ASE 암호화, 복호화

sample code :

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.util.Base64;

public class AESEncryptionExample {

    private static final String ALGORITHM = "AES";
    private static final String KEY = "my-secure-key-123";

    public static String encrypt(String input) throws Exception {
        SecretKeySpec keySpec = new SecretKeySpec(KEY.getBytes(StandardCharsets.UTF_8), ALGORITHM);
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        cipher.init(Cipher.ENCRYPT_MODE, keySpec);
        byte[] encrypted = cipher.doFinal(input.getBytes(StandardCharsets.UTF_8));
        return Base64.getEncoder().encodeToString(encrypted);
    }

    public static String decrypt(String input) throws Exception {
        SecretKeySpec keySpec = new SecretKeySpec(KEY.getBytes(StandardCharsets.UTF_8), ALGORITHM);
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        cipher.init(Cipher.DECRYPT_MODE, keySpec);
        byte[] decoded = Base64.getDecoder().decode(input);
        byte[] decrypted = cipher.doFinal(decoded);
        return new String(decrypted, StandardCharsets.UTF_8);
    }

    public static void main(String[] args) throws Exception {
        String plainText = "This is a secret message!";
        String encryptedText = encrypt(plainText);
        String decryptedText = decrypt(encryptedText);
        System.out.println("Plain Text: " + plainText);
        System.out.println("Encrypted Text: " + encryptedText);
        System.out.println("Decrypted Text: " + decryptedText);
    }
}

 

output : 

Plain Text: This is a secret message!
Encrypted Text: S/VzTbT3NDq3Zm7xnZoAYA==
Decrypted Text: This is a secret message!