Java MD5Utils
Java MD5Utils
/** * <html> * <body> * <P> Copyright 1994 JsonInternational</p> * <p> All rights reserved.</p> * <p> Created on 19941115</p> * <p> Created by Jason</p> * </body> * </html> */ package cn.ucaner.alpaca.framework.utils.encrypt; import java.math.BigInteger; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import org.apache.commons.lang3.StringUtils; /** * @Package:cn.ucaner.alpaca.framework.utils.encrypt * @ClassName:MD5Utils * @Description: <p> MD5加密工具 By Jason </p> * @Author: - Jason * @CreatTime:2018年5月24日 下午9:40:31 * @Modify By: * @ModifyTime: 2018年5月24日 * @Modify marker: * @version V1.0 */ class MD5Utils { protected final static String MD5_KEY = "MD5"; protected final static String SHA_KEY = "SHA1"; /** * @param value * @param key * @return */ protected static String encrypt(String value,String key) { try { // 拿到一个MD5转换器(如果想要SHA1参数换成”SHA1”) MessageDigest messageDigest = MessageDigest.getInstance(key); // 输入的字符串转换成字节数组 byte[] inputByteArray = value.getBytes(); // inputByteArray是输入字符串转换得到的字节数组 messageDigest.update(inputByteArray); // 转换并返回结果,也是字节数组,包含16个元素 byte[] resultByteArray = messageDigest.digest(); // 字符数组转换成字符串返回 return byteArrayToHex(resultByteArray); } catch (NoSuchAlgorithmException e) { return null; } } /** * 字节数组转换为hex * @param byteArray * @return */ private static String byteArrayToHex(byte[] byteArray) { // 首先初始化一个字符数组,用来存放每个16进制字符 char[] hexDigits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9','A', 'B', 'C', 'D', 'E', 'F' }; // new一个字符数组,这个就是用来组成结果字符串的(解释一下:一个byte是八位二进制,也就是2位十六进制字符(2的8次方等于16的2次方)) char[] resultCharArray = new char[byteArray.length * 2]; // 遍历字节数组,通过位运算(位运算效率高),转换成字符放到字符数组中去 int index = 0; for (byte b : byteArray) { resultCharArray[index++] = hexDigits[b >>> 4 & 0xf]; resultCharArray[index++] = hexDigits[b & 0xf]; } // 字符数组组合成字符串返回 return new String(resultCharArray); } /** * 获得16位的加密字符 * @param str * @return * @throws NoSuchAlgorithmException */ public static String getMd5String16(String str) throws NoSuchAlgorithmException { String md5str = getMd5String32(str).substring(8); return md5str.substring(0, md5str.length() - 8); } /** * 获得24位的MD5加密字符 * @param str * @return * @throws NoSuchAlgorithmException */ public static String getMd5String24(String str) throws NoSuchAlgorithmException { String md5str = getMd5String32(str).substring(4); return md5str.substring(0, md5str.length() - 4); } /** * 获得32位的MD5加密算法 * @param str * @return * @throws NoSuchAlgorithmException */ public static String getMd5String32(String str) throws NoSuchAlgorithmException { MessageDigest md = MessageDigest.getInstance("MD5"); md.update(str.getBytes()); byte b[] = md.digest(); int i; StringBuffer buf = new StringBuffer(); for (int offset = 0; offset < b.length; offset++) { i = b[offset]; if (i < 0) i += 256; if (i < 16) buf.append("0"); buf.append(Integer.toHexString(i)); } return buf.toString(); } /** * 获取MD5密码 * @param password * @param salt * @return * @throws NoSuchAlgorithmException */ public static String getMD5Pwd(String password, String salt) throws NoSuchAlgorithmException { String result = null; if (StringUtils.isNotBlank(salt)) { result = getMD5(getMD5(password) + salt); } else { result = getMD5(password); } return result; } /** * 获取MD5加密数据 * @param input * @return * @throws NoSuchAlgorithmException */ public static String getMD5(String input) throws NoSuchAlgorithmException { String result = input; if (input != null) { MessageDigest md = MessageDigest.getInstance("MD5"); //or "SHA-1" md.update(input.getBytes()); BigInteger hash = new BigInteger(1, md.digest()); result = hash.toString(16); while (result.length() < 32) {//40 for SHA-1 result = "0" + result; } } return result; } /** * For test by Jason */ public static void main(String[] args) { try { System.out.println(getMd5String16("Jason")); //829018f9dbd65fb8 } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } } }
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