微信小程序支付(基于Java实现微信JSAPI支付)：支付，提现，退款

• 添加WXpayCommon类用以具体实现相关功能

package com.karat.cn.wxCommon;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import com.karat.cn.util.WXPay;
import com.karat.cn.util.WXPayConfigImpl;
import com.karat.cn.util.WXPayConstants;
import com.karat.cn.util.WXPayUtil;
import com.karat.cn.vo.VoUnifiedOrderWx;

/**
 * 支付,提现,退款
 * @author 开发
 *
 */
public class WXpayCommon {
    
    private static WXPay wxpay;
    private static WXPayConfigImpl config;
    
    
    public static void WXpayCommonIns() throws Exception {
        config = WXPayConfigImpl.getInstance();
        wxpay = new WXPay(config);
    }
    
    /**
     * 支付
     * @param orderInfo 自己数据库生成的订单
     * @param openid    用户的标识openId
     * @param ip        
     * @param flag
     * @return
     * @throws IOException
     */
    public static VoUnifiedOrderWx payOrderWx(WxWithdrawOrder orderInfo, String openid, String ip, boolean flag) throws IOException {
        VoUnifiedOrderWx voUnifiedOrderWx = null;
        try {
            Map<String, String> respData = null;
            if (flag) {
                HashMap<String, String> data = new HashMap<String, String>();
                data.put("body", orderInfo.getOrderNo());
                data.put("out_trade_no", orderInfo.getOrderNo());//订单号
                data.put("fee_type", "CNY");
                data.put("total_fee", "1");//支付金额（分）
                data.put("spbill_create_ip", ip);
                data.put("notify_url", "******************");//支付成功回调地址
                // 交易类型--JSAPI:公众号支付、NATIVE:原生扫码支付、APP:APP支付
                // 公众号支付
                data.put("trade_type", "JSAPI");//支付方式
                // 设备号--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"
                data.put("device_info", "WEB");
                // 用户openid
                data.put("openid", openid);
                data.put("product_id", "1000" + "");
                
                if (null == wxpay) {
                    WXpayCommonIns();
                }
                respData = wxpay.unifiedOrder(data);//统一下单
                orderInfo.setRemark(respData);
            } else {
                respData = orderInfo.getRemark();
            }
            System.out.println(respData);
            // 返回状态码
            String return_code = respData.get("return_code");
            if (return_code.equals(WXPayConstants.SUCCESS)) {
                // 业务结果
                String result_code = respData.get("result_code");
                if (result_code.equals(WXPayConstants.SUCCESS)) {
                    voUnifiedOrderWx = new VoUnifiedOrderWx();
                    // 时间戳
                    voUnifiedOrderWx.setTimeStamp(BaseToolsUtil.systemtimeLong()/1000 + "");
                    // 随机串
                    voUnifiedOrderWx.setNonceStr(respData.get("nonce_str"));
                    // 数据包
                    voUnifiedOrderWx.setPackageValue("prepay_id=" + respData.get("prepay_id"));
                    
                    // 二次签名
                    HashMap<String, String> dataPay = new HashMap<String, String>();
                    dataPay.put("appId", respData.get("appid"));
                    dataPay.put("nonceStr", voUnifiedOrderWx.getNonceStr());
                    dataPay.put("package", voUnifiedOrderWx.getPackageValue());
                    dataPay.put("timeStamp", voUnifiedOrderWx.getTimeStamp());
                    dataPay.put("signType", "MD5");
                    String sign = WXPayUtil.generateSignature(dataPay, config.getKey());
                    // 签名
                    voUnifiedOrderWx.setSign(sign);
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return voUnifiedOrderWx;
    }
    
    
    /**
     * 企业付款(提现)
     * @param wxWithdrawOrder
     * @param openid    
     * @param ip
     * @throws Exception
     */
    public static void transfers(WxWithdrawOrder wxWithdrawOrder, String openid, String ip) throws Exception {
        HashMap<String, String> data = new HashMap<String, String>();
        // 商户订单号
        data.put("partner_trade_no", wxWithdrawOrder.getOrderNo());
        // 用户openid
        data.put("openid", openid);
        // 校验用户姓名选项
        data.put("check_name", "NO_CHECK");
        // 金额
        data.put("amount", wxWithdrawOrder.getMoney() + "");
        // 企业付款描述信息
        // TODO
        data.put("desc", "提现");
        // Ip地址
        data.put("spbill_create_ip", ip);
            
        if (null == wxpay) {
            WXpayCommonIns();
        }
        String respXml = wxpay.transfers(data);//企业付款
        System.out.println(respXml);
        Map<String, String> respData = WXPayUtil.xmlToMap(respXml);
        wxWithdrawOrder.setRemark(respData);
        wxWithdrawOrder.setRemark2(respXml);
        // 返回状态码
        String return_code = respData.get("return_code");
        System.out.println(return_code);
        if (return_code.equals(WXPayConstants.SUCCESS)) {
            // 业务结果处理
        }
    }
    
