Question

Rules for this Assignment:

There are 2 classes required for this project:

• Encryption (the primary class containing your main() method and the retrieval of the message)
• EncryptionProcedures (where your code regarding the encryption method of that message will be located)

Separation of code will be paramount in order to produce a proper and legible file. This will require that you analyse the problem and separate it into multiple tasks. Each task should then be represented by its own function.

The methods you define in the EncryptionProcedures class should be static.

Files to submit

               In a properly developed project, all your code should be located in 2 java files, Encryption.java and EncryptionProcedures.java. You will need to submit those 2 files.

               Additionally, a WORD document should also be submitted. In this document, you will explain the validity or invalidity of defining the methods in the EncryptionProcedures class as static. (minimum explanation, 5 lines)

Project Description

               The goal of the project is to be able to retrieve an input from the console, encrypt it according to specifications that will be described below, and display the result.

               The user input can be a single word, or an entire sentence (on a single line).

Specifications

private static final String[] arrPeriodicTableValues = {"h", "he", "li", "be", "b", "c", "n", "o", "f", "ne", "na", "mg", "al", "si", "p", "s", "cl", "ar", "k", "ca", "sc", "ti", "v", "cr", "mn", "fe", "co", "ni", "cu", "zn", "ga", "ge", "as", "se", "br", "kr", "rb", "sr", "y", "zr", "nb", "mo", "tc", "ru", "rh", "pd", "ag", "cd", "in", "sn", "sb", "te", "i", "xe", "cs", "ba", "la", "ce", "pr", "nd", "pm", "sm", "eu", "gd", "tb", "dy", "ho", "er", "tm", "yb", "lu", "hf", "ta", "w", "re", "os", "ir", "pt", "au", "hg", "tl", "pb", "bi", "po", "at", "rn", "fr", "ra", "ac", "th", "pa", "u", "np", "pu", "am", "cm", "bk", "cf", "es", "fm", "md", "no", "lr", "rf", "db", "sg", "bh", "hs", "mt", "ds", "rg", "cn", "nh", "fl", "mc", "lv", "ts", "og"};

               The preceding code represents all the elements of the periodic table in the form of an Array. The index of each element can be used to reference its atomic number. This instruction can be included in your code for use in this assignment.

               The encryption procedure will be a specific 1 and follow a strict set of rules in order to be properly implemented. The primary method will be called periodicEncrypt.

               Here is the overall description of the procedure to follow in order to accomplish a proper encryption in this case:

1. Go through the original string from left to right
2. Look at the first 2 characters
3. Verify if those 2 characters match 1 of the elements in the periodic table
   1. If it does, use the atomic number as a replacement for those 2 characters
   2. If it doesn’t, go back and look at just 1 character
      1. Verify if that character matches 1 of the elements in the periodic table
         1. If it does, use the atomic number as a replacement for that character
         2. If it doesn’t, leave that character unchanged
4. Repeat the process until you reach the end of the original string
5. Display the encrypted String

Answer 1

Here is needed java code. (Please see screenshots given below to better understand code.)

EncryptionProcedures.java:

public class EncryptionProcedures {
    private static final String[] arrPeriodicTableValues = { "h", "he", "li", "be", "b", "c", "n", "o", "f", "ne", "na",
            "mg", "al", "si", "p", "s", "cl", "ar", "k", "ca", "sc", "ti", "v", "cr", "mn", "fe", "co", "ni", "cu",
            "zn", "ga", "ge", "as", "se", "br", "kr", "rb", "sr", "y", "zr", "nb", "mo", "tc", "ru", "rh", "pd", "ag",
            "cd", "in", "sn", "sb", "te", "i", "xe", "cs", "ba", "la", "ce", "pr", "nd", "pm", "sm", "eu", "gd", "tb",
            "dy", "ho", "er", "tm", "yb", "lu", "hf", "ta", "w", "re", "os", "ir", "pt", "au", "hg", "tl", "pb", "bi",
            "po", "at", "rn", "fr", "ra", "ac", "th", "pa", "u", "np", "pu", "am", "cm", "bk", "cf", "es", "fm", "md",
            "no", "lr", "rf", "db", "sg", "bh", "hs", "mt", "ds", "rg", "cn", "nh", "fl", "mc", "lv", "ts", "og" };

    /**
     * Convert the given string to encrypted text using periodic table values
     * 
     * @param str
     * @return encryptedText
     */
    public static String periodicEncrypt(String str) {
        // to build encrypted text string
        StringBuilder encryptedText = new StringBuilder("");

        // Loop through input string
        int i = 0;
        while (str.length() > i) {
            // getting periodic index (atomic value) for 2 chars
            int periodicIndex = EncryptionProcedures.getPeriodicIndex(str.substring(i, i + 2));

            if (periodicIndex != -1) {
                // If found then append the index to encryptedText
                encryptedText.append(Integer.toString(periodicIndex));
                i += 2;
            } else {
                // Get periodic index for 1 char
                periodicIndex = EncryptionProcedures.getPeriodicIndex(str.substring(i, i + 1));

                if (periodicIndex != -1) {
                    // If found append index to encrypted text
                    encryptedText.append(Integer.toString(periodicIndex));
                } else {
                    // append the character to encryptedText
                    encryptedText.append(str.charAt(i));
                }
                i++;
            }
        }

        // Convert encryptedText to string and return
        return encryptedText.toString();
    }

    /**
     * Gets the periodic index (atomic value) for given string
     * 
     * @param ch
     * @return index
     */
    private static int getPeriodicIndex(String ch) {
        // loop through all the values in periodic table
        for (int i = 0; i < EncryptionProcedures.arrPeriodicTableValues.length; i++) {
            if (ch.equals(EncryptionProcedures.arrPeriodicTableValues[i])) {
                // If string found then return index of string
                return i;
            }
        }

        // If not found return -1
        return -1;
    }
}

Encryption.java

import java.util.Scanner;

public class Encryption {
    static Scanner scan = new Scanner(System.in);

    public static void main(String[] args) {
        System.out.print("Enter a string: ");
        String plainText = scan.next();

        System.out.println("Encrypted Text: " + EncryptionProcedures.periodicEncrypt(plainText));
    }
}

Output: