CODER AND DE-CODER

				
//**************************************
// Name: CODER AND DE-CODER
// Description:This code is written for the main purpose of security. It can code a sentence to an other string for some specific number and can be de coded back only if the coded form along with the secret number are entered.
// By: Suyash Bhatt
//
// Inputs:1-) name of the string to be coded or decoded, according to the user.
2-) Secret number for coding
3-) user friendly therefor continue or not....
//
// Returns:coded or decoded form of the given string.
//
// Assumes:Its totally a user friendly progrm so user don't need to know anything except running the program.
//
// Side Effects:enter a lesser secret value....
//
//This code is copyrighted and has// limited warranties.Please see http://www.Planet-Source-Code.com/vb/scripts/ShowCode.asp?txtCodeId=5277&lngWId=2//for details.//**************************************

import java.io.* ;
import java.lang.* ;
class testy
{
public String coding (String s2, int num2)
{
String cod="" ;
String s1=s2 ;
int num1=num2 ;
int len=s1.length () ;
int arr[] = new int [len] ;
int check=2 ;
for (int c=0; c<len; c++ ) 
{
char ch=s1.charAt(c) ;
arr[c]=(int)ch;
}
for(int c1=0 ; c1<len; c1++ )
{
if (arr[c1]<=(127-num1)) 
arr[c1]=arr[c1]+num1 ;
else
if (arr[c1]>(127-num1))
{
System.out.println (" THE CODING IS NOT POSSIBLE FOR THIS NUMBER...... ") ;
System.out.println (" PLEASE ENTER A LOWER NUMBER . ") ;
System.out.println (".............................") ;
System.out.println (".............................") ;
System.out.println () ;
System.out.println () ;
check=5 ;
break ;
}
}
if (check==2)
{
System.out.println () ;
for (int c2=0; c2<len; c2++) 
{
cod=cod+(char)arr[c2] ;
}
}
return cod ;
}
public String decoding (String s2, int num2)
{
String decod="" ;
String s1=s2 ;
int num1=num2 ;
int len=s1.length () ;
int arr[] = new int [len] ;
for (int c=0; c<len; c++ ) 
{
char ch=s1.charAt(c) ;
arr[c]=(int)ch;
}
for(int c1=0 ; c1<len; c1++ )
{
arr[c1]=arr[c1]-num1 ;
}
System.out.println () ;
for (int c2=0; c2<len; c2++) 
{decod=decod+(char)arr[c2] ;
}
return decod ;
}
public static void main (String args []) throws IOException
{
int chf=0 ;
do
{
InputStreamReader isr = new InputStreamReader (System.in) ;
BufferedReader d= new BufferedReader (isr) ;
System.out.println(" CODING OR DECODING ? for coding press 1 and for decoding press 2 ") ;
int choice = Integer.parseInt (d.readLine () ) ;
testy obj=new testy () ;
if (choice==1)
{
String cod="" ;
System.out.println ("ENTER THE STRING TO BE CODED ") ;
String codingstring=d.readLine () ;
String s1= codingstring ; 
System.out.println (" Enter the secret number between 0 and 10 for coding ") ;
int num1=Integer.parseInt (d.readLine ()) ;
String finaly=obj.coding (s1,num1) ;
if (finaly.length ()>0)
System.out.println ("the coded String is :- "+finaly);
System.out.println () ;
System.out.println () ;
System.out.println () ;
System.out.println (" DO YOU WANT TO CONTINUE (enter 1 for YES and 2 for NO) :- ") ;
chf=Integer.parseInt(d.readLine ()) ;
}
else 
if (choice==2)
{
System.out.println ("ENTER THE STRING TO BE DE-CODED ") ;
String codingstring=d.readLine () ;
String s1= codingstring ; 
System.out.println (" Enter the secret number between 0 and 10 for decoding ") ;
int num1=Integer.parseInt (d.readLine ()) ;
String finaly=obj.decoding (s1,num1) ;
if (finaly!=null)
System.out.println ("the decoded String is :- "+finaly);
System.out.println () ;
System.out.println () ;
System.out.println () ;
System.out.println (" DO YOU WANT TO CONTINUE (enter 1 for YES and 2 for NO) :- ") ;
chf=Integer.parseInt(d.readLine () ) ;
}
}while (chf==1) ;
}
}