Android studio for some reason can not allow this method. Below is the class itself:

package com.example.chernovik; import android.util.Base64; import javax.crypto.Cipher; import javax.crypto.spec.IvParameterSpec; import javax.crypto.spec.SecretKeySpec; public class AesCrypto { String key = "0123456789abcdef"; // 128 bit key String initVector = "abcdef9876543210"; // 16 bytes IV, it is recommended to use a different random IV for every message! private static String CIPHER_NAME = "AES/CBC/PKCS5PADDING"; private static int CIPHER_KEY_LEN = 16; //128 bits /** * Encrypt data using AES Cipher (CBC) with 128 bit key * * @param key - key to use should be 16 bytes long (128 bits) * @param iv - initialization vector * @param data - data to encrypt * @return encryptedData data in base64 encoding with iv attached at end after a : */ public static String encrypt(String key, String iv, String data) { try { IvParameterSpec ivSpec = new IvParameterSpec(iv.getBytes("UTF-8")); SecretKeySpec secretKey = new SecretKeySpec(fixKey(key).getBytes("UTF-8"), "AES"); Cipher cipher = Cipher.getInstance(AesCrypto.CIPHER_NAME); cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivSpec); byte[] encryptedData = cipher.doFinal((data.getBytes())); String encryptedDataInBase64 = Base64.getEncoder().encodeToString(encryptedData); String ivInBase64 = Base64.getEncoder().encodeToString(iv.getBytes("UTF-8")); return encryptedDataInBase64 + ":" + ivInBase64; } catch (Exception ex) { throw new RuntimeException(ex); } } private static String fixKey(String key) { if (key.length() < AesCrypto.CIPHER_KEY_LEN) { int numPad = AesCrypto.CIPHER_KEY_LEN - key.length(); for (int i = 0; i < numPad; i++) { key += "0"; //0 pad to len 16 bytes } return key; } if (key.length() > AesCrypto.CIPHER_KEY_LEN) { return key.substring(0, CIPHER_KEY_LEN); //truncate to 16 bytes } return key; } /** * Decrypt data using AES Cipher (CBC) with 128 bit key * * @param key - key to use should be 16 bytes long (128 bits) * @param data - encrypted data with iv at the end separate by : * @return decrypted data string */ public static String decrypt(String key, String data) { try { String[] parts = data.split(":"); IvParameterSpec iv = new IvParameterSpec(Base64.getDecoder().decode(parts[1])); SecretKeySpec secretKey = new SecretKeySpec(key.getBytes("UTF-8"), "AES"); Cipher cipher = Cipher.getInstance(AesCrypto.CIPHER_NAME); cipher.init(Cipher.DECRYPT_MODE, secretKey, iv); byte[] decodedEncryptedData = Base64.getDecoder().decode(parts[0]); byte[] original = cipher.doFinal(decodedEncryptedData); return new String(original); } catch (Exception ex) { throw new RuntimeException(ex); } } }

    1 answer 1

    You are importing android.util.Base64 , and trying to use it as java.util.Base64 . Replace Base64.getEncoder().encodeToString(encryptedData) with Base64.encodeToString(encryptedData, Base64.DEFAULT) .