Caesar Cipher Java Code

Caesar Cipher Java Code
Caesar Cipher Decrypt Java Code
Caesar Cipher Java Program
Caesar Cipher Java Code Tutorial

Caesar cipher is one of the simplest encryption technique. It is also known as the shift cipher, Caesar's cipher, Caesar shift or Caesar's code. Caesar cipher is a type of substitution cipher. By using this cipher technique we can replace each letter in the plaintext with different one a fixed number of places up or down the alphabet. Note: The terms are explained in the order in which they are used in cryptography. Cryptography and ciphers techniques This is my code to encrypt-decrypt message using caesar cipher. Below I have shared the program to implement this algorithm in Java.: the letter after z is a, and the letter after Z is A).

Hey guys! The topic for today is how to implement Caesar Cipher in Java.
So we will learn how to encode our message using Caesar Cipher algorithm which is both simplest and easiest of all encryption algorithms.

Caesar Cipher

Caesar Cipher is named after Julius Caesar and is one of the simplest and weakest encryption algorithms.
Therefore it is used only in parts of other complex encryption algorithms making the CipherText harder to decode.

Caesar cipher or Shift Cipher is a Substitution cipher algorithm in which each letter of the plain text (message) is substituted with another letter. In this algorithm, each letter of the Plaintext is shifted a number of positions based on the Key provided.
For example:
PlainText: Hello!
Key: 3
Each letter of the plain text is shifted three times to the next letter.

H -> K
e -> h
l -> o
l -> o
o -> r
! -> !

Therefore the CipherText is: Khoor!

Point to be Noted: The cipher only encrypts letters; symbols, numbers remain unencrypted.

Code to implement Caesar Cipher in Java

Explanation of Caesar Cipher Java Program

We check if the input string consists of any special characters or numbers. If so, we print them as it is.
If we encounter a Lowercase or an Uppercase letter we add the value of the key to the ASCII value of that letter and print it.
We perform modulo 26 operations as there are 26 alphabets. So if the shift takes to the ending alphabets we are reverted back to the beginning alphabets. (i.e) in case of a shift by 3, w, x, y and z would map to z, a, b and c.

Output:

Advantages:

Simple and Easy to implement.
Uses a single Key.
Requires very few system resources.