com.sammyun.util.MD5.java Source code

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Here is the source code for com.sammyun.util.MD5.java

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/*
 * Copyright 2012-2014 sammyun.com.cn. All rights reserved.
 * Support: http://www.sammyun.com.cn
 * License: http://www.sammyun.com.cn/license
 */
package com.sammyun.util;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SignatureException;

import org.apache.commons.codec.digest.DigestUtils;

/**
 * Utils - MD5
 * 
 * @author Sencloud Team
 * @version 3.0
 */
public class MD5 {

    public static final int OXFF = 0xff;

    public static final int OX10 = 0x10;

    /**
    * 
    */
    private MD5() {

    }

    /**
     * @param str
     * @return
     * @throws NoSuchAlgorithmException
     */
    public static String crypt(String str) throws NoSuchAlgorithmException {
        if (str == null || str.length() == 0) {
            throw new IllegalArgumentException("String to encript cannot be null or zero length");
        }

        StringBuffer hexString = new StringBuffer();

        MessageDigest md = MessageDigest.getInstance("MD5");
        md.update(str.getBytes());
        byte[] hash = md.digest();

        for (byte aHash : hash) {
            if ((OXFF & aHash) < OX10) {
                hexString.append("0").append(Integer.toHexString((OXFF & aHash)));
            } else {
                hexString.append(Integer.toHexString(OXFF & aHash));
            }
        }

        return hexString.toString();
    }

    /**
     * ??
     * 
     * @param text ???
     * @param key 
     * @param input_charset ??
     * @return ??
     */
    public static String sign(String text, String key, String input_charset) {
        text = text + key;
        return DigestUtils.md5Hex(getContentBytes(text, input_charset));
    }

    /**
     * @param content
     * @param charset
     * @return
     * @throws SignatureException
     * @throws UnsupportedEncodingException
     */
    private static byte[] getContentBytes(String content, String charset) {
        if (charset == null || "".equals(charset)) {
            return content.getBytes();
        }
        try {
            return content.getBytes(charset);
        } catch (UnsupportedEncodingException e) {
            throw new RuntimeException(
                    "MD5??,??,??:"
                            + charset);
        }
    }

    /**
     * ??
     * 
     * @param text ???
     * @param sign ??
     * @param key 
     * @param input_charset ??
     * @return ??
     */
    public static boolean verify(String text, String sign, String key, String input_charset) {
        text = text + key;
        String mysign = DigestUtils.md5Hex(getContentBytes(text, input_charset));
        if (mysign.equals(sign)) {
            return true;
        } else {
            return false;
        }
    }
}