Unable to 'read' text file after creating and adding data to it

Question

I've received help regarding how to append the text file, but now it seems I've broken something else. I'm not able to 'read' the file.

What I'm trying to do is:

1. Enter data from the GUI text fields
2. Click the save button(creating the file and appending data to the .txt file)
3. Be able to READ from the file back to the panel

I'm doing something dumb again, I fear.

Below is my java code for the GUI, the CreateTextFile, and the ReadTextFile

import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.SQLException;

import javax.swing.*;

public class DonorGUI extends JFrame
{

    // Components
    private JPanel panel;
    private JTextArea results;
    private JButton entryButton;
    private JButton exitButton;
    private JButton clearButton;
    private JButton saveButton;
    private JButton openButton;
    private JTextField donorField;
    private JTextField charityField;
    private JTextField pledgeField;

    //create variables
    String[] donorName = new String[20];
    String[] charityName = new String[20];
    double[] donationAmt = new double[20];
    int i = 0;


    // Constants for the window size
    private final int WINDOW_WIDTH = 750;
    private final int WINDOW_HEIGHT = 525;

    //Constructor
    public DonorGUI(){

        // Set the title.
        setTitle("Wounded Warrior Donation Tracker.");

        // Specify what happens when the close button is clicked.
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        // Build the panel that contains the other components.
        buildPanel();

        // Add the panel to the content pane.
        add(panel);

        // Size and display the window.
        setSize(WINDOW_WIDTH, WINDOW_HEIGHT);
        setVisible(true);
    }

    //The buildPanel method creates a panel containing other components.
    private void buildPanel(){

        // Create labels to display instructions.
        JLabel message1 = new JLabel("Name of the Donor:");
        JLabel message2 = new JLabel("Name of the Charity:");
        JLabel message3 = new JLabel("Amount of the Pledge:");

        //instantiate the results area
        results = new JTextArea(25,60);
        results.setEditable(false);
        results.setWrapStyleWord(true);
        results.setLineWrap(true);
        results.setBorder(BorderFactory.createLoweredBevelBorder());


        // Create text fields to receive user input
        donorField = new JTextField(10);
        charityField = new JTextField(10);
        pledgeField = new JTextField(10);


        //create the user buttons to cause action
        entryButton = new JButton("Enter Donation.");
        entryButton.addActionListener(new EntryButtonListener());
        exitButton = new JButton("EXIT");
        exitButton.addActionListener(new ExitButtonListener());
        clearButton = new JButton ("Clear Fields");
        clearButton.addActionListener(new ClearButtonListener());
        saveButton = new JButton ("Save");
        saveButton.addActionListener(new SaveButtonListener());
        openButton = new JButton ("Open");
        openButton.addActionListener(new OpenButtonListener());

        // Create a panel.
        panel = new JPanel();
        panel.setBackground(Color.orange);

        //set the LayoutManager
        panel.setLayout(new FlowLayout());

        // Add the labels, text fields, and button to the panel.
        panel.add(message1);
        panel.add(donorField);
        panel.add(message2);
        panel.add(charityField);
        panel.add(message3);
        panel.add(pledgeField);
        panel.add(results);
        panel.add(entryButton);
        panel.add(clearButton);
        panel.add(saveButton);
        panel.add(openButton);
        panel.add(exitButton);      
    }
    private class EntryButtonListener implements ActionListener {

        public void actionPerformed(ActionEvent e) {

            donorName[i] = donorField.getText();
            charityName[i] = charityField.getText();
            if (donationAmt(pledgeField.getText())) {
                  donationAmt[i] = Double.parseDouble(pledgeField.getText());
            }else{
                donorField.setText("");
                charityField.setText("");
                pledgeField.setText("");
            }
            results.append(donorName[i]+" "+charityName[i]+" "+donationAmt[i]+"\n ");
            donorField.setText("");
            charityField.setText("");
            pledgeField.setText("");
            i++;
        } 
    }
    public boolean donationAmt(String amount) {

        if(amount==null || amount=="" || amount.length()<1){  //checking for empty field
            JOptionPane.showMessageDialog(null, "Please enter amount pledged");
            return false;
        }
        for(int i = 0; i < amount.length(); i++){  //verifying dollar amount entered as number
                if (!Character.isDigit(amount.charAt(i)) && amount.charAt(i)!='.'){ 
                    JOptionPane.showMessageDialog(null, "Invalid input.");
                    return false;
                } 
        }
        return true;

    }  
    private class ClearButtonListener implements ActionListener {

        public void actionPerformed (ActionEvent e) {
            donorField.setText("");
            charityField.setText("");
            pledgeField.setText("");
            }
    }
    private class ExitButtonListener implements ActionListener {

        public void actionPerformed(ActionEvent e) {
            System.exit(0);
        }
    }
    private class SaveButtonListener implements ActionListener {

        public void actionPerformed(ActionEvent e) {

            CreateTextFile cr = new CreateTextFile();
            cr.openFile();
            cr.addRecords(donorName, charityName, donationAmt);
            cr.closeFile();

