java开发微信公众号支付（JSAPI）

package com.github.wxpay.controller; import com.github.wxpay.sdk.WXPayConstants;
import com.github.wxpay.sdk.WXPayUtil;
import com.github.wxpay.util.Constant;
import com.github.wxpay.util.HttpRequestUtil;
import com.github.wxpay.util.OrderUtil;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody; import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.util.HashMap;
import java.util.Map;
import org.springframework.web.bind.annotation.RequestMapping;
import com.github.wxpay.sdk.WXPayConstants.SignType; public class WxPayController { /**
*
* @Description 微信浏览器内微信支付/公众号支付(JSAPI)
*/
@RequestMapping(value = "/orders",method = RequestMethod.GET)
@ResponseBody
public Map orders(HttpServletRequest request){
try {
Map<String, String> paramMap = new HashMap<String, String>();
HttpSession session = request.getSession();
String wxopenid = session.getAttribute("openid") == null ? null : session.getAttribute("openid").toString();
//在商户平台的账户中心下:需要用户自行下载证书及安装
String key = Constant.signCustomerKey;
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();
}
if (ip.indexOf(",") != -1) {
String[] ips = ip.split(",");
ip = ips[0].trim();
}
paramMap.put("appid", Constant.APPIDS[0]);
paramMap.put("mch_id", "");
paramMap.put("nonce_str", WXPayUtil.generateNonceStr());
paramMap.put("body", "测试订单XX矿泉水");
paramMap.put("openid", wxopenid);
paramMap.put("out_trade_no", OrderUtil.orderNumber());
paramMap.put("spbill_create_ip", ip);
paramMap.put("total_fee", "0.01");
paramMap.put("notify_url", "http://127.0.0.1:8080/alipay.trade.page.pay-JAVA-UTF-8/notify_url.jsp");// 此路径是微信服务器调用支付结果通知路径
paramMap.put("trade_type", "JSAPI");
String sign = WXPayUtil.generateSignature(paramMap,key,SignType.MD5);
paramMap.put("sign", sign); // 将所有参数(map)转xml格式
String mapToXml = WXPayUtil.mapToXml(paramMap);
System.out.println(mapToXml);
// 统一下单 https://api.mch.weixin.qq.com/pay/unifiedorder
String unifiedorder_url = "https://api.mch.weixin.qq.com/pay/unifiedorder";
// 发送post请求"统一下单接口"返回预支付id:prepay_id
String xmlStr = HttpRequestUtil.sendPost(unifiedorder_url,mapToXml); Map<String,String> XmlToMap = WXPayUtil.xmlToMap(xmlStr);
// 以下内容是返回前端页面的json数据
String prepay_id = ""; // 预支付ID
if (xmlStr.indexOf("SUCCESS") != -1) {
Map<String, String> map = WXPayUtil.xmlToMap(xmlStr);
prepay_id = map.get("prepay_id");
}
Map<String, String> payMap = new HashMap<String, String>();
XmlToMap.put("appId", Constant.APPIDS[0]);
XmlToMap.put("timeStamp", WXPayUtil.getCurrentTimestamp()+"");
XmlToMap.put("nonceStr", WXPayUtil.generateNonceStr());
XmlToMap.put("signType", "MD5");
XmlToMap.put("package", "prepay_id=" + prepay_id);
String paySign = WXPayUtil.generateSignature(payMap, key);
payMap.put("paySign", paySign);
return XmlToMap;
}catch (Exception e){
e.printStackTrace();
}
return null;
}
}

package com.github.wxpay.util; import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.URLConnection;
import java.util.List;
import java.net.URL;
import java.util.Map; public class HttpRequestUtil {
/**
* 向指定URL发送GET方法的请求
*
* @param url
* 发送请求的URL
* @param param
* 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
* @return URL 所代表远程资源的响应结果
*/
public static String sendGet(String url, String param) {
String result = "";
BufferedReader in = null;
try {
String urlNameString = url + "?" + param;
URL realUrl = new URL(urlNameString);
// 打开和URL之间的连接
URLConnection connection = realUrl.openConnection();
// 设置通用的请求属性
connection.setRequestProperty("accept", "*/*");
connection.setRequestProperty("connection", "Keep-Alive");
connection.setRequestProperty("user-agent",
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
// 建立实际的连接
connection.connect();
// 获取所有响应头字段
Map<String, List<String>> map = connection.getHeaderFields();
// 遍历所有的响应头字段
for (String key : map.keySet()) {
System.out.println(key + "--->" + map.get(key));
}
// 定义 BufferedReader输入流来读取URL的响应
in = new BufferedReader(new InputStreamReader(
connection.getInputStream()));
String line;
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
System.out.println("发送GET请求出现异常！" + e);
e.printStackTrace();
}
// 使用finally块来关闭输入流
finally {
try {
if (in != null) {
in.close();
}
} catch (Exception e2) {
e2.printStackTrace();
}
}
return result;
} /**
* 向指定 URL 发送POST方法的请求
*
* @param url
* 发送请求的 URL
* @param param
* 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
* @return 所代表远程资源的响应结果
*/
public static String sendPost(String url, String param) {
PrintWriter out = null;
BufferedReader in = null;
String result = "";
try {
URL realUrl = new URL(url);
// 打开和URL之间的连接
URLConnection conn = realUrl.openConnection();
// 设置通用的请求属性
conn.setRequestProperty("accept", "*/*");
conn.setRequestProperty("connection", "Keep-Alive");
conn.setRequestProperty("user-agent",
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
// 发送POST请求必须设置如下两行
conn.setDoOutput(true);
conn.setDoInput(true);
// 获取URLConnection对象对应的输出流
out = new PrintWriter(conn.getOutputStream());
// 发送请求参数
out.print(param);
// flush输出流的缓冲
out.flush();
// 定义BufferedReader输入流来读取URL的响应
in = new BufferedReader(
new InputStreamReader(conn.getInputStream()));
String line;
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
System.out.println("发送 POST 请求出现异常！"+e);
e.printStackTrace();
}
//使用finally块来关闭输出流、输入流
finally{
try{
if(out!=null){
out.close();
}
if(in!=null){
in.close();
}
}
catch(IOException ex){
ex.printStackTrace();
}
}
return result;
}
}

package com.github.wxpay.util;import com.github.wxpay.sdk.WXPayUtil;public class OrderUtil { public static String orderNumber(){
int r1 = (int)(Math.random()*10);
int r2 = (int)(Math.random()*10);
long now = WXPayUtil.getCurrentTimestampMs();
String paymentID = String.valueOf(r1)+String.valueOf(r2)+String.valueOf(now);
return paymentID;
}
}