MD5加密解密

import java.io.UnsupportedEncodingException; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; public class testee { public static void main(String[] args) { String s = new String("AAAA"); MD5Util md5 = new MD5Util(); System.out.println("原始：" + s); System.out.println("加密的：" + md5.convertMD5(s)); System.out.println("解密的：" + md5.convertMD5(md5.convertMD5(s))); } /** * 采用MD5加密解密 * @author hglp * @datetime 2015-11-03 */ public static class MD5Util { /*** * MD5加码 生成32位md5码 */ public String string2MD5(String inStr){ MessageDigest md5 = null; try{ md5 = MessageDigest.getInstance("MD5"); }catch (Exception e){ System.out.println(e.toString()); e.printStackTrace(); return ""; } char[] charArray = inStr.toCharArray(); byte[] byteArray = new byte[charArray.length]; for (int i = 0; i < charArray.length; i++) byteArray[i] = (byte) charArray[i]; byte[] md5Bytes = md5.digest(byteArray); StringBuffer hexValue = new StringBuffer(); for (int i = 0; i < md5Bytes.length; i++){ int val = ((int) md5Bytes[i]) & 0xff; if (val < 16) hexValue.append("0"); hexValue.append(Integer.toHexString(val)); } return hexValue.toString(); } /** * 加密解密算法 执行一次加密，两次解密 */ public String convertMD5(String inStr){ char[] a = inStr.toCharArray(); for (int i = 0; i < a.length; i++){ a[i] = (char) (a[i] ^ 't'); } String s = new String(a); return s; } } }