Sha256: 8cc736d342f1e854d1b950737bf8bb44fe5a15af313dbcb91e9e1af8915bc48f
Contents?: true
Size: 1.62 KB
Versions: 147
Compression:
Stored size: 1.62 KB
Contents
import java.util.ArrayList;
import java.util.List;
public class Atbash {
private static final int GROUP_SIZE = 5;
private static final String PLAIN = "abcdefghijklmnopqrstuvwxyz";
private static final String CIPHER = "zyxwvutsrqponmlkjihgfedcba";
public static String encode(String input) {
String encoded = stripInvalidCharacters(input).toLowerCase();
String cyphered = "";
for (char c : encoded.toCharArray()) {
cyphered += applyCipher(c);
}
return splitIntoFiveLetterWords(cyphered);
}
public static String decode(String input) {
String encoded = stripInvalidCharacters(input).toLowerCase();
String deciphered = "";
for (char c : encoded.toCharArray()) {
deciphered += applyCipher(c);
}
return deciphered;
}
private static String stripInvalidCharacters(String input) {
String filteredValue = "";
for (char c : input.toCharArray()) {
if (Character.isLetterOrDigit(c)) {
filteredValue += c;
}
}
return filteredValue;
}
private static char applyCipher(char input) {
int idx = PLAIN.indexOf(input);
return idx >= 0 ? CIPHER.toCharArray()[idx] : input;
}
private static String splitIntoFiveLetterWords(String value) {
List<String> words = new ArrayList<>();
for (int i = 0; i < value.length(); i += GROUP_SIZE) {
words.add(i + GROUP_SIZE <= value.length() ? value.substring(i, i + GROUP_SIZE) : value.substring(i));
}
return String.join(" ", words);
}
}
Version data entries
147 entries across 147 versions & 1 rubygems