微信公众号开发《五》基于Java实现微信支付(公众号支付)简单教程

时间:2022-08-31 22:41:52

最近公司需求,需要在微信公众号内完成支付,找到官方文档,文档还可以,讲的也挺详细,不过有一个地方很坑爹,就是微信内H5调起支付需要一个签名,而他给出的参考签名方式跟统一下单签名一致,害的我以为,他这个签名就是统一下单那个签名,后面找了很久看了好多博客才明白这个签名是怎么生成的(JS-SDK中微信支付有说明)。弄了半天,汗颜。下面进入正题。

微信支付分为很多种,有刷卡支付,公众号支付,扫码支付,APP支付,H5支付,小程序支付,本教程只讲解公众号支付。主要分三大块来讲解。

1.公众号支付介绍

微信支付只面向已认证客户,需要申请,申请成功后有个商家号,还要一个API密匙即key(微信商户平台(pay.weixin.qq.com)-->账户中心-->账户设置-->API安全-->密钥设置)。而公众号支付是用户在微信中打开商户的H5页面,商户在H5页面通过调用微信支付提供的JSAPI接口调起微信支付模块完成支付。应用场景有:
◆ 用户在微信公众账号内进入商家公众号,打开某个主页面,完成支付
◆ 用户的好友在朋友圈、聊天窗口等分享商家页面连接,用户点击链接打开商家页面,完成支付
◆ 将商户页面转换成二维码,用户扫描二维码后在微信浏览器中打开页面后完成支付

2.开发流程

在这里贴出官方文档地址https://pay.weixin.qq.com/wiki/doc/api/jsapi.php?chapter=7_1。有兴趣的可以研究研究,贴出最主要的业务流程图:
微信公众号开发《五》基于Java实现微信支付(公众号支付)简单教程
啥,看不下去,那简单来说,你要掌握三点:

1.在商家后台设置支付目录, 设置路径:商户平台-->产品中心-->开发配置。填写你项目所在域名

2.在公众号后台 设置授权域名,因为在统一下单接口中要求必传用户openid,而获取openid则需要您在公众平台设置获取openid的域名,只有被设置过的域名才是一个有效的获取openid的域名,否则将获取失败。

3.调通统一下单 支付结果通知接口(详细看demo)

tip:如果不知道如何获取openid,可以看本人另外一篇博客微信公众号开发《一》OAuth2.0网页授权认证获取用户的详细信息,实现自动登陆

3.demo展示

demo使用了包:xstream-1.3.1.jar,jdom.jar,用于把数据封装成xml格式与xml解析。首先我们把请求参数封装成类
/**
* 统一下单请求参数
* @author lhao
*
*/
public class UnifiedOrderRequest {
//变量名 字段名 必填 类型 示例值 描述
private String appid;// 公众账号ID 是 String(32) wxd678efh567hg6787 微信支付分配的公众账号ID(企业号corpid即为此appId)
private String mch_id;//商户号 必填 String(32) 1230000109 微信支付分配的商户号
private String device_info; //设备号 否 String(32) 013467007045764 自定义参数,可以为终端设备号(门店号或收银设备ID),PC网页或公众号内支付可以传"WEB"
private String nonce_str;//随机字符串 是 String(32) 5K8264ILTKCH16CQ2502SI8ZNMTM67VS 随机字符串,长度要求在32位以内。推荐随机数生成算法
private String sign;//签名 是 String(32) C380BEC2BFD727A4B6845133519F3AD6 通过签名算法计算得出的签名值,详见签名生成算法
private String sign_type;//签名类型 sign_type 否 String(32) HMAC-SHA256 签名类型,默认为MD5,支持HMAC-SHA256和MD5。
private String body;//商品描述 body 是 String(128) 腾讯充值中心-QQ会员充值 商品简单描述,该字段请按照规范传递,具体请见参数规定
private String detail;//商品详情 detail 否 String(6000) 单品优惠字段(暂未上线)
private String attach;//附加数据 attach 否 String(127) 深圳分店 附加数据,在查询API和支付通知中原样返回,可作为自定义参数使用。
private String out_trade_no;//商户订单号 out_trade_no 是 String(32) 20150806125346 商户系统内部订单号,要求32个字符内,只能是数字、大小写字母_-|*@ ,且在同一个商户号下唯一。详见商户订单号
private String fee_type;//标价币种 fee_type 否 String(16) CNY 符合ISO 4217标准的三位字母代码,默认人民币:CNY,详细列表请参见货币类型
private String total_fee;//标价金额 total_fee 是 Int 88 订单总金额,单位为分,详见支付金额
private String spbill_create_ip;//终端IP spbill_create_ip 是 String(16) 123.12.12.123 APP和网页支付提交用户端ip,Native支付填调用微信支付API的机器IP。
private String time_start;//交易起始时间 time_start 否 String(14) 20091225091010 订单生成时间,格式为yyyyMMddHHmmss,如2009年12月25日9点10分10秒表示为20091225091010。其他详见时间规则
private String time_expire;//交易结束时间 time_expire 否 String(14) 20091227091010 订单失效时间,格式为yyyyMMddHHmmss,如2009年12月27日9点10分10秒表示为20091227091010。其他详见时间规则 注意:最短失效时间间隔必须大于5分钟
private String goods_tag;//订单优惠标记 goods_tag 否 String(32) WXG 订单优惠标记,使用代金券或立减优惠功能时需要的参数,说明详见代金券或立减优惠
private String notify_url;//通知地址 notify_url 是 String(256) http://www.weixin.qq.com/wxpay/pay.php 异步接收微信支付结果通知的回调地址,通知url必须为外网可访问的url,不能携带参数。
private String trade_type;//交易类型 trade_type 是 String(16) JSAPI 取值如下:JSAPI,NATIVE,APP等,说明详见参数规定
private String product_id;//商品ID product_id 否 String(32) 12235413214070356458058 trade_type=NATIVE时(即扫码支付),此参数必传。此参数为二维码中包含的商品ID,商户自行定义。
private String limit_pay;//指定支付方式 limit_pay 否 String(32) no_credit 上传此参数no_credit--可限制用户不能使用信用卡支付
private String openid;//用户标识 openid 否 String(128) oUpF8uMuAJO_M2pxb1Q9zNjWeS6o trade_type=JSAPI时(即公众号支付),此参数必传,此参数为微信用户在商户对应appid下的唯一标识。openid如何获取,可参考【获取openid】。企业号请使用【企业号OAuth2.0接口】获取企业号内成员userid,再调用【企业号userid转openid接口】进行转换

