import com.alibaba.fastjson2.JSONObject; import com.alibaba.fastjson2.JSONWriter; import lombok.extern.slf4j.Slf4j; import org.apache.commons.lang3.StringUtils; import java.nio.charset.StandardCharsets; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.util.Iterator; import java.util.Objects; import java.util.TreeMap; /** * MD5工具类 */ @Slf4j public class MD5Util { /** * 生成签名串 * * @param params 升序的参数 * @param slat 加盐：应用系统的apiKey，从控制台应用系统中获取 * @return 16进制签名串 */ public static String md5Sign(String params, String slat) { return digestToHex(params + slat); } /** * 验签 * * @param params 升序的参数 * @param sign 签名串 * @param slat 加盐：应用系统的apiKey，从控制台应用系统中获取 * @return true 表示验签通过 */ public static boolean checkSign(String params, String sign, String slat) { try { String signData = digestToHex(params + slat); log.info("生成的签名：{}", signData); return StringUtils.equals(signData, sign); } catch (Exception e) { log.error("验签异常:", e); return false; } } /** * json参数排序
*

* post请求为json传参时，调用该方法，按json中的key升序排列 *

* @param obj json参数 * @return key升序的json字符串 */ public static String sortJsonToStr(Object obj) { if (Objects.isNull(obj) || "".equals(obj)) { return ""; } if (obj instanceof Integer || obj instanceof Short || obj instanceof Long || obj instanceof Float || obj instanceof Double || obj instanceof Boolean || obj instanceof Character || obj instanceof Byte) { return String.valueOf(obj); } if (obj instanceof String) { return JSONObject.toJSONString(JSONObject.parseObject(String.valueOf(obj)), JSONWriter.Feature.MapSortField); } try { return JSONObject.toJSONString(obj, JSONWriter.Feature.MapSortField); } catch (Exception e) { return String.valueOf(obj); } } /** * url参数排序 *
* 该方法适用范围： *

get请求：url参数传参
post请求：form-data传参

* 比如: a=1&c=3&b=2 排序后 a=1&b=2&c=3 *

* * @param paraMap TreeMap类型，将参数都放入其中 * @return 按顺序拼接好的参数串 */ public static String getUrlParamsSign(TreeMap paraMap, String slat) { if (Objects.isNull(paraMap) || paraMap.isEmpty()) { return md5Sign("", slat); } Iterator it = paraMap.keySet().iterator(); StringBuilder paramStr = new StringBuilder(); while (it.hasNext()) { String key = it.next(); Object o = paraMap.get(key); if (Objects.isNull(o)) { paramStr.append("&").append(key).append("="); } else { paramStr.append("&").append(key).append("=").append(o); } } String urlParams = paramStr.substring(1); return md5Sign(urlParams, slat); } private static String digestToHex(String s) { try { MessageDigest digest = MessageDigest.getInstance("MD5"); byte[] b = digest.digest(s.getBytes(StandardCharsets.UTF_8)); return toHexString(b); } catch (NoSuchAlgorithmException e) { log.info("MD5异常,", e); return null; } } private static final char[] HEX_CHARS = new char[]{'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'}; private static String toHexString(byte[] b) { return b == null ? null : toHexString(b, 0, b.length); } private static String toHexString(byte[] b, int offset, int length) { if (b == null) { return null; } else { int end = offset + length; StringBuilder sb = new StringBuilder(length * 2); for (int i = offset; i < end; ++i) { int c = b[i] >> 4 & 15; sb.append(HEX_CHARS[c]); c = b[i] & 15; sb.append(HEX_CHARS[c]); } return sb.toString(); } } public static void main(String[] args) { // 签名的盐值，控制台应用系统中的apiKey String apiKey = "123456"; // url传参方式签名比如a=1&b=2&c=3 TreeMap paramMap = new TreeMap<>(); paramMap.put("a", 1); paramMap.put("b", 2); paramMap.put("c", 3); String urlParamsSign = getUrlParamsSign(paramMap, apiKey); System.out.println("url参数签名(getUrlParamsSign方法): " + urlParamsSign); String urlParamsSign2 = md5Sign("a=1&b=2&c=3", apiKey); System.out.println("url参数签名(md5Sign方法): " + urlParamsSign2); // json传参方式签名 String obj = "{\"a\":\"0\",\"c\":\"\",\"d\":0,\"b\":\"0\",\"c1\":\"\",\"a1\":\"0\"}"; String sortedJsonStr = sortJsonToStr(obj); System.out.println("json字符串排序结果:" + sortedJsonStr); String jsonStrSign = md5Sign(sortedJsonStr, apiKey); System.out.println("json字符串签名结果:" + jsonStrSign); JSONObject jsonObject = JSONObject.parseObject(obj); String sortedJsonStr2 = sortJsonToStr(jsonObject); System.out.println("json对象排序结果:" + sortedJsonStr2); String jsonSign = md5Sign(sortedJsonStr2, apiKey); System.out.println("json对象签名结果:" + jsonSign); } }

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