源代码下载地址： http://www.zuidaima.com/share/1550463378410496.htm

Java 字符串转 16 进制工具类 Hex.java 实现 16进制 0xfecd .. 和 java 字符串之间的互转换！ 如果做开发，通常用户登陆密码都会 mad5(salt + pwd) 然后再将 md 之后的数据 hex 一下。 这个工具类，就是实现此效果的。

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package com.zuidaima.haohui.common.utils;/*** <pre>* 16进制值与String/Byte之间的转换 * @author JerryLi * @email lijian@dzs.mobi * @data 2011-10-16 * http://blog.csdn.net/hzbigdog/article/details/6877712* * http://www.blogjava.net/lijinglin/archive/2011/11/02/362567.html* </pre>* * @project baidamei* @author www.zuidaima.com* @create 2012-11-14 下午5:53:14*/
public class Hex {/*** 字符串转换成十六进制字符串* * @param String*            str 待转换的ASCII字符串* @return String 每个Byte之间空格分隔，如: [61 6C 6B]*/public static String str2HexStr(String str) {char[] chars = "0123456789ABCDEF".toCharArray();StringBuilder sb = new StringBuilder("");byte[] bs = str.getBytes();int bit;for (int i = 0; i < bs.length; i++) {bit = (bs[i] & 0x0f0) >> 4;sb.append(chars[bit]);bit = bs[i] & 0x0f;sb.append(chars[bit]);sb.append(' ');}return sb.toString().trim();}/*** 十六进制转换字符串* * @param String*            str Byte字符串(Byte之间无分隔符 如:[616C6B])* @return String 对应的字符串*/public static String hexStr2Str(String hexStr) {String str = "0123456789ABCDEF";char[] hexs = hexStr.toCharArray();byte[] bytes = new byte[hexStr.length() / 2];int n;for (int i = 0; i < bytes.length; i++) {n = str.indexOf(hexs[2 * i]) * 16;n += str.indexOf(hexs[2 * i + 1]);bytes[i] = (byte) (n & 0xff);}return new String(bytes);}/*** bytes转换成十六进制字符串* * @param byte[] b byte数组* @return String 每个Byte值之间空格分隔*/public static String byte2HexStr(byte[] b) {String stmp = "";StringBuilder sb = new StringBuilder("");for (int n = 0; n < b.length; n++) {stmp = Integer.toHexString(b[n] & 0xFF);sb.append((stmp.length() == 1) ? "0" + stmp : stmp);
//          sb.append(" ");}return sb.toString().toUpperCase().trim();}/*** bytes字符串转换为Byte值* * @param String*            src Byte字符串，每个Byte之间没有分隔符* @return byte[]*/public static byte[] hexStr2Bytes(String src) {int m = 0, n = 0;int l = src.length() / 2;System.out.println(l);byte[] ret = new byte[l];for (int i = 0; i < l; i++) {m = i * 2 + 1;n = m + 1;ret[i] = Byte.decode("0x" + src.substring(i * 2, m) + src.substring(m, n));}return ret;}/*** String的字符串转换成unicode的String* * @param String*            strText 全角字符串* @return String 每个unicode之间无分隔符* @throws Exception*/public static String strToUnicode(String strText) throws Exception {char c;StringBuilder str = new StringBuilder();int intAsc;String strHex;for (int i = 0; i < strText.length(); i++) {c = strText.charAt(i);intAsc = (int) c;strHex = Integer.toHexString(intAsc);if (intAsc > 128)str.append("\\u" + strHex);else// 低位在前面补00str.append("\\u00" + strHex);}return str.toString();}/*** unicode的String转换成String的字符串* * @param String*            hex 16进制值字符串 （一个unicode为2byte）* @return String 全角字符串*/public static String unicodeToString(String hex) {int t = hex.length() / 6;StringBuilder str = new StringBuilder();for (int i = 0; i < t; i++) {String s = hex.substring(i * 6, (i + 1) * 6);// 高位需要补上00再转String s1 = s.substring(2, 4) + "00";// 低位直接转String s2 = s.substring(4);// 将16进制的string转为intint n = Integer.valueOf(s1, 16) + Integer.valueOf(s2, 16);// 将int转换为字符char[] chars = Character.toChars(n);str.append(new String(chars));}return str.toString();}public static void main(String[] args) {String hex = "ef2c71b29202f3e642f2abd8d518f367ec3fbf6a6a61beb678ae0c871ee368ac";System.out.println(Hex.hexStr2Str(hex));}
}