//省略get,set方法
}
/** * 统一下单返回参数 * @author lhao * */public class UnifiedOrderRespose {    private String return_code;             //返回状态码    private String return_msg;              //返回信息    private String appid;                   //公众账号ID    private String mch_id;                  //商户号    private String device_info;             //设备号    private String nonce_str;               //随机字符串    private String sign;                    //签名    private String result_code;             //业务结果    private String err_code;                //错误代码    private String err_code_des;            //错误代码描述    private String trade_type;              //交易类型    private String prepay_id;               //预支付交易会话标识    private String code_url;                //二维码链接        //省略get/set方法}
/**
* 常量
*/
public class WXPayConstants {

public enum SignType {
MD5, HMACSHA256
}
public static final String FAIL = "FAIL";
public static final String SUCCESS = "SUCCESS";
public static final String HMACSHA256 = "HMAC-SHA256";
public static final String MD5 = "MD5";
public static final String FIELD_SIGN = "sign";
public static final String FIELD_SIGN_TYPE = "sign_type";

}
MD5加密工具类,封装参数、请求工具类
import java.security.MessageDigest;
/**
* MD5工具类
* @author lh
*/
public class MD5Util {
public final static String MD5(String s) {
char hexDigits[]={'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};

try {
byte[] btInput = s.getBytes();
// 鑾峰緱MD5鎽樿绠楁硶鐨�MessageDigest 瀵硅�?
MessageDigest mdInst = MessageDigest.getInstance("MD5");
// 浣跨敤鎸囧畾鐨勫瓧鑺傛洿鏂版憳瑕�?
mdInst.update(btInput);
// 鑾峰緱�?�嗘�?
byte[] md = mdInst.digest();
// 鎶婂瘑鏂囪浆鎹㈡垚鍗佸叚杩涘埗鐨勫瓧绗︿覆褰㈠紡
int j = md.length;
char str[] = new char[j * 2];
int k = 0;
for (int i = 0; i < j; i++) {
byte byte0 = md[i];
str[k++] = hexDigits[byte0 >>> 4 & 0xf];
str[k++] = hexDigits[byte0 & 0xf];
}
String md5Str = new String(str);
return md5Str;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}
import java.io.BufferedOutputStream;import java.io.BufferedReader;import java.io.ByteArrayInputStream;import java.io.InputStream;import java.io.InputStreamReader;import java.io.StringWriter;import java.io.Writer;import java.net.HttpURLConnection;import java.net.URL;import java.util.*;import java.security.MessageDigest;import org.w3c.dom.Node;import org.w3c.dom.NodeList;import com.thoughtworks.xstream.XStream;import com.thoughtworks.xstream.core.util.QuickWriter;import com.thoughtworks.xstream.io.HierarchicalStreamWriter;import com.thoughtworks.xstream.io.xml.PrettyPrintWriter;import com.thoughtworks.xstream.io.xml.XppDriver;import wp.WXPayConstants.SignType;import javax.crypto.Mac;import javax.crypto.spec.SecretKeySpec;import javax.xml.parsers.DocumentBuilder;import javax.xml.parsers.DocumentBuilderFactory;import javax.xml.transform.OutputKeys;import javax.xml.transform.Transformer;import javax.xml.transform.TransformerFactory;import javax.xml.transform.dom.DOMSource;import javax.xml.transform.stream.StreamResult;import org.apache.commons.lang.RandomStringUtils;import org.jdom.Document;import org.jdom.Element;import org.jdom.input.SAXBuilder;import org.slf4j.Logger;import org.slf4j.LoggerFactory;/** * 支付工具类 * @author lh */public class WXPayUtil {	private static Logger log = LoggerFactory.getLogger(WXPayUtil.class);		/**	 * 生成订单对象信息	 * @param orderId 订单号	 * @param appId 微信appId	 * @param mch_id 微信分配的商户ID	 * @param body  支付介绍主体	 * @param price 支付价格(放大100倍)	 * @param spbill_create_ip 终端IP	 * @param notify_url  异步直接结果通知接口地址	 * @param noncestr 	 * @return	 */	public static Map<String,Object> createOrderInfo(Map<String, String> requestMap) {  	    //生成订单对象  	    UnifiedOrderRequest unifiedOrderRequest = new UnifiedOrderRequest();  	    unifiedOrderRequest.setAppid(requestMap.get("appId"));//公众账号ID  	    unifiedOrderRequest.setBody(requestMap.get("body"));//商品描述  	    unifiedOrderRequest.setMch_id(requestMap.get("mch_id"));//商户号  	    unifiedOrderRequest.setNonce_str(requestMap.get("noncestr"));//随机字符串    	    unifiedOrderRequest.setNotify_url(requestMap.get("notify_url"));//通知地址  	    unifiedOrderRequest.setOpenid(requestMap.get("userWeixinOpenId"));	    unifiedOrderRequest.setDetail(requestMap.get("detail"));//详情	    unifiedOrderRequest.setOut_trade_no(requestMap.get("out_trade_no"));//商户订单号  	    unifiedOrderRequest.setSpbill_create_ip(requestMap.get("spbill_create_ip"));//终端IP  	    unifiedOrderRequest.setTotal_fee(requestMap.get("payMoney"));  //金额需要扩大100倍:1代表支付时是0.01  	    unifiedOrderRequest.setTrade_type("JSAPI");//JSAPI--公众号支付、NATIVE--原生扫码支付、APP--app支付	    SortedMap<String, String> packageParams = new TreeMap<String, String>();  	    packageParams.put("appid", unifiedOrderRequest.getAppid());  	    packageParams.put("body", unifiedOrderRequest.getBody());  	    packageParams.put("mch_id", unifiedOrderRequest.getMch_id());  	    packageParams.put("nonce_str", unifiedOrderRequest.getNonce_str());  	    packageParams.put("notify_url", unifiedOrderRequest.getNotify_url());	    packageParams.put("openid", unifiedOrderRequest.getOpenid());	    packageParams.put("detail", unifiedOrderRequest.getDetail());	    packageParams.put("out_trade_no", unifiedOrderRequest.getOut_trade_no());  	    packageParams.put("spbill_create_ip", unifiedOrderRequest.getSpbill_create_ip());  	    packageParams.put("total_fee", unifiedOrderRequest.getTotal_fee());  	    packageParams.put("trade_type", unifiedOrderRequest.getTrade_type());  	    try {			unifiedOrderRequest.setSign(generateSignature(packageParams,"你的密匙"));//签名		} catch (Exception e) {			e.printStackTrace();		}	    //将订单对象转为xml格式  	    xstream.alias("xml", UnifiedOrderRequest.class);//根元素名需要是xml  	    System.out.println("封装好的统一下单请求数据:"+xstream.toXML(unifiedOrderRequest).replace("__", "_"));	    Map<String,Object> responseMap = new HashMap<String,Object>();	    responseMap.put("orderInfo_toString", xstream.toXML(unifiedOrderRequest).replace("__", "_"));	    responseMap.put("unifiedOrderRequest",unifiedOrderRequest);	    return responseMap;  	} 		/** 	 * 生成签名 	 * @param appid_value 	 * @param mch_id_value 	 * @param productId 	 * @param nonce_str_value 	 * @param trade_type  	 * @param notify_url  	 * @param spbill_create_ip  	 * @param total_fee  	 * @param out_trade_no  	 * @return 	 */  	private static String createSign(UnifiedOrderRequest unifiedOrderRequest) {  	    //根据规则创建可排序的map集合  	    SortedMap<String, String> packageParams = new TreeMap<String, String>();  	    packageParams.put("appid", unifiedOrderRequest.getAppid());  	    packageParams.put("body", unifiedOrderRequest.getBody());  	    packageParams.put("mch_id", unifiedOrderRequest.getMch_id());  	    packageParams.put("nonce_str", unifiedOrderRequest.getNonce_str());  	    packageParams.put("notify_url", unifiedOrderRequest.getNotify_url());  	    packageParams.put("out_trade_no", unifiedOrderRequest.getOut_trade_no());  	    packageParams.put("spbill_create_ip", unifiedOrderRequest.getSpbill_create_ip());  	    packageParams.put("trade_type", unifiedOrderRequest.getTrade_type());  	    packageParams.put("total_fee", unifiedOrderRequest.getTotal_fee());  	    StringBuffer sb = new StringBuffer();  	    Set es = packageParams.entrySet();//字典序  	    Iterator it = es.iterator();  	    while (it.hasNext()) {  	        Map.Entry entry = (Map.Entry) it.next();  	        String k = (String) entry.getKey();  	        String v = (String) entry.getValue();  	        //为空不参与签名、参数名区分大小写  	        if (null != v && !"".equals(v) && !"sign".equals(k)  && !"key".equals(k)) {  	            sb.append(k + "=" + v + "&");  	        }  	    }  	    //第二步拼接key,key设置路径:微信商户平台(pay.weixin.qq.com)-->账户设置-->API安全-->密钥设置  	    sb.append("key="+"你的密匙");  	    String sign = MD5Util.MD5(sb.toString()).toUpperCase();//MD5加密  	    log.error("方式一生成的签名="+sign);	    return sign;  	}		private static XStream xstream = new XStream(new XppDriver() {          public HierarchicalStreamWriter createWriter(Writer out) {              return new PrettyPrintWriter(out) {                  // 对所有xml节点的转换都增加CDATA标记                  boolean cdata = true;                  String NodeName = "";                @SuppressWarnings("unchecked")                  public void startNode(String name, Class clazz) {                  	NodeName = name;                    super.startNode(name, clazz);                  }                  protected void writeText(QuickWriter writer, String text) {                      if (cdata) {                      	if(!NodeName.equals("detail")){                    		writer.write(text);                     	}else{                    		writer.write("<![CDATA[");                              writer.write(text);                              writer.write("]]>");                     	}                    } else {                          writer.write(text);                      }                  }              };          }      }); 		//xml解析        public static SortedMap<String, String> doXMLParseWithSorted(String strxml) throws Exception {              strxml = strxml.replaceFirst("encoding=\".*\"", "encoding=\"UTF-8\"");              if(null == strxml || "".equals(strxml)) {                  return null;              }              SortedMap<String,String> m = new TreeMap<String,String>();               InputStream in = new ByteArrayInputStream(strxml.getBytes("UTF-8"));              SAXBuilder builder = new SAXBuilder();              Document doc = builder.build(in);              Element root = doc.getRootElement();              List list = root.getChildren();              Iterator it = list.iterator();              while(it.hasNext()) {                  Element e = (Element) it.next();                  String k = e.getName();                  String v = "";                  List children = e.getChildren();                  if(children.isEmpty()) {                      v = e.getTextNormalize();                  } else {                      v = getChildrenText(children);                  }                  m.put(k, v);              }              //关闭流              in.close();               return m;        }           public static String getChildrenText(List children) {            StringBuffer sb = new StringBuffer();            if(!children.isEmpty()) {                Iterator it = children.iterator();                while(it.hasNext()) {                    Element e = (Element) it.next();                    String name = e.getName();                    String value = e.getTextNormalize();                    List list = e.getChildren();                    sb.append("<" + name + ">");                    if(!list.isEmpty()) {                        sb.append(getChildrenText(list));                    }                    sb.append(value);                    sb.append("</" + name + ">");                }            }             return sb.toString();    	} 	/** 	 * 调统一下单API 	 * @param orderInfo 	 * @return 	 */  	public static UnifiedOrderRespose httpOrder(String orderInfo) {  	    String url = "https://api.mch.weixin.qq.com/pay/unifiedorder";  	    try {  	        HttpURLConnection conn = (HttpURLConnection) new URL(url).openConnection();  	        //加入数据    			conn.setRequestMethod("POST");    			conn.setDoOutput(true);    			BufferedOutputStream buffOutStr = new BufferedOutputStream(conn.getOutputStream());    			buffOutStr.write(orderInfo.getBytes("UTF-8"));  			buffOutStr.flush();    			buffOutStr.close();    			//获取输入流    			BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream(), "UTF-8"));    			String line = null;    			StringBuffer sb = new StringBuffer();    			while((line = reader.readLine())!= null){    				sb.append(line);    			}    			//将请求返回的内容通过xStream转换为UnifiedOrderRespose对象  			xstream.alias("xml", UnifiedOrderRespose.class);  			UnifiedOrderRespose unifiedOrderRespose = (UnifiedOrderRespose)xstream.fromXML(sb.toString());  			return unifiedOrderRespose;	    } catch (Exception e) {  	        e.printStackTrace();  	    }  	    return null;  	}      /**     * XML格式字符串转换为Map     *     * @param strXML XML字符串     * @return XML数据转换后的Map     * @throws Exception     */    public static Map<String, String> xmlToMap(String strXML) throws Exception {        try {            Map<String, String> data = new HashMap<String, String>();            DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();            DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();            InputStream stream = new ByteArrayInputStream(strXML.getBytes("UTF-8"));            org.w3c.dom.Document doc = documentBuilder.parse(stream);            doc.getDocumentElement().normalize();            NodeList nodeList = doc.getDocumentElement().getChildNodes();            for (int idx = 0; idx < nodeList.getLength(); ++idx) {                Node node = nodeList.item(idx);                if (node.getNodeType() == Node.ELEMENT_NODE) {                    org.w3c.dom.Element element = (org.w3c.dom.Element) node;                    data.put(element.getNodeName(), element.getTextContent());                }            }            try {                stream.close();            } catch (Exception ex) {                // do nothing            }            return data;        } catch (Exception ex) {            WXPayUtil.getLogger().warn("Invalid XML, can not convert to map. Error message: {}. XML content: {}", ex.getMessage(), strXML);            throw ex;        }    }    /**     * 将Map转换为XML格式的字符串     *     * @param data Map类型数据     * @return XML格式的字符串     * @throws Exception     */    public static String mapToXml(Map<String, String> data) throws Exception {        DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();        DocumentBuilder documentBuilder= documentBuilderFactory.newDocumentBuilder();        org.w3c.dom.Document document = documentBuilder.newDocument();        org.w3c.dom.Element root = document.createElement("xml");        document.appendChild(root);        for (String key: data.keySet()) {            String value = data.get(key);            if (value == null) {                value = "";            }            value = value.trim();            org.w3c.dom.Element filed = document.createElement(key);            filed.appendChild(document.createTextNode(value));            root.appendChild(filed);        }        TransformerFactory tf = TransformerFactory.newInstance();        Transformer transformer = tf.newTransformer();        DOMSource source = new DOMSource(document);        transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8");        transformer.setOutputProperty(OutputKeys.INDENT, "yes");        StringWriter writer = new StringWriter();        StreamResult result = new StreamResult(writer);        transformer.transform(source, result);        String output = writer.getBuffer().toString(); //.replaceAll("\n|\r", "");        try {            writer.close();        }        catch (Exception ex) {        }        return output;    }    /**     * 生成带有 sign 的 XML 格式字符串     *     * @param data Map类型数据     * @param key API密钥     * @return 含有sign字段的XML     */    public static String generateSignedXml(final Map<String, String> data, String key) throws Exception {        return generateSignedXml(data, key, SignType.MD5);    }    /**     * 生成带有 sign 的 XML 格式字符串     *     * @param data Map类型数据     * @param key API密钥     * @param signType 签名类型     * @return 含有sign字段的XML     */    public static String generateSignedXml(final Map<String, String> data, String key, SignType signType) throws Exception {        String sign = generateSignature(data, key, signType);        data.put(WXPayConstants.FIELD_SIGN, sign);        return mapToXml(data);    }    /**     * 判断签名是否正确     *     * @param xmlStr XML格式数据     * @param key API密钥     * @return 签名是否正确     * @throws Exception     */    public static boolean isSignatureValid(String xmlStr, String key) throws Exception {        Map<String, String> data = xmlToMap(xmlStr);        if (!data.containsKey(WXPayConstants.FIELD_SIGN) ) {            return false;        }        String sign = data.get(WXPayConstants.FIELD_SIGN);        return generateSignature(data, key).equals(sign);    }    /**     * 判断签名是否正确,必须包含sign字段,否则返回false。