微信支付--工具类--创建签名

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Formatter;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.SortedMap;

/*
'============================================================================
'api说明：
'createSHA1Sign创建签名SHA1
'getSha1()Sha1签名
'============================================================================
'*/
public class Sha1Util {
// 创建签名SHA1
public static String createSHA1Sign(SortedMap<String, String> signParams) {
StringBuffer sb = new StringBuffer();
Set es = signParams.entrySet();
Iterator it = es.iterator();
while (it.hasNext()) {
Map.Entry entry = (Map.Entry) it.next();
String k = (String) entry.getKey();
String v = (String) entry.getValue();
sb.append(k + "=" + v + "&");
// 要采用URLENCODER的原始值！
}
String params = sb.substring(0, sb.lastIndexOf("&"));
System.out.println("sha1 sb:" + params);

String sign = null;
try {
MessageDigest crypt = MessageDigest.getInstance("SHA-1");
crypt.reset();
crypt.update(params.getBytes("UTF-8"));
sign = byteToHex(crypt.digest());
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return sign;
}

private static String byteToHex(final byte[] hash) {
Formatter formatter = new Formatter();
for (byte b : hash) {
formatter.format("%02x", b);
}
String result = formatter.toString();
formatter.close();
return result;
}
}