Md5加密算法

在開發中遇到的  實現Md5加密算法   傳入你想加密的數據調用該工具進行md5加密

代碼如下：

package pro_util;

import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * Created by 小林哥 on 2016/10/13.
 * md5加密工具
 */
public class Md5 {
    /**
     * Used building output as Hex
     */
    private static final char[] DIGITS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E',
            'F' };

    /**
     * 對字符串進行MD5加密
     *
     * @param text
     *
     *
     * @return 密文
     */
    public static String md5(String text, String charset) {
        MessageDigest msgDigest = null;

        try {
            msgDigest = MessageDigest.getInstance("MD5");
        } catch (NoSuchAlgorithmException e) {
            throw new IllegalStateException("System doesn't support MD5 algorithm.");
        }

        try {
            msgDigest.update(text.getBytes(charset));

        } catch (UnsupportedEncodingException e) {

            throw new IllegalStateException("System doesn't support your  EncodingException.");

        }

        byte[] bytes = msgDigest.digest();

//    String md5Str = new String(encodeHex(bytes));

        BigInteger bi = new BigInteger(1,bytes);
        return bi.toString(16);
    }

    public static char[] encodeHex(byte[] data) {

        int l = data.length;

        char[] out = new char[l << 1];

        // two characters form the hex value.
        for (int i = 0, j = 0; i < l; i++) {
            out[j++] = DIGITS[(0xF0 & data[i]) >>> 4];
            out[j++] = DIGITS[0x0F & data[i]];
        }

        return out;
    }

    public static void main(String[] args) {
        // System.out.println(md5(md5("123456","utf-8"),"utf-8"));
    }
}