使用MD5签名。     *     * @param data Map类型数据     * @param key API密钥     * @return 签名是否正确     * @throws Exception     */    public static boolean isSignatureValid(Map<String, String> data, String key) throws Exception {        return isSignatureValid(data, key, SignType.MD5);    }    /**     * 判断签名是否正确,必须包含sign字段,否则返回false。     *     * @param data Map类型数据     * @param key API密钥     * @param signType 签名方式     * @return 签名是否正确     * @throws Exception     */    public static boolean isSignatureValid(Map<String, String> data, String key, SignType signType) throws Exception {        if (!data.containsKey(WXPayConstants.FIELD_SIGN) ) {            return false;        }        String sign = data.get(WXPayConstants.FIELD_SIGN);        return generateSignature(data, key, signType).equals(sign);    }    /**     * 生成签名     *     * @param data 待签名数据     * @param key API密钥     * @return 签名     */    public static String generateSignature(final Map<String, String> data, String key) throws Exception {        return generateSignature(data, key, SignType.MD5);    }    /**     * 生成签名. 注意,若含有sign_type字段,必须和signType参数保持一致。     *     * @param data 待签名数据     * @param key API密钥     * @param signType 签名方式     * @return 签名     */    public static String generateSignature(final Map<String, String> data, String key, SignType signType) throws Exception {        Set<String> keySet = data.keySet();        String[] keyArray = keySet.toArray(new String[keySet.size()]);        Arrays.sort(keyArray);        StringBuilder sb = new StringBuilder();        for (String k : keyArray) {            if (k.equals(WXPayConstants.FIELD_SIGN)) {                continue;            }            if (data.get(k).trim().length() > 0) // 参数值为空,则不参与签名                sb.append(k).append("=").append(data.get(k).trim()).append("&");        }        sb.append("key=").append(key);        if (SignType.MD5.equals(signType)) {            return MD5(sb.toString()).toUpperCase();        }        else if (SignType.HMACSHA256.equals(signType)) {            return HMACSHA256(sb.toString(), key);        }        else {        	log.error("获取签名失败,失败原因:"+String.format("Invalid sign_type: %s", signType));            throw new Exception(String.format("Invalid sign_type: %s", signType));        }    }    /**     * 获取随机字符串 Nonce Str     * @return String 随机字符串     */    public static String generateNonceStr() {        return UUID.randomUUID().toString().replaceAll("-", "").substring(0, 32);    }    /**      * Map转xml数据      */      public static String GetMapToXML(Map<String,String> param){          StringBuffer sb = new StringBuffer();          sb.append("<xml>");          for (Map.Entry<String,String> entry : param.entrySet()) {           	sb.append("<"+ entry.getKey() +">");          	sb.append(entry.getValue());          	sb.append("</"+ entry.getKey() +">");          }            sb.append("</xml>");          return sb.toString();      }      /**     * 生成 MD5     * @param data 待处理数据     * @return MD5结果     */    public static String MD5(String data) throws Exception {        java.security.MessageDigest md = MessageDigest.getInstance("MD5");        byte[] array = md.digest(data.getBytes("UTF-8"));        StringBuilder sb = new StringBuilder();        for (byte item : array) {            sb.append(Integer.toHexString((item & 0xFF) | 0x100).substring(1, 3));        }        return sb.toString().toUpperCase();    }    /**     * 生成 HMACSHA256     * @param data 待处理数据     * @param key 密钥     * @return 加密结果     * @throws Exception     */    public static String HMACSHA256(String data, String key) throws Exception {        Mac sha256_HMAC = Mac.getInstance("HmacSHA256");        SecretKeySpec secret_key = new SecretKeySpec(key.getBytes("UTF-8"), "HmacSHA256");        sha256_HMAC.init(secret_key);        byte[] array = sha256_HMAC.doFinal(data.getBytes("UTF-8"));        StringBuilder sb = new StringBuilder();        for (byte item : array) {            sb.append(Integer.toHexString((item & 0xFF) | 0x100).substring(1, 3));        }        return sb.toString().toUpperCase();    }    /**     * 日志     * @return     */    public static Logger getLogger() {        Logger logger = LoggerFactory.getLogger("wxpay java sdk");        return logger;    }    /**     * 获取当前时间戳,单位秒     * @return     */    public static long getCurrentTimestamp() {        return System.currentTimeMillis()/1000;    }    /**     * 获取当前时间戳,单位毫秒     * @return     */    public static long getCurrentTimestampMs() {        return System.currentTimeMillis();    }    /**     * 生成 uuid, 即用来标识一笔单,也用做 nonce_str     * @return     */    public static String generateUUID() {        return UUID.randomUUID().toString().replaceAll("-", "").substring(0, 32);    }    /**      * 支付签名      * @param timestamp      * @param noncestr      * @param packages      * @return      * @throws UnsupportedEncodingException       */      public static String paySign(String timestamp, String noncestr,String packages,String appId){          Map<String, String> paras = new HashMap<String, String>();          paras.put("appid", appId);          paras.put("timestamp", timestamp);          paras.put("noncestr", noncestr);          paras.put("package", packages);          paras.put("signType", "MD5");  	    StringBuffer sb = new StringBuffer();  	    Set es = paras.entrySet();//字典序  	    Iterator it = es.iterator();  	    while (it.hasNext()) {  	        Map.Entry entry = (Map.Entry) it.next();  	        String k = (String) entry.getKey();  	        String v = (String) entry.getValue();  	        //为空不参与签名、参数名区分大小写  	        if (null != v && !"".equals(v) && !"sign".equals(k)  && !"key".equals(k)) {  	            sb.append(k + "=" + v + "&");  	        }  	    }  	    String sign = MD5Util.MD5(sb.toString()).toUpperCase();//MD5加密          return sign;      }  }
一些准备就绪,下面我们看看调用方法
import java.util.HashMap;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import com.photovoltaic.model.ResultEnum;
import com.photovoltaic.model.UserOrderInfo;
import com.photovoltaic.model.UserPayInfo;
import com.photovoltaic.util.publicUtil;
import com.photovoltaic.weixin.model.TemplateData;
import com.photovoltaic.weixin.model.TimedTask;
import com.photovoltaic.weixin.model.UnifiedOrderRequest;
import com.photovoltaic.weixin.model.UnifiedOrderRespose;
import com.photovoltaic.weixin.model.WxTemplate;
import com.photovoltaic.weixin.util.WXPayUtil;
import com.photovoltaic.weixin.util.WeixinUtil;