            JavaDBClass db = new JavaDBClass();



        }

    }
    private class OpenButtonListener implements ActionListener {

        public void actionPerformed(ActionEvent e) {

            ReadTextFile read = new ReadTextFile();
            read.openFile();
            DonorGUI donor = read.readRecords();
            read.closeFile();           
            JavaDBClass db = new JavaDBClass(donor);
            for(int i = 0;i<donor.donationAmt.length;i++){

                try {
                    results.append(db.showTable()[i]+"\n");
                } catch (SQLException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
                }

            }
        }

    }

    /* Application method */
    public static void main(String[] args){

        DonorGUI rpc = new DonorGUI();
    }
}

CREATE TEXT FILE JAVA CODE:

/** This will create a text file based on user input and save it as donations.txt.
 * 
 */
import java.io.FileNotFoundException;
import java.util.Formatter;
import java.util.FormatterClosedException;
import java.util.NoSuchElementException;

public class CreateTextFile {

    //object that outputs text to a file
    private Formatter output;

    //try opening a file
    public void openFile(){

        try
        {
            output = new Formatter(new FileOutputStream("C:/temp/donations.txt", true));
        }
        catch (SecurityException securityException)
        {
            System.out.println("You cannot write to this file.");
        }
        catch (FileNotFoundException notFoundException)
        {
            System.out.println("You couldn't open or find the file.");
        }

    }
    //try writing to the file
    public void addRecords(String[] donor, String[] charity, double[] donation){

                try{
                     for (int j=0; j<donor.length; j++) {
                         if (donor[j] != null) {
                            output.format("\n%s %s %.2f",donor[j],charity[j],donation[j]);

                           }
                     }
              }

              catch (FormatterClosedException formatterClosedException){

                     System.out.println("You couldn't write to this file.");

              }

              catch (NoSuchElementException elementException){

                     System.out.println("Invalid Input.");

              }

       }
    //try closing the file
    public void closeFile(){
        if(output!=null)
            output.close();
    }
}

READ TEXT FILE JAVA CODE:

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class ReadTextFile {

    private Scanner input;

    //try to open the file
    public void openFile(){
        try{
            input = new Scanner(new File("C:/temp/donations.txt"));
        }
        catch (FileNotFoundException fileNotFoundException)
        {
            System.out.println("File not found.");
            System.exit(1);
        }
    }
    //try to read from the file
    public DonorGUI readRecords(){

        DonorGUI gui = new DonorGUI();

        while(input.hasNext())
        {
            for(int j = 0;j<20;j++){
            gui.donorName[j] = input.next();
            gui.charityName[j] = input.next();
            gui.donationAmt[j] = input.nextDouble();
            }
        }
        return gui;

    }
    //try to close the file
    public void closeFile(){
        if(input!=null)
            input.close();

    }
}

ERRORS RECEIVED:

Exception in thread "AWT-EventQueue-0" java.util.InputMismatchException
    at java.util.Scanner.throwFor(Scanner.java:840)
    at java.util.Scanner.next(Scanner.java:1461)
    at java.util.Scanner.nextDouble(Scanner.java:2387)
    at ReadTextFile.readRecords(ReadTextFile.java:39)
    at DonorGUI$OpenButtonListener.actionPerformed(DonorGUI.java:191)
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
    at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
    at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
    at java.awt.Component.processMouseEvent(Component.java:6288)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
    at java.awt.Component.processEvent(Component.java:6053)
    at java.awt.Container.processEvent(Container.java:2041)
    at java.awt.Component.dispatchEventImpl(Component.java:4651)
    at java.awt.Container.dispatchEventImpl(Container.java:2099)
    at java.awt.Component.dispatchEvent(Component.java:4481)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4577)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4238)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168)
    at java.awt.Container.dispatchEventImpl(Container.java:2085)
    at java.awt.Window.dispatchEventImpl(Window.java:2478)
    at java.awt.Component.dispatchEvent(Component.java:4481)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:643)
    at java.awt.EventQueue.access$000(EventQueue.java:84)
    at java.awt.EventQueue$1.run(EventQueue.java:602)
    at java.awt.EventQueue$1.run(EventQueue.java:600)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
    at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98)
    at java.awt.EventQueue$2.run(EventQueue.java:616)
    at java.awt.EventQueue$2.run(EventQueue.java:614)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:613)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
BUILD SUCCESSFUL (total time: 8 seconds)

Answer 1

In the openFile() method:

input = new Scanner(new FileInputStream("C:/temp/donations.txt"));

In the readRecords() method:

try {
  int j=0;
  while (input.hasNextLine()){
    String line=input.nextline().trim();
    if (!line.equals("")){
      String inp[]=line.split("\s");
      gui.donorName[j] = inp[0];
      gui.charityName[j] = inp[1];
      gui.donationAmt[j++] = Double.parseDouble(inp[2]);
    }
    if (j==20){break;} //don't understand why you need this but see it in your code
  }
}catch (Exception e){
   e.printStackTrace();
}