Android微信支付，通知回调方法

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

import javax.servlet.ServletException;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.lang.StringUtils;
import org.apache.log4j.Logger;
import org.jdom.Element;
import org.jdom.input.SAXBuilder;
import org.xml.sax.InputSource;

import com.tenpay.ResponseHandler;
import com.tenpay.util.TenpayUtil;

/**
* 微信回调Servlet
*
*/
public class WXPayRspServlet extends HttpServlet {

private static final long serialVersionUID = -3523419191502630036L;
private final static Logger log = Logger.getLogger(<span style="font-family: Arial, Helvetica, sans-serif;">WXPayRspServlet</span><span style="font-family: Arial, Helvetica, sans-serif;">.class);</span>

@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
ServletInputStream in = req.getInputStream();
ResponseHandler resHandler = new ResponseHandler(req, resp);
String resXml = "<xml>" + "<return_code><![CDATA[FAIL]]></return_code>" + "<return_msg><![CDATA[报文为空]]></return_msg>" + "</xml> ";
try{
int size = req.getContentLength();
byte[] bdata = new byte[size];
in.read(bdata);
String xmlstring = new String(bdata,TenpayUtil.getCharacterEncoding(req, resp));
log.info("****** back data xml *******\n");
log.info(xmlstring);
if(!StringUtils.isEmpty(xmlstring)){
Map paramMap = parseXmlToMap(xmlstring);
/*
WxPayResult wpr = new WxPayResult();
wpr.setAppid(m.get("appid").toString());
wpr.setBankType(m.get("bank_type").toString());
wpr.setCashFee(m.get("cash_fee").toString());
wpr.setFeeType(m.get("fee_type").toString());
wpr.setIsSubscribe(m.get("is_subscribe").toString());
wpr.setMchId(m.get("mch_id").toString());
wpr.setNonceStr(m.get("nonce_str").toString());
wpr.setOpenid(m.get("openid").toString());
wpr.setOutTradeNo(m.get("out_trade_no").toString());
wpr.setResultCode(m.get("result_code").toString());
wpr.setReturnCode(m.get("return_code").toString());
wpr.setSign(m.get("sign").toString());
wpr.setTimeEnd(m.get("time_end").toString());
wpr.setTotalFee(m.get("total_fee").toString());
wpr.setTradeType(m.get("trade_type").toString());
wpr.setTransactionId(m.get("transaction_id").toString());
*/
String result_code = paramMap.get("result_code").toString();

if("SUCCESS".equals(result_code.toUpperCase())){
//根据自身业务编写代码
}
}else{
resXml = "<xml>" + "<return_code><![CDATA[FAIL]]></return_code>" + "<return_msg><![CDATA[报文为空]]></return_msg>" + "</xml> ";
log.error("微信返回报文为空");
}

}catch(Exception e){
log.error(e.getMessage(), e);
e.printStackTrace();
}
log.info(resXml);
resHandler.sendToCFT(resXml);

}

protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doGet(req, resp);
}

private Map parseXmlToMap(String xml) {
Map retMap = new HashMap();
try {
StringReader read = new StringReader(xml);
// 创建新的输入源SAX 解析器将使用 InputSource 对象来确定如何读取 XML 输入
InputSource source = new InputSource(read);
// 创建一个新的SAXBuilder
SAXBuilder sb = new SAXBuilder();
// 通过输入源构造一个Document
org.jdom.Document doc =  sb.build(source);
Element root = (Element) doc.getRootElement();// 指向根节点
List<Element> es = root.getChildren();
if (es != null && es.size() != 0) {
for (Element element : es) {
retMap.put(element.getName(), element.getValue());
}
}
} catch (Exception e) {
e.printStackTrace();
}
return retMap;
}
}

public void sendToCFT(String msg) throws IOException {
String strHtml = msg;
PrintWriter out = this.getHttpServletResponse().getWriter();
out.println(strHtml);
out.flush();
out.close();

}

<span style="white-space:pre">	</span>WxPayResult wpr = new WxPayResult();

sendToCFT方法为响应微信方法，即<pre name="code" class="java"><return_code><![CDATA[SUCCESS]]></return_code>