Here is a short program which reads from a file named myList.dat and prints the lines of that file in reverse order. The file can contain a maximum of 100 lines in this example. Note the two step process for reading files. First we create a file handle of type FileReader, then we create a buffer capable of reading the from the file handle.

import javax.swing.JOptionPane;
import java.io.*;
public class Read_File
{
 public static void main( String args[] )
 {
  final int Max = 100;
  int counter = 0;
  String array[] = new String [Max];
  String line, output="";
  String file = "myList.dat";
  try
  {
//create a file handle
      FileReader file_reader = new FileReader ( file );

//open file and create an object for reading file
      BufferedReader my_buffer_reader = new BufferedReader ( file_reader );

      do 
      {
//copy one line into variable "line"
           line = my_buffer_reader.readLine();
	   if(line == null)           //we reached the end of file, so quit
	       {
	       break;
	       }
	   array[counter] = new String ( line );
	   counter++;
      }while( counter < Max );//continue until array is filled up
      my_buffer_reader.close();//close my buffer
      while (counter !=0 )//print contents in reverse order
      {
      	   counter--;
	   output+=array[counter];
	   output+='\n';
      }
      JOptionPane.showMessageDialog(null, "The file contains: \n" + output);
  }//end try
  
  catch ( FileNotFoundException someException )
  {
   System.out.println( "File not found." );
  }
  
  catch ( IOException someException )
  {
   System.out.println( someException );
  }
  
  System.exit(0);
 }//end main()
}//end class

hello
world

© Nachum Danzig December 2003