/**
* 微信支付controller
* 1.用户发起微信支付,初始化数据、调用统一下单接口。生成JSAPI页面调用的支付参数并签名(paySign,prepay_id,nonceStr,timestamp)
* 2.js如果返回Ok,提示支付成功,实际支付结果已收到通知为主。
* 3.在微信支付结果通知中,获取微信提供的最终用户支付结果信息,支付结果等信息更新用户支付记录中
* 4.根据微信支付结果通知中的微信订单号调用查询接口,如果查询是已经支付成功,则发送支付成功模板信息给客户
* @author hl
*
*/
@Controller
@RequestMapping(value = "/pay")
public class WXPayController extends WeixinBaseController{
private static Logger log = LoggerFactory.getLogger(WXPayController.class);
/**
* 获取终端IP
* @param request
* @return
*/
public static String getIpAddr(HttpServletRequest request) {
String ip = request.getHeader( " x-forwarded-for " );
if (ip == null || ip.length() == 0 || " unknown " .equalsIgnoreCase(ip)) {
ip = request.getHeader( " Proxy-Client-IP " );
}
if (ip == null || ip.length() == 0 || " unknown " .equalsIgnoreCase(ip)) {
ip = request.getHeader( " WL-Proxy-Client-IP " );
}
if (ip == null || ip.length() == 0 || " unknown " .equalsIgnoreCase(ip)) {
ip = request.getRemoteAddr();
}
return ip;
}
/**
* 支付初始化
* @param payMoney
* @return
*/
@RequestMapping("/toPayInit")
@ResponseBody
public Map<String,Object> toPay(@RequestParam(value="payMoney",required=true) String payMoney,@RequestParam(value="userWeixinOpenId",required=true) String userWeixinOpenId){
Map<String,Object> map = new HashMap<>();
String orderId = String.valueOf(WXPayUtil.generateUUID());
String noncestr = WXPayUtil.generateNonceStr();
Map<String,String> requestMap = new HashMap<String, String>();
requestMap.put("appId", "wx3fda6310becfe801");
requestMap.put("userWeixinOpenId",userWeixinOpenId);
requestMap.put("out_trade_no",orderId);
requestMap.put("mch_id", "商家号");
requestMap.put("payMoney",payMoney);
requestMap.put("spbill_create_ip", getIpAddr(request));
requestMap.put("notify_url", "支付结果回调通知路径");
requestMap.put("noncestr", noncestr);
requestMap.put("body","一元联系");
requestMap.put("detail","获取电站用户的联系方式");
Map<String,Object> requestInfo = WXPayUtil.createOrderInfo(requestMap);
String orderInfo_toString = (String) requestInfo.get("orderInfo_toString");
//判断返回码
UnifiedOrderRespose orderResponse = WXPayUtil.httpOrder(orderInfo_toString);// 调用统一下单接口
//根据微信文档return_code 和result_code都为SUCCESS的时候才会返回code_url
if(null!=orderResponse && "SUCCESS".equals(orderResponse.getReturn_code()) && "SUCCESS".equals(orderResponse.getResult_code())){
String timestamp = String.valueOf(WXPayUtil.getCurrentTimestamp());
map.put("timestamp",timestamp);
map.put("noncestr",noncestr);
UnifiedOrderRequest unifiedOrderRequest = (UnifiedOrderRequest) requestInfo.get("unifiedOrderRequest");
map.put("unifiedOrderRequest",unifiedOrderRequest);
SortedMap<String, String> packageParams = new TreeMap<String, String>();
packageParams.put("appId","你的appId");
packageParams.put("signType","MD5");
packageParams.put("nonceStr", noncestr);
packageParams.put("timeStamp", timestamp);
String packages = "prepay_id="+orderResponse.getPrepay_id();
packageParams.put("package",packages);
String sign = null;//这个梗,就是开头说的,弄了半天才弄出来的
try {
sign = WXPayUtil.generateSignature(packageParams,"你的密匙");
} catch (Exception e) {
map.put("result",-1);
e.printStackTrace();
}
if(sign!=null && !"".equals(sign)){
map.put("paySign",sign);
map.put("result",1);
}else{
map.put("result",-1);
}
map.put("prepay_id",orderResponse.getPrepay_id());
return map;
}else{ //不成功
String text = "调用微信支付出错,返回状态码:"+orderResponse.getReturn_code()+",返回信息:"+orderResponse.getReturn_msg();
if(orderResponse.getErr_code()!=null && !"".equals(orderResponse.getErr_code())){
text = text +",错误码:"+orderResponse.getErr_code()+",错误描述:"+orderResponse.getErr_code_des();
}
log.error(text);
map.put("result",-1);
return map;
}
}

