MD5加密和验证Java程序，md5加密java,import java.

MD5加密和验证Java程序，md5加密java,import java.

import java.security.MessageDigest;/** * 对密码进行加密和验证的程序 */public class Password {    /** 十六进制下数字到字符的映射数组 */    private final static String[] hexDigits = { "0", "1", "2", "3", "4", "5",            "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };    /**     * 把inputString加密。     *      * @param inputString     *            待加密的字符串     * @return     */    public static String createPassword(String inputString) {        return encodeByMD5(inputString);    }    /**     * 验证输入的密码是否正确     *      * @param password     *            真正的密码（加密后的真密码）     * @param inputString     *            输入的字符串     * @return     */    public static boolean authenticatePassword(String password,            String inputString) {        if (password.equals(encodeByMD5(inputString))) {            return true;        } else {            return false;        }    }    /**     * 对字符串进行MD5编码     *      * @param originString     * @return     */    private static String encodeByMD5(String originString) {        if (originString != null) {            try {                MessageDigest md = MessageDigest.getInstance("MD5");                byte[] results = md.digest(originString.getBytes());                String resultString = byteArrayToHexString(results);                return resultString.toUpperCase();            } catch (Exception ex) {                ex.printStackTrace();            }        }        return null;    }    /**     * 转换字节数组为16进制字串     *      * @param b     *            字节数组     * @return 十六进制字串     */    private static String byteArrayToHexString(byte[] b) {        StringBuffer resultSb = new StringBuffer();        for (int i = 0; i < b.length; i++) {            resultSb.append(byteToHexString(b[i]));        }        return resultSb.toString();    }    /**     * 将一个字节转化成16进制形式的字符串     *      * @param b     * @return     */    private static String byteToHexString(byte b) {        int n = b;        if (n < 0)            n = 256 + n;        int d1 = n / 16;        int d2 = n % 16;        return hexDigits[d1] + hexDigits[d2];    }    public static void main(String[] args) {        String password = Password.createPassword("888888");        System.out.println("对888888用MD5摘要后的字符串：" + password);        String inputString = "8888";        System.out.println("8888与密码匹配？"                + Password.authenticatePassword(password, inputString));        inputString = "888888";        System.out.println("888888与密码匹配？"                + Password.authenticatePassword(password, inputString));    }}