KeyGenerator 的初始化步骤，可能导致使用比推荐的密钥更小的密钥：... final String CIPHER_INPUT = "123456ABCDEFG"; KeyGenerator keyGenerator = KeyGenerator.getInstance("AES"); SecretKey secretKey = keyGenerator.generateKey(); byte[] byteKey = secretKey.getEncoded(); ....
解决方案：
KeyGenerator generator = KeyGenerator.getInstance("DES");
SecureRandom random = new SecureRandom();
generator.init(random);//初始化秘钥生成器
SecretKey key = generator.generateKey();//生成密钥
Mac mac = Mac.getInstance("HmacSHA256");//得到此密钥的Mac对象
Weak Encryption: Missing Required Step
原文：https://www.cnblogs.com/zhouj850/p/13181342.html