User clicked cancel in the open dialog.
           //Ignore what we've done so far.
           return(IMPORT_ABORTED);
     } while(true); //Keep asking until cancelled or a valid file is specified.
     //Determine how many lines will be parsed.
     try {
       //Open the INI for counting
       inFileStream = new BufferedReader(new InputStreamReader(new FileInputStream(INIFile)));
       while ((inFileStream.readLine()) != null) {
           totalLines++;
       //Close the INI file.
       inFileStream.close();
     } catch (IOException ex) { return(IMPORT_FAILED); }
     //Make a progress monitor that will show progress while importing.
     progressMonitor = new ProgressMonitor(mainFrame, "Importing file","", 0, totalLines);
     progressMonitor.setProgress(0);
     progressMonitor.setMillisToPopup(100);
     progressMonitor.setMillisToDecideToPopup(1);
     //Make our DatabaseHandler to insert results to the database.
     dbh = new DatabaseHandler();
     //Open the database connection.
     do {
       try {
          openDBResult = dbh.openDBConnection(currentDB, dbLogin, dbPassword);
       } catch(JDBCException ex) { return(IMPORT_JDBC_ERROR); } //OUCH! can't write anything.
         catch(SQLException ex) {
             openDBResult = DatabaseHandler.OPNCN_FAILED;
             //Can not open the database. Is it password protected?
             hasPassword = JOptionPane.showConfirmDialog(mainFrame, "Could not open the database. "+
                                            "The password is wrong or you have not specified it.\n"+
                       "Do you want to enter one now?", "New password?", JOptionPane.YES_NO_OPTION);
            if (hasPassword == MMCDCatalog.DLG_OPTN_YES) {
               dbPassword = JOptionPane.showInputDialog(mainFrame, "Please enter your "+
                                                          "password for the DataBase:");
                dbLogin = dbPassword; //For MSAccess, login == password                                                    
            //If the password wasn't the problem, then we can't help it.
            else { return(IMPORT_FAILED); }
     } while(openDBResult != DatabaseHandler.OPNCN_OK); //If it is OK, no exception thrown.
     //Import the ini file
     try {
        //Open the INI file for parsing.
        inFileStream = new BufferedReader(new InputStreamReader(new FileInputStream(INIFile)));
        //Read and parse the INI file. Save entries once parsed.
        while ((oneLine = inFileStream.readLine()) != null) {
           parseLine(oneLine);
           linesParsed++;
           progressMonitor.setNote("Entries imported so far: "+entriesImported);
           progressMonitor.setProgress(linesParsed);
           if ((progressMonitor.isCanceled()) || (linesParsed == progressMonitor.getMaximum())) {
              progressMonitor.close();
              break;
        //Close the INI file.
        inFileStream.close();
     } catch (IOException ex) {
          //Make absolutely sure the progressMonitor has disappeared
            progressMonitor.close();
            if (dbh.closeDBConnection() != DatabaseHandler.CLSCN_OK) {
             JOptionPane.showMessageDialog(mainFrame, "Error while reading the INI file.\n"+
                "Error while attempting to close the database", "Error", JOptionPane.INFORMATION_MESSAGE);
          else {
             JOptionPane.showMessageDialog(mainFrame, "Error while reading the INI file.",
                                                "Error", JOptionPane.INFORMATION_MESSAGE);     
            return(IMPORT_FAILED);
     //Make absolutely sure the progressMonitor has disappeared
     progressMonitor.close();
     //Close the database connection
     if (dbh.closeDBConnection() != DatabaseHandler.CLSCN_OK) {
        JOptionPane.showMessageDialog(mainFrame, "Error while closing the database after import.",
                                      "Error", JOptionPane.INFORMATION_MESSAGE);
     //Did the user cancel?
     if (totalLines != linesParsed) {
        return(IMPORT_ABORTED);     
     //Success!
     //Everything ok. Return the number of entries imported.
     return(entriesImported);
  }