/**
* 异步回调接口
* @param request
* @param response
* @throws Exception
*/
@RequestMapping(value="/paymentNotice",produces="text/html;charset=utf-8")
@ResponseBody
public String WeixinParentNotifyPage(HttpServletRequest request,HttpServletResponse response) throws Exception{
ServletInputStream instream = request.getInputStream();
StringBuffer sb = new StringBuffer();
int len = -1;
byte[] buffer = new byte[1024];
while((len = instream.read(buffer)) != -1){
sb.append(new String(buffer,0,len));
}
instream.close();
// log.error("支付通知回调信息:"+sb.toString());
// Map<String,String> map = WXPayUtil.doXMLParseWithSorted(sb.toString());//接受微信的通知参数
Map<String,String> map = WXPayUtil.xmlToMap(sb.toString());//接受微信的回调的通知参数
Map<String,String> return_data = new HashMap<String,String>();
//判断签名是否正确
if(WXPayUtil.isSignatureValid(map, "你的密匙")){
if(map.get("return_code").toString().equals("FAIL")){
return_data.put("return_code", "FAIL");
return_data.put("return_msg", map.get("return_msg"));
}else if(map.get("return_code").toString().equals("SUCCESS")){
String result_code = map.get("result_code").toString();
String out_trade_no = map.get("out_trade_no").toString();
//获得你自己的订单详情
UserPayInfo payInfo = wxPayService.getUserPayInfo(out_trade_no);
if(payInfo == null){
return_data.put("return_code", "FAIL");
return_data.put("return_msg", "订单不存在");
return WeixinUtil.GetMapToXML(return_data);
}else{
//2 已支付(不确定是否支付成功)3 支付完成 4 取消支付 5支付失败
if(result_code.equals("SUCCESS")){//支付成功
//如果订单已经支付直接返回成功
if(payInfo.getPayStatus()==3){
return_data.put("return_code", "SUCCESS");
return_data.put("return_msg", "OK");
return WXPayUtil.GetMapToXML(return_data);
}else{
String sign = map.get("sign").toString();
String total_fee = map.get("total_fee").toString();//订单金额
if(!publicUtil.subZeroAndDot3(payInfo.getTotal_fee().toString()).equals(total_fee)){//订单金额是否一致
return_data.put("return_code", "FAIL");
return_data.put("return_msg", "金额异常");
}else{
String time_end = map.get("time_end").toString();
String bank_type = map.get("bank_type").toString();
String settlement_total_fee = map.get("settlement_total_fee");
if(settlement_total_fee==null || "".equals(settlement_total_fee)){
settlement_total_fee = "0";
}
payInfo.setSign(sign);
payInfo.setResult_code(result_code);
payInfo.setPayStatus(3);
payInfo.setTime_end(time_end);
payInfo.setSettlement_total_fee(settlement_total_fee);
payInfo.setBank_type(bank_type);
payInfo.setCoupon_fee("0");
int result = wxPayService.updatePayInfo(payInfo);
if(result<=0){
return_data.put("return_code", "FAIL");
return_data.put("return_msg", "更新订单失败");
return WeixinUtil.GetMapToXML(return_data);
}else{
UserOrderInfo orderInfo = new UserOrderInfo();
orderInfo.setId(payInfo.getOrderId());
orderInfo.setStatus(2);
result = wxPayService.updateOrderInfo(orderInfo);
if(result<=0){
return_data.put("return_code", "FAIL");
return_data.put("return_msg", "更新订单失败");
return WeixinUtil.GetMapToXML(return_data);
}else{
return_data.put("return_code", "SUCCESS");
return_data.put("return_msg", "OK");
return WeixinUtil.GetMapToXML(return_data);
}
}
}
}
}else{//支付失败,更新支付结果
if(payInfo!=null){
payInfo.setResult_code(result_code);
payInfo.setPayStatus(5);
payInfo.setErr_code(map.get("err_code").toString());
payInfo.setErr_code_des(map.get("err_code_des").toString());
wxPayService.updatePayInfo(payInfo);
}
return_data.put("return_code", "FAIL");
return_data.put("return_msg",map.get("return_msg").toString());
return WeixinUtil.GetMapToXML(return_data);
}
}
}
}else{
return_data.put("return_code", "FAIL");
return_data.put("return_msg", "签名错误");
}
String xml = WXPayUtil.GetMapToXML(return_data);
log.error("支付通知回调结果:"+xml);
return xml;
}
}
前端唤起微信支付,看jsp代码
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn"%>
<c:set var="BS" value="${pageContext.request.contextPath}"></c:set>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>支付页面</title>
<script type="text/javascript" src="${BS}/js/jquery-1.7.2.min.js"></script>
</head>
<input type="hidden" id="weixinOperId" value="用户operId">
<script type="text/javascript">
var phoneWidth = parseInt(window.screen.width);
var phoneScale = phoneWidth/640;
var ua = navigator.userAgent;
if (/Android (\d+\.\d+)/.test(ua)){
var version = parseFloat(RegExp.$1);
if(version>2.3){
document.write("<meta name=\"viewport\" content=\"width=device-width,initial-scale=1.0, minimum-scale = 1.0, maximum-scale = "+phoneScale+", target-densitydpi=device-dpi\">");
}else{
document.write("<meta name=\"viewport\" content=\"width=device-width, target-densitydpi=device-dpi\">");
}
}else{
document.write("<meta name=\"viewport\" content=\"width=device-width,minimum-scale=1.0,maximum-scale=1.0,user-scalable=no,target-densitydpi=device-dpi\">");
}

