JAVA单向加密(MD5，SHA，MAC)

转自：http://fcm915.javaeye.com/blog/401562

JAVA单向加密(MD5，SHA，MAC)

具体代码如下：

import java.security.MessageDigest;

import javax.crypto.KeyGenerator;
import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

/** *//**
* 加密（主要有：MD4,SHA,MAC）
*
* @author kinkding
* @history 2009-6-3
*/
public class MyEncrypt {
/** *//** MD5 加密 */
public static byte[] encryptMD5(byte[] data) throws Exception {
MessageDigest md5 = MessageDigest.getInstance("MD5");
md5.update(data);
return md5.digest();
}

/** *//** SHA 加密 */
public static byte[] encryptSHA(byte[] data) throws Exception {
MessageDigest sha = MessageDigest.getInstance("SHA");
sha.update(data);
return sha.digest();
}

/** *//** 取得HMAC密钥 */
public static String getMacKey() throws Exception {
KeyGenerator keyGenerator = KeyGenerator.getInstance("HmacMD5");
SecretKey secretKey = keyGenerator.generateKey();
return new BASE64Encoder().encode(secretKey.getEncoded());
}

/** *//** 执行加密 */
public static byte[] encryptHMAC(byte[] data, String key) throws Exception {
byte[] bkey = new BASE64Decoder().decodeBuffer(key);
SecretKey secretKey = new SecretKeySpec(bkey, "HmacMD5");
Mac mac = Mac.getInstance(secretKey.getAlgorithm());
mac.init(secretKey);
return mac.doFinal(data);
}

private static String toHex(byte[] buffer) {
StringBuffer sb = new StringBuffer(buffer.length * 3);
for (int i = 0; i < buffer.length; i++) {
sb.append(Character.forDigit((buffer[i] & 0xf0) >> 4, 16));
sb.append(Character.forDigit(buffer[i] & 0x0f, 16));
}
return sb.toString();
}

public static void main(String[] args) {
String msg = "生活真好^_^";
byte[] data = msg.getBytes();
try {
System.out.println("msg:" + msg);
System.out.println("md5:" + toHex(encryptMD5(data)));
System.out.println("sha:" + toHex(encryptSHA(data)));
String key = getMacKey();
System.out.println("mac key:" + key);
System.out.println("mac:" + toHex(encryptHMAC(data, key)));
} catch (Exception e) {
e.printStackTrace();
}

}
}

运行效果如下：

msg:生活真好^_^
md5:e0649dfaef57789734e920c7ecb9c4ea
sha:a4bd855836de26b2323778b797629fed4416f12f
mac key:zBPe28oho2H84+Mg8mF4abpd0MQvdjgqgFdX4hmUQQbOGnX1aFq/oQnogsHVIczgx1AZ1s2/ncPz
tBQIGLZUnw==
mac:87f4140161ad43797059e85dd9962897