ShowFile.java

package chapter13;

import java.io.*;

/*
     Display a text file
     To use this program,specify the name
     of the file that you want to see.
     For example, to see a file called TEST.txt
     use the following command line.
     Java ShowFile TEST.txt
*/
public class ShowFile {
    public static void main(String[] args) {
        int i;

        FileInputStream fin;
        //First confirm that a file name has been specified.
        if (args.length != 1) {
            System.out.println("Usage: ShowFile fileName");
            return;
        }
        //Attempt to open the file
        try {
            fin = new FileInputStream(args[0]);

        } catch (FileNotFoundException e) {
            System.out.println("Cannot open file");
            return;
        }

        //At this point , the file is open and can be read
        //The following read characters until EOF is encountered.
        try {
            do {
                i = fin.read();
                if (i != -1) System.out.println((char) i);

            } while (i != -1);
        } catch (IOException e) {
            System.out.println("Error Reading File");
        }
        //Close the file
        try {
            fin.close();
        } catch (IOException e) {
            System.out.println("Error Closing File");
        }
    }
}