JF-Exams-SongEncryption

package com.company;

import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class SongEncryption {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        String input = sc.nextLine();

        String regex = "^(?<artist>[A-Z][a-z ']*)(?<dots>:)(?<song>[A-Z ]*)$";

        Pattern pattern = Pattern.compile(regex);

        StringBuilder sbArtist = new StringBuilder();
        StringBuilder sbSong = new StringBuilder();

        while (!input.equalsIgnoreCase("end")) {
            Matcher matcher = pattern.matcher(input);

            if (matcher.find()) {

                String artist = matcher.group(1);
                String song = matcher.group(3);
                int key = artist.length();

                for (int i = 0; i < artist.length(); i++) {
                    char c = artist.charAt(i);
                    if ((char) c == 32 || ((char) c == 39)) {
                        sbArtist.append(c);
                    } else if ((char) c == 58) {
                        sbArtist.append('@');
                    } else {
                        if ((char) (c + key) > 122) {
                            char newChar = (char) (c + key - 26);
                            sbArtist.append(newChar);
                        } else if ((char) (c + key) < 123 && (char) (c + key) > 96) {
                            sbArtist.append((char) (c + key));
                        } else if ((char) (c + key) > 90) {
                            char newChar = (char) (c + key - 26);
                            sbArtist.append(newChar);
                        } else if ((char) (c + key) < 91) {
                            char newChar = (char) (c + key);
                            sbArtist.append(newChar);
                        }
                    }
                }
                for (int i = 0; i < song.length(); i++) {
                    char c = song.charAt(i);
                    if ((char) c == 32 || ((char) c == 39)) {
                        sbSong.append(c);
                    } else if ((char) c == 58) {
                        sbSong.append('@');
                    } else {
                        if ((char) (c + key) > 122) {
                            char newChar = (char) (c + key - 26);
                            sbSong.append(newChar);
                        } else if ((char) (c + key) < 123 && (char) (c + key) > 96 && c > 96) {
                            sbSong.append((char) (c + key));
                        } else if ((char) (c + key) < 123 && (char) (c + key) > 96 && c < 96) {
                            sbSong.append((char) (c + key - 26));
                        } else if ((char) (c + key) > 90) {
                            char newChar = (char) (c + key - 26);
                            sbSong.append(newChar);
                        } else if ((char) (c + key) < 91) {
                            char newChar = (char) (c + key);
                            sbSong.append(newChar);
                        }
                    }
                }
                System.out.printf("Successful encryption: %s@%s%n", sbArtist, sbSong);
            } else {
                System.out.println("Invalid input!");
            }

            input = sc.nextLine();
            sbArtist = new StringBuilder();
            sbSong = new StringBuilder();
        }
    }
}