    
    /**
     * @description:微信退款业务封装(支付押金退还);
     * @param 　 PayLog order:支付订单信息
     *           Double refundAmount:退款金额
     * @return 微信退款接口返回数据  true 退款成功  false 退款失败
     * @author:FanHaoJian
     * @throws Exception 
     */
    public static Boolean refundOrder(WxWithdrawOrder orderInfo,Double refundAmount) throws Exception{
        if (null == wxpay) {
            WXpayCommonIns();
        }
        HashMap<String, String> data = new HashMap<String, String>();
            data.put("out_trade_no", orderInfo.getOrderNo());
            data.put("out_refund_no", orderInfo.getOrderNo());
            data.put("total_fee", "1000");//价钱分
            data.put("refund_fee", String.valueOf((int)(refundAmount*100)));
            data.put("refund_fee_type", "CNY");
            data.put("op_user_id", config.getMchID());
            try {
                Map<String, String> r = wxpay.refund(data);//订单退款
                System.out.println(r);
                return Boolean.TRUE;
            } catch (Exception e) {
                e.printStackTrace();
            }
        return Boolean.FALSE;
    }
    
}

• 控制层接口

package com.karat.cn.action;

import java.io.BufferedOutputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import com.karat.cn.util.WXPayConfigImpl;
import com.karat.cn.util.WXPayConstants;
import com.karat.cn.util.WXPayUtil;
import com.karat.cn.wxCommon.IpAddressUtil;
import com.karat.cn.wxCommon.WXpayCommon;
import com.karat.cn.wxCommon.WxWithdrawOrder;
/**
 * 接口模板
 * @author 开发
 *
 */
@Controller
@RequestMapping("wx")
public class WxPayAction {
    
    private HttpServletRequest request;
    private HttpServletResponse response;
    private WXPayConfigImpl config;
    /**
     * 支付
     * @return
     */
    @RequestMapping("/pay")
    public String pay(){
        Map<String, String> remark=new HashMap<String, String>();
        //新建订单
        WxWithdrawOrder order=new WxWithdrawOrder("1","1",1,"1","1",remark,"");
        try {
            WXpayCommon.payOrderWx(order, "用户openId",IpAddressUtil.getIpAddr(request), true);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return "";
    }
    /**
     * 微信回调接口notify（支付填写的支付成功回调地址）
     * @throws Exception
     */
    @RequestMapping("/notifyPayWx")
    public void notifyPayWx() throws Exception {
        boolean state = false;
        System.out.println("微信回调");
        InputStream inStream = request.getInputStream();
        ByteArrayOutputStream outSteam = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = 0;
        while ((len = inStream.read(buffer)) != -1) {
            outSteam.write(buffer, 0, len);
        }
        outSteam.close();
        inStream.close();
        String resultXml = new String(outSteam.toByteArray(), "utf-8");
        System.out.println("resultXml:" + resultXml);
        Map<String, String> resultMap = WXPayUtil.xmlToMap(resultXml);
        // 签名验证
        if (WXPayUtil.isSignatureValid(resultXml, config.getKey())) {
            String resXml = "";
            // 业务结果
            String result_code = resultMap.get("result_code");
            if (result_code.equals(WXPayConstants.SUCCESS)) {
                // 订单号
                //String out_trade_no = resultMap.get("out_trade_no");
                // 支付成功处理业务逻辑
                state =true;//根据订单号查询自己数据库该条数据进行业务操作,操作成功返回true
            } 
            if (state) {
                //通知微信.异步确认成功.必写.不然会一直通知后台.八次之后就认为交易失败了.  
                resXml = "<xml>" + "<return_code><![CDATA[SUCCESS]]></return_code>" 
                        + "<return_msg><![CDATA[OK]]></return_msg>" + "</xml> ";
            } else {
                resXml = "<xml>" + "<return_code><![CDATA[FAIL]]></return_code>" 
                        + "<return_msg><![CDATA[报文为空]]></return_msg>" + "</xml> ";
            }
            System.out.println("resXml:" + resultXml);
            BufferedOutputStream out = new BufferedOutputStream(response.getOutputStream());
            out.write(resXml.getBytes());
            out.flush();
            out.close();
        } else {
            // 签名验证失败
            System.out.println("签名验证失败");
        }
    }
    
    /**
     * 退款
     * @return
     */
    @RequestMapping("/returnPay")
    public String returnPay(){
        Map<String, String> remark=new HashMap<String, String>();
        //新建订单
        WxWithdrawOrder order=new WxWithdrawOrder("1","1",1,"1","1",remark,"");
        try {
            WXpayCommon.refundOrder(order,0.01);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return "";
    }
    /**
     * 提现
     * @return
     */
    @RequestMapping("/withdrawDeposit")
    public String withdrawDeposit(){
        Map<String, String> remark=new HashMap<String, String>();
        //新建订单
        WxWithdrawOrder order=new WxWithdrawOrder("1","1",1,"1","1",remark,"");
        try {
            WXpayCommon.transfers(order,"用户openId", "服务器地址");
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return "";
    }
    public HttpServletRequest getRequest() {
        return request;
    }
    public void setRequest(HttpServletRequest request) {
        this.request = request;
    }
    public HttpServletResponse getResponse() {
        return response;
    }
    public void setResponse(HttpServletResponse response) {
        this.response = response;
    }
    
    
    
}

• 接口中主要根据业务逻辑调用WXpayCommon类中的功能实现方法即可。项目中的相关代码，线上可用，copy整理出的未实测(主要需要相关参数测试,不方便)，目测没毛病