Java AES Encrypt & Decrypt Example(加解密)

范例程式

//欲加密的字串
String msg = "This is a message.";
System.out.println("原始字串："+new String(msg));
//设定要使用的加密演算法
KeyGenerator keyG = KeyGenerator.getInstance("AES");
//设定key的长度
keyG.init(256);
//产生SecretKey
SecretKey secuK = keyG.generateKey();
//取得要用来加密的key(解密也需使用这把key)
byte[] key = secuK.getEncoded();
System.out.println("key："+new String(key));
SecretKeySpec spec = new SecretKeySpec(key, "AES");
Cipher cipher = Cipher.getInstance("AES");
//设定为加密模式
cipher.init(Cipher.ENCRYPT_MODE, spec);
//将字串加密，并取得加密后的资料
byte[] encryptData = cipher.doFinal(msg.getBytes());
System.out.println("加密后字串："+new String(encryptData));

//使用刚刚用来加密的key进行解密
spec = new SecretKeySpec(key, "AES");
cipher = Cipher.getInstance("AES");
//设定为解密模式
cipher.init(Cipher.DECRYPT_MODE, spec);
byte[] original = cipher.doFinal(encryptData);
System.out.println("解密后字串："+new String(original));

输出结果

原始字串：This is a message.
key：�U{� jPk ���@7 .�A@��&]W LK���ݣ
加密后字串：��� � ����tl7Q U!���d�{4R) �� .
解密后字串：This is a message.