import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Scanner;

/**
   This program encrypts a file, using the Caesar cipher.
*/
public class CaesarEncryptor
{  
   public static void main(String[] args)
   {  
      Scanner in = new Scanner(System.in);
      try
      {  
         System.out.print("Input file: ");
         String inFile = in.next();
         System.out.print("Output file: ");
         String outFile = in.next();
         System.out.print("Encryption key: ");
         int key = in.nextInt();
                 
         InputStream inStream = new FileInputStream(inFile);
         OutputStream outStream = new FileOutputStream(outFile);

         CaesarCipher cipher = new CaesarCipher(key);
         cipher.encryptStream(inStream, outStream);

         inStream.close();
         outStream.close();
      }
      catch (IOException exception)
      {  
         System.out.println("Error processing file: " + exception);
      }
   }
}