/*

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package Algorithm;

/**

*

* @author qngnhat

*/

import java.io.UnsupportedEncodingException;

import java.security.MessageDigest;

import java.security.NoSuchAlgorithmException;

import java.util.Arrays;

import java.util.Base64;

import javax.crypto.Cipher;

import javax.crypto.spec.SecretKeySpec;

public class AES {

private static SecretKeySpec secretKey;

private static byte[] key;

public static void main(String[] args) {

final String secretKey = "ssshhhhhhhhhhh!!!!";

String originalString = "howtodoinjava.com";

String encryptedString = AES.encrypt(originalString, secretKey);

String decryptedString = AES.decrypt(encryptedString, secretKey);

System.out.println(originalString);

System.out.println(encryptedString);

System.out.println(decryptedString);

}

public static void setKey(String myKey) {

MessageDigest sha = null;

try {

key = myKey.getBytes("UTF-8");

sha = MessageDigest.getInstance("SHA-1");

key = sha.digest(key);

key = Arrays.copyOf(key, 16);

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

} catch (NoSuchAlgorithmException e) {

e.printStackTrace();

} catch (UnsupportedEncodingException e) {

e.printStackTrace();

}

}

public static String encrypt(String strToEncrypt, String secret) {

try {

setKey(secret);

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

cipher.init(Cipher.ENCRYPT_MODE, secretKey);

return Base64.getEncoder().encodeToString(cipher.doFinal(strToEncrypt.getBytes("UTF-8")));

} catch (Exception e) {

System.out.println("Error while encrypting: " + e.toString());

}

return null;

}

public static String decrypt(String strToDecrypt, String secret) {

try {

setKey(secret);

Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5PADDING");

cipher.init(Cipher.DECRYPT_MODE, secretKey);

return new String(cipher.doFinal(Base64.getDecoder().decode(strToDecrypt)));

} catch (Exception e) {

System.out.println("Error while decrypting: " + e.toString());

}

return null;

}

}