//

// https://github.com/WelkinXie/AESCipher-Java

//

import java.security.InvalidAlgorithmParameterException;

import java.security.InvalidKeyException;

import java.security.NoSuchAlgorithmException;

import java.util.Base64;

import java.util.Base64.Decoder;

import java.util.Base64.Encoder;

import javax.crypto.BadPaddingException;

import javax.crypto.Cipher;

import javax.crypto.IllegalBlockSizeException;

import javax.crypto.NoSuchPaddingException;

import javax.crypto.spec.IvParameterSpec;

import javax.crypto.spec.SecretKeySpec;

import java.io.UnsupportedEncodingException;

public class AESCipher {

private static final String IV_STRING = "A-16-Byte-String";

private static final String charset = "UTF-8";

public static String aesEncryptString(String content, String key) throws InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException {

byte[] contentBytes = content.getBytes(charset);

byte[] keyBytes = key.getBytes(charset);

byte[] encryptedBytes = aesEncryptBytes(contentBytes, keyBytes);

Encoder encoder = Base64.getEncoder();

return encoder.encodeToString(encryptedBytes);

}

public static String aesDecryptString(String content, String key) throws InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException {

Decoder decoder = Base64.getDecoder();

byte[] encryptedBytes = decoder.decode(content);

byte[] keyBytes = key.getBytes(charset);

byte[] decryptedBytes = aesDecryptBytes(encryptedBytes, keyBytes);

return new String(decryptedBytes, charset);

}

public static byte[] aesEncryptBytes(byte[] contentBytes, byte[] keyBytes) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException {

return cipherOperation(contentBytes, keyBytes, Cipher.ENCRYPT_MODE);

}

public static byte[] aesDecryptBytes(byte[] contentBytes, byte[] keyBytes) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException {

return cipherOperation(contentBytes, keyBytes, Cipher.DECRYPT_MODE);

}

private static byte[] cipherOperation(byte[] contentBytes, byte[] keyBytes, int mode) throws UnsupportedEncodingException, NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException {

SecretKeySpec secretKey = new SecretKeySpec(keyBytes, "AES");

byte[] initParam = IV_STRING.getBytes(charset);

IvParameterSpec ivParameterSpec = new IvParameterSpec(initParam);

Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");

cipher.init(mode, secretKey, ivParameterSpec);

return cipher.doFinal(contentBytes);

}

}