/*
 * Pedantic.java
 *
 * 
 */

class Pedantic
{
    
  public static void main (String [] args) 
 { 
     String crap = "blah blah blah blah 2343";
     int length = crap.length();
     String c = crap.substring(length-4,length);
     int num = Integer.parseInt(c);
     System.out.println(num*2); //multiply by 2
  }

}

String last = "";
System.out.println("Your Received message is as following:");
while((recv_Message=buff2.readLine() )!=null){
  last = recv_Message;
  System.out.println(recv_Message);
}
 
four_characters=last.substring(last.length() - 4);
Four_characters_Integers = Integer.parseInt(four_characters);

/*
   * ped.java
   *
   * Created on 29 April 2006, 17:07
   */
import java.awt.*;
import java.io.*;
import java.util.*;
 
 
class Pedantic
{
 
   public static void main (String [] args)
   {
 
       try {
	      BufferedReader in = new BufferedReader(new FileReader("Myfile.txt"));
	      String str;
	      while ((str = in.readLine()) != null)//read in a line
	      {
 
	       int length = str.length();
	       String c = str.substring(length-4,length);
	       int num = Integer.parseInt(c);
               //System.out.println(str);
	       System.out.println(num*2); //multiply last four digit by 2
	      }
	     in.close();
        }
      catch (IOException e)
      {
 
      }
 
   }
 
}

 
package final_append;
import java.io.*;
public class CopyBytes {
static String bobSignedMsg;
static  String SUBString;
static int bobMsgLen;
static String My_Message_Length  ;
static int len;
static String recv_Message;
static String Message_Length;
static int length2;
static String c;
static int num;
public static void main(String[] args) throws IOException {
/*==========================Printing the input message========================*/
try{
FileInputStream Message_File=new FileInputStream ("C:/JBuilder4/lib/output8.txt");
BufferedReader buff=new BufferedReader(new InputStreamReader(Message_File));
String Input_Message=new String();
System.out.println("Your input message is as following:");
while((Input_Message=buff.readLine() )!=null){
// Calculating the the length of our message in unit of bits
System.out.println(Input_Message);
len += Input_Message.length();
 
}
System.out.println(len);
/*==================here we will represent message length into four characters========================================================*/
  String My_Message_Length = "" + len;
    //Confirm number of characters in the string.
    if((My_Message_Length.length() > 4)
            || (My_Message_Length.length() <= 0)){
      System.out.println("Message length error.");
      System.exit(0);
    }//end if
    //Prepend leading zeros if necessary
    if(My_Message_Length.length() == 1){
                         My_Message_Length = "000"
                              + My_Message_Length;
    }else if(My_Message_Length.length() == 2){
      My_Message_Length = "00" + My_Message_Length;
    }else if(My_Message_Length.length() == 3){
      My_Message_Length = "0" + My_Message_Length;
    }else if(My_Message_Length.length() == 1){
                        My_Message_Length = "000"
                             + My_Message_Length;
    }
    System.out.println(My_Message_Length);
 
    /*=========================Append the message length string to the=========
    ========================= previously signed message=======================*/
// create writer for file to append to
BufferedWriter out = new BufferedWriter(
new FileWriter("C:/JBuilder4/lib/output6.txt", true));
// create reader for file to append from
BufferedReader in = new BufferedReader(new FileReader("C:/JBuilder4/lib/output4.txt"));
String str;
while ((str = in.readLine()) != null) {
out.write(str);
}
in.close();
out.close();
/*=================appending the length of message to My message=====================================================*/
BufferedWriter bw = null;
 bw = new BufferedWriter(new FileWriter("C:/JBuilder4/lib/output6.txt", true));
 bw.write(My_Message_Length);
 bw.newLine();
 bw.flush();
 
//======================Sending the Message to the Receiver Side================
recv_Message = null;
FileInputStream Received_Message=new FileInputStream ("C:/JBuilder4/lib/output6.txt");
BufferedReader buff2=new BufferedReader(new InputStreamReader(Received_Message));
System.out.println("Your Received message is as following:");
String four_characters = null;
int Four_characters_Integers;
while((recv_Message=buff2.readLine() )!=null){
// Calculating the the length of our message in unit of bits
System.out.println(recv_Message);
four_characters = recv_Message.substring(recv_Message.length() - 4);
Four_characters_Integers = Integer.parseInt(four_characters);
System.out.println("last four characters are:" + four_characters);
//length2 += recv_Message.length();
//SUBString = recv_Message.substring(recv_Message.length() - 4);
}
} catch (FileNotFoundException e) {
System.out.println("Cannot find file MyFile.txt \n" + e);
} catch (IOException e) {
System.out.println("IOException " + e);
} catch (NumberFormatException e) {
System.out.println("Not a number on the last 4 characters : " + recv_Message + "\n" + e);