1  import java.io.File;

  2  import java.io.FileInputStream;

  3  import java.io.FileOutputStream;

  4  import java.io.InputStream;

  5  import java.io.IOException;

  6  import java.io.OutputStream;

  7  import java.util.Scanner;

  8  

  9  /**

 10     This program encrypts a file, using the Caesar cipher.

 11  */

 12  public class CaesarEncryptor

 13  {  

 14     public static void main(String[] args)

 15     {  

 16        Scanner in = new Scanner(System.in);

 17        try

 18        {  

 19           System.out.print("Input file: ");

 20           String inFile = in.next();

 21           System.out.print("Output file: ");

 22           String outFile = in.next();

 23           System.out.print("Encryption key: ");

 24           int key = in.nextInt();

 25                   

 26           InputStream inStream = new FileInputStream(inFile);

 27           OutputStream outStream = new FileOutputStream(outFile);

 28  

 29           CaesarCipher cipher = new CaesarCipher(key);

 30           cipher.encryptStream(inStream, outStream);

 31  

 32           inStream.close();

 33           outStream.close();

 34        }

 35        catch (IOException exception)

 36        {  

 37           System.out.println("Error processing file: " + exception);

 38        }

 39     }

 40  }

 41  

 42