function initPay(powerStationId,userId){
if(!is_weixin()){
alert("请在微信客户端打开该链接");
}else if(!weixin_version()){
alert("你微信版本太低,不支持微信支付功能,请先更新你的微信");
}else{
if(typeof WeixinJSBridge == "undefined"){
if( document.addEventListener ){
document.addEventListener('WeixinJSBridgeReady', initPay, false);
}else if (document.attachEvent){
document.attachEvent('WeixinJSBridgeReady', initPay);
document.attachEvent('onWeixinJSBridgeReady', initPay);
}
}else{
toPay(powerStationId,userId);
}
}
}

function toPay(powerStationId,userId){
$.ajax({
url : "/"+getProjectName()+"/pay/toPayInit",
type:"POST",
dataType : 'json', // 服务器返回的格式,可以是json或xml等
data:{
payMoney:1,
userWeixinOpenId:'用户operId'
},
success : function(result) { // 服务器响应成功时的处理函数
if(result.result==1){//插入支付记录
var paySign = result.paySign;
var prepay_id = result.prepay_id;
var nonceStr = result.noncestr;
var timestamp = result.timestamp;
var unifiedOrderRequest = result.unifiedOrderRequest;
var spbill_create_ip = unifiedOrderRequest.spbill_create_ip;
var detail = unifiedOrderRequest.detail;
var out_trade_no = unifiedOrderRequest.out_trade_no;
$.ajax({
url : "/"+getProjectName()+"/pay/toSavePayInfo",
type:"POST",
dataType : 'json', // 服务器返回的格式,可以是json或xml等
data:{
spbill_create_ip:spbill_create_ip,
detail:detail,
out_trade_no:out_trade_no,
total_fee:1,
powerStationId:powerStationId,
userId:userId,
order_type:1
},
success : function(result) { // 服务器响应成功时的处理函数
if(result>0){//插入支付记录
onBridgeReady(paySign,prepay_id,nonceStr,timestamp);
}
},
error : function(data, status, e) { // 服务器响应失败时的处理函数
$.toptip("系统出错,请联系系统运营商", 'error');
}
});
}else{
$.toptip("初始化支付接口失败,请联系系统运营商", 'error');
}
},
error : function(data, status, e) { // 服务器响应失败时的处理函数
$.toptip("初始化支付接口失败,请联系系统运营商", 'error');
}
});
}

