md5签名加密（用于java 后台调用短信平台接口实现发短信）

MD5Util 方法

package com.funcanteen.business.action.pay.util;

import java.security.MessageDigest;

public class MD5Util {

    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();
    }

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

    public static String MD5Encode(String origin, String charsetname) {
        String resultString = null;
        try {
            resultString = new String(origin);
            MessageDigest md = MessageDigest.getInstance("MD5");
            if (charsetname == null || "".equals(charsetname))
                resultString = byteArrayToHexString(md.digest(resultString
                        .getBytes()));
            else
                resultString = byteArrayToHexString(md.digest(resultString
                        .getBytes(charsetname)));
        } catch (Exception exception) {
        }
        return resultString;
    }
    
    private static final String hexDigits[] = { "0", "1", "2", "3", "4", "5",
        "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };
}

2：签名封装方法

   //设置签名
    public String getSignature(Map<String, String> map){
        StringBuffer sb = new StringBuffer();
        for(Map.Entry<String, String> me :map.entrySet()){
            sb.append(me.getKey()).append("=").append(me.getValue()).append("&");
        }
        sb.append("key=").append("xxxxxxxxxxxxxxxxxxxx");
        return MD5Util.MD5Encode(sb.toString(), null);
    }

3:调用签名方法

                //要发送给用户的模板信息
                TreeMap<String, String> josnMap = new TreeMap<String,String>();
                josnMap.put("name", stallApply.getAccountName());
                String jsonData = JSON.toJSONString(josnMap);
                //封装组装签名
                Map<String, String> map = new TreeMap<String,String>();
                String timestamp = System.currentTimeMillis()/1000+"";
                map.put("json", jsonData);
                map.put("mobile", stallApply.getMobile());
                map.put("templateCode", "SMS_74665033");
                map.put("timestamp",timestamp);
                String signature = getSignature(map).toUpperCase();//字母转成大写