java中的仿射密码，也加密整数

Question

private static int firstKey = 5;
private static int secondKey = 19;
private static int module = 26;
public static void main(String[] args) {
    String input = "abcdefghijklmnopqrstuvwxyz";
    String cipher = encrypt(input);
    String deciphered = decrypt(cipher);
    System.out.println("Source:    " + input);
    System.out.println("Encrypted: " + cipher);
    System.out.println("Decrypted: " + deciphered);
}
static String encrypt(String input) {
    StringBuilder builder = new StringBuilder();
    for (int in = 0; in < input.length(); in++) {
        char character = input.charAt(in);
       // if (Character.isLetter(character)) {
            character = (char) ((firstKey * (character - 'a') + secondKey) % module + 'a');
        //}
        builder.append(character);
    }
    return builder.toString();
}
static String decrypt(String input) {
    StringBuilder builder = new StringBuilder();
    // compute firstKey^-1 aka "modular inverse"
    BigInteger inverse = BigInteger.valueOf(firstKey).modInverse(BigInteger.valueOf(module));
    // perform actual decryption
    for (int in = 0; in < input.length(); in++) {
        char character = input.charAt(in);
       // if (Character.isLetter(character)) {
            int decoded = inverse.intValue() * (character - 'a' - secondKey + module);
            character = (char) (decoded % module + 'a');
        //}
        builder.append(character);
    }
    return builder.toString();
}

我从这个网站本身得到了这个代码但是上面的代码并没有对整数进行解码..请帮忙

以上是我从这个网站得到的代码。但这不会解密整数。请帮忙。

Answer 1

我添加了另外两个功能，用于加密和解密有效的整数。当您想要加密、解密整数时，您可以使用它们，当您想要对小写字母进行 enc/dec 时，可以使用前面的函数

//法典

import java.math.BigInteger;
public class main{
    private static int firstKey = 5;
    private static int secondKey = 19;
    private static int module = 26;
    public static void main(String[] args) {
        String input = "abcdefghijklmnopqrstuvwxyz";
        String cipher = encrypt(input);
        String deciphered = decrypt(cipher);
        System.out.println("Source:    " + input);
        System.out.println("Encrypted: " + cipher);
        System.out.println("Decrypted: " + deciphered);
        System.out.println("n");
        //for Integer
        String input1 = "826429837598327598327549832";
        String cipher1 = encryptInt(input1);
        String deciphered1 = decryptInt(cipher1);
        System.out.println("Source:    " + input1);
        System.out.println("Encrypted: " + cipher1);
        System.out.println("Decrypted: " + deciphered1);
    }
    static String encrypt(String input) {
        StringBuilder builder = new StringBuilder();
        for (int in = 0; in < input.length(); in++) {
            char character = input.charAt(in);
           // if (Character.isLetter(character)) {
                character = (char) ((firstKey * (character - 'a') + secondKey) % module + 'a');
            //}
            builder.append(character);
        }
        return builder.toString();
    }
    static String decrypt(String input) {
        StringBuilder builder = new StringBuilder();
        // compute firstKey^-1 aka "modular inverse"
        BigInteger inverse = BigInteger.valueOf(firstKey).modInverse(BigInteger.valueOf(module));
        // perform actual decryption
        for (int in = 0; in < input.length(); in++) {
            char character = input.charAt(in);
           // if (Character.isLetter(character)) {
                int decoded = inverse.intValue() * (character - 'a' - secondKey + module);
                character = (char) (decoded % module + 'a');
            //}
            builder.append(character);
        }
        return builder.toString();
    }
    //ENCRIPTION DECRIPTION FOR INTEGERS
    static String encryptInt(String input) {
        StringBuilder builder = new StringBuilder();
        for (int in = 0; in < input.length(); in++) {
            char character = input.charAt(in);
           // if (Character.isLetter(character)) {
                character = (char) ((firstKey * (character - '0') + secondKey) % module + '0');
            //}
            builder.append(character);
        }
        return builder.toString();
    }
    static String decryptInt(String input) {
        StringBuilder builder = new StringBuilder();
        // compute firstKey^-1 aka "modular inverse"
        BigInteger inverse = BigInteger.valueOf(firstKey).modInverse(BigInteger.valueOf(module));
        // perform actual decryption
        for (int in = 0; in < input.length(); in++) {
            char character = input.charAt(in);
           // if (Character.isLetter(character)) {
                int decoded = inverse.intValue() * (character - '0' - secondKey + module);
                character = (char) (decoded % module + '0');
            //}
            builder.append(character);
        }
        return builder.toString();
    }
}