File Problem

Question

Could anyone help me please, it is very urgent, when i run the below code i got a nullException in main method ???
Input.txt
12.36 52.36
23.23 56.52
24.63 60.25
30.2 65.23
32.3 68.33
35.26 70.52
40 75.23
42.12 80.54
45.36 85.52
FileRecord.java
package com.bhaidar.machinery.struct;
import java.io.Serializable;
public class FileRecord implements Serializable {
private double thickness;
private double angle;
public FileRecord()
this(0.0, 0.0);
public FileRecord( double thick, double degree )
setThickness( thick );
setAngle( degree );
public void setThickness( double thick )
thickness = thick;
public double getThickness() { return thickness; }
public void setAngle( double degree )
angle = degree;
public double getAngle() { return angle; }
ReadFile.java
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import java.text.DecimalFormat;
import javax.swing.*;
import com.bhaidar.machinery.struct.FileRecord;
public class ReadFile extends JFrame {
private ObjectInputStream input1;
private JButton readb;
private JTextArea output;
private JScrollPane scroller = new JScrollPane( output );
private String outfile = " ";
private File file1, file2;
private FileInputStream fileInput1, fileInput2;
private double arraythick[], arraydegree[];
public ReadFile () {
super("Reading from a file");
getContentPane().setLayout( new BorderLayout() );
output = new JTextArea(10,5);
readb = new JButton("Read the File");
readb.addActionListener(
new ActionListener() {
public void actionPerformed(ActionEvent e)
readIt();
getContentPane().add(readb,BorderLayout.SOUTH);
readb.setEnabled( false );
outfile += "Thickness\tAngle\n";
for(int j=0; j<arraythick.length; j++)
outfile += arraythick[j] + "\t" + arraydegree[j] + "\n";
output.setText( outfile );
getContentPane().add(scroller,BorderLayout.CENTER);
private void openFile( )
file1 = new File("input.txt");
if ( file1 == null ||
file1.getName().equals( "" ) )
JOptionPane.showMessageDialog( this,"Invalid File Name",
"Invalid File Name",JOptionPane.ERROR_MESSAGE );
else {
// Open the file
try {
// close file from previous operation
if ( input1 != null )
input1.close();
fileInput1 = new FileInputStream( file1 );
input1 = new ObjectInputStream( fileInput1 );
catch ( IOException e ) {
JOptionPane.showMessageDialog( this,
"File does not exist",
"Invalid File Name",
JOptionPane.ERROR_MESSAGE );
private void closeFile()
try {
input1.close();
catch ( IOException ioe ) {
JOptionPane.showMessageDialog( this,
"Error closing file",
"Error", JOptionPane.ERROR_MESSAGE );
System.exit( 1 );
private void readIt() {
FileRecord record;
openFile();
try {
// input the values from the file
int index = 0;
while ( true ) {
record =
( FileRecord ) input1.readObject();
arraythick[index+1] = record.getThickness();
arraydegree[index+1] = record.getAngle();
catch ( EOFException eof ) {
closeFile();
catch ( ClassNotFoundException cnfex ) {
JOptionPane.showMessageDialog( this,
"Unable to create object",
"Class Not Found", JOptionPane.ERROR_MESSAGE );
catch ( IOException e ) {
JOptionPane.showMessageDialog( this,
"Error reading from file",
"Error", JOptionPane.ERROR_MESSAGE );
public static void main( String args[] )
final ReadFile app = new ReadFile();
app.setSize(300, 300);
app.addWindowListener(
new WindowAdapter() {
public void windowClosing( WindowEvent e )
app.closeFile();
System.exit( 0 );
app.show();
haidar, bilal

Answer 1

thank you for the hint you were right, but i am still getting an exception when i click the button to start reading from the text file, can you please check this for me.
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import java.text.DecimalFormat;
import javax.swing.*;
import java.util.*;
public class ReadFile extends JFrame {
     private BufferedReader bfile1;
     private JButton readb;
     private JTextArea output;
     private JScrollPane scroller = new JScrollPane( output );
     private String outfile = " ";
     private FileReader file1, file2;
     private double arraythick[], arraydegree[];
     public ReadFile () {
          super("Reading from a file");
          arraythick = new double[500];
          arraydegree = new double[500];
          this.getContentPane().setLayout( new BorderLayout() );
          output = new JTextArea(10,5);
          readb = new JButton("Read the File");
          readb.addActionListener(
               new ActionListener() {
                    public void actionPerformed(ActionEvent e)
                         readIt();
                         outfile += "Thickness\tAngle\n";
                         for(int j=0; j<arraythick.length; j++)
                         outfile += arraythick[j] + "\t" + arraydegree[j] + "\n";
                         output.setText( outfile );
                         getContentPane().add(scroller,BorderLayout.CENTER);
          getContentPane().add(readb,BorderLayout.SOUTH);
     private void openFile( )
     try {
          FileReader file1 = new FileReader("mydata.txt");
     BufferedReader bfile1 = new BufferedReader(file1);
     catch ( IOException e ) {
     JOptionPane.showMessageDialog( this,
     "File does not exist",
     "Invalid File Name",
     JOptionPane.ERROR_MESSAGE );
     private void closeFile()
     try {
     bfile1.close();
     catch ( IOException ioe ) {
     JOptionPane.showMessageDialog( this,
     "Error closing file",
     "Error", JOptionPane.ERROR_MESSAGE );
     System.exit( 1 );
     public void readIt() {     
     String srecord = null;
     openFile();
     try {  
     srecord = new String();
          int index = 0;
     while ( (srecord = bfile1.readLine()) != null ) {
          StringTokenizer tokens = new StringTokenizer( srecord );
          arraythick[index+1] = Double.parseDouble(tokens.nextToken());
          arraydegree[index+1] = Double.parseDouble(tokens.nextToken());
          catch (IOException e) {
     // catch possible io errors from readLine()
     System.out.println("Uh oh, got an IOException error!");
     e.printStackTrace();
public static void main( String args[] )
final ReadFile app = new ReadFile();
app.setSize(300, 300);
app.addWindowListener(
new WindowAdapter() {
public void windowClosing( WindowEvent e )
app.closeFile();
          System.exit( 0 );
app.show();