//FileClassDemo.java

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

public class FileClassDemo
{
    public static void main(String[] args)
    {
        System.out.print("Enter file name: ");
        Scanner keyboard = new Scanner(System.in);
        String fileName = keyboard.next();

        File fileObject = new File(fileName);
        boolean fileOK = false;
        while (!fileOK)
        {
            if (!fileObject.exists())
                System.out.println("No such file");
            else if (!fileObject.canRead())
                System.out.println("That file is not readable.");
            else
                fileOK = true;

            if (!fileOK)
            {
                System.out.println("Enter file name again:");
                fileName = keyboard.next();
                fileObject = new File(fileName);
            }
        }

        Scanner inputStream = null;
        System.out.println("The file " + fileName
            + "\ncontains the following lines\n");
        try
        {
            inputStream = new Scanner(new File(fileName));
        }
        catch (FileNotFoundException e)
        {
            System.out.println("Error opening the file " + fileName);
            System.exit(0);
        }

        while (inputStream.hasNextLine())
        {
            String line = inputStream.nextLine();
            System.out.println(line);
        }

        inputStream.close();
    }
}