function onBridgeReady(paySign,prepay_id,nonceStr,timestamp){
var weixinOperId = $("#weixinOperId").val();
WeixinJSBridge.invoke(
'getBrandWCPayRequest', {
"appId":weixinOperId, //公众号名称,由商户传入
"timeStamp":timestamp, //时间戳,自1970年以来的秒数
"nonceStr":nonceStr, //随机串
"package":"prepay_id="+prepay_id,
"signType":"MD5", //微信签名方式:
"paySign":paySign //微信签名 (这个签名获取看后台)
},
function(res){
// 使用以上方式判断前端返回,微信团队郑重提示:res.err_msg将在用户支付成功后返回 ok,但并不保证它绝对可靠。
if(res.err_msg == "get_brand_wcpay_request:ok" ) {
alert("支付成功", 'success');
}else if(res.err_msg == "get_brand_wcpay_request:cancel" ) {
alert("用户取消", 'success');
}
}
);
}
</script>
<body>
<div id="addressArea" style="min-height:526px;">
<section class="SelectCityWrap" style="width:98%;">
<section class="content">
<div class="nav">
<a class="" nav="nav_1" onclick="initPay(11,1)">马上支付</a>
</div>
</section>
</section>
</div>
</body>
</html>
到此全部搞定,3个封装数据类,2个工具类,一个controller,一个jsp调用,jsp结果操作提示是用jQuery WeUI插件,很不错的一个手机网站开发插件。
如有不解或者逻辑不通的地方,欢迎评论区留言。
最后附上微信开发系列的目录链接玩转微信公众号开发目录-持续更新