com.meizu.maegis.captcha.sdk.utils.MD5Util Maven / Gradle / Ivy

Go to download
/**
 * Copyright (C) meizu Inc, 2009
 */
package com.meizu.maegis.captcha.sdk.utils;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5Util {
    private final static String[] hexDigits = {"0", "1", "2", "3", "4", "5","6", "7", "8", "9", "a", "b", "c", "d", "e", "f"};

    private static ThreadLocal MD5 = new ThreadLocal() {
        @Override
        protected MessageDigest initialValue() {
            try {
                return MessageDigest.getInstance("MD5");
            } catch (NoSuchAlgorithmException e) {
                throw new IllegalStateException("no md5 algorythm found");
            }
        }
    };


    public static String byteArrayToHexString(byte[] b) {
        StringBuffer resultSb = new StringBuffer();
        for (int i = 0; i < b.length; i++) {
            resultSb.append(byteToHexString(b[i], true));
        }
        return resultSb.toString();
    }

    public static String byteArrayToHexStringLittleEnding(byte[] b) {
        StringBuffer resultSb = new StringBuffer();
        for (int i = 0; i < b.length; i++) {
            resultSb.append(byteToHexString(b[i], false));
        }
        return resultSb.toString();
    }

    private static String byteToHexString(byte b, boolean bigEnding) {
        int n = b;
        if (n < 0)
            n = 256 + n;
        int d1 = n / 16;
        int d2 = n % 16;
        return (bigEnding) ? (hexDigits[d1] + hexDigits[d2]) : (hexDigits[d2] + hexDigits[d1]);
    }

    public static String MD5Encode(String origin) {
        return MD5Encode(origin, null);
    }


    public static byte[] hexStringToByteArray(String s) {
        if (s.length() % 2 != 0) {
            throw new RuntimeException("Error Hex String length");
        }
        byte[] result = new byte[s.length() / 2];
        for (int i = 0; i < s.length(); ) {
            int bytepos = i / 2;
            char c = s.charAt(i++);
            char c2 = s.charAt(i++);
            result[bytepos] = Integer.decode("0x" + c + c2).byteValue();
        }
        return result;
    }


    public static String MD5Encode(String origin, String encoding) {
        String resultString = null;

        try {
            resultString = new String(origin);
            MessageDigest md = MD5.get();
            if (encoding == null) {
                resultString = byteArrayToHexString(md.digest(resultString
                        .getBytes()));
            } else {
                resultString = byteArrayToHexString(md.digest(resultString
                        .getBytes(encoding)));
            }

        } catch (Exception e) {
            throw new RuntimeException(e);
        }

        return resultString;
    }

    public static MessageDigest getMd5Digest() {
        return MD5.get();
    }

    public static byte[] MD5Encode(byte origin[]) {
        try {
            MessageDigest md = MD5.get();
            return md.digest(origin);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}