微信公众平台现在推出自动回复消息接口,但是由于是接口内容用的是PHP语言写的,很多地方操作起来让本人这个对java比较熟悉的小伙很别扭,所以仿照PHP的接口代码做了一套jsp语言编写的接口。
首先先把整个接口代码贴出来做下比较,然后我们再分析代码:
PHP:
<?php /** * wechat php test */ //define your token define("TOKEN", "weixin"); $wechatObj = new wechatCallbackapiTest(); $wechatObj->valid(); class wechatCallbackapiTest { public function valid() { $echoStr = $_GET["echostr"]; //valid signature , option if($this->checkSignature()){ echo $echoStr; exit; } } public function responseMsg() { //get post data, May be due to the different environments $postStr = $GLOBALS["HTTP_RAW_POST_DATA"]; //extract post data if (!empty($postStr)){ $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA); $fromUsername = $postObj->FromUserName; $toUsername = $postObj->ToUserName; $keyword = trim($postObj->Content); $time = time(); $textTpl = "<xml> <ToUserName><![CDATA[%s]]></ToUserName> <FromUserName><![CDATA[%s]]></FromUserName> <CreateTime>%s</CreateTime> <MsgType><![CDATA[%s]]></MsgType> <Content><![CDATA[%s]]></Content> <FuncFlag>0</FuncFlag> </xml>"; if(!empty( $keyword )) { $msgType = "text"; $contentStr = "Welcome to wechat world!"; $resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr); echo $resultStr; }else{ echo "Input something..."; } }else { echo ""; exit; } } private function checkSignature() { $signature = $_GET["signature"]; $timestamp = $_GET["timestamp"]; $nonce = $_GET["nonce"]; $token = TOKEN; $tmpArr = array($token, $timestamp, $nonce); sort($tmpArr); $tmpStr = implode( $tmpArr ); $tmpStr = sha1( $tmpStr ); if( $tmpStr == $signature ){ return true; }else{ return false; } } } ?>
JAVA:
<%@page import="java.util.Date"%> <%@page import="org.dom4j.Element"%> <%@page import="org.dom4j.DocumentHelper"%> <%@page import="org.dom4j.Document"%> <%@page import="java.io.IOException"%> <%@page import="java.io.InputStreamReader"%> <%@page import="java.io.BufferedReader"%> <%@page import="java.io.Reader"%> <%@page import="java.security.MessageDigest"%> <%@page import="java.util.Arrays"%> <%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <% //WeiXinHandler为内部类不能使用非final类型的对象 final String TOKEN="weixin"; final HttpServletRequest final_request=request; final HttpServletResponse final_response=response; %> <% class WeiXinHandler{ public void valid(){ String echostr=final_request.getParameter("echostr"); if(null==echostr||echostr.isEmpty()){ responseMsg(); }else{ if(this.checkSignature()){ this.print(echostr); }else{ this.print("error"); } } } //自动回复内容 public void responseMsg(){ String postStr=null; try{ postStr=this.readStreamParameter(final_request.getInputStream()); }catch(Exception e){ e.printStackTrace(); } //System.out.println(postStr); if (null!=postStr&&!postStr.isEmpty()){ Document document=null; try{ document = DocumentHelper.parseText(postStr); }catch(Exception e){ e.printStackTrace(); } if(null==document){ this.print(""); return; } Element root=document.getRootElement(); String fromUsername = root.elementText("FromUserName"); String toUsername = root.elementText("ToUserName"); String keyword = root.elementTextTrim("Content"); String time = new Date().getTime()+""; String textTpl = "<xml>"+ "<ToUserName><![CDATA[%1$s]]></ToUserName>"+ "<FromUserName><![CDATA[%2$s]]></FromUserName>"+ "<CreateTime>%3$s</CreateTime>"+ "<MsgType><![CDATA[%4$s]]></MsgType>"+ "<Content><![CDATA[%5$s]]></Content>"+ "<FuncFlag>0</FuncFlag>"+ "</xml>"; if(null!=keyword&&!keyword.equals("")) { String msgType = "text"; String contentStr = "Welcome to wechat world!"; String resultStr = textTpl.format(textTpl, fromUsername, toUsername, time, msgType, contentStr); this.print(resultStr); }else{ this.print("Input something..."); } }else { this.print(""); } } //微信接口验证 public boolean checkSignature(){ String signature = final_request.getParameter("signature"); String timestamp = final_request.getParameter("timestamp"); String nonce = final_request.getParameter("nonce"); String token=TOKEN; String[] tmpArr={token,timestamp,nonce}; Arrays.sort(tmpArr); String tmpStr=this.ArrayToString(tmpArr); tmpStr=this.SHA1Encode(tmpStr); if(tmpStr.equalsIgnoreCase(signature)){ return true; }else{ return false; } } //向请求端发送返回数据 public void print(String content){ try{ final_response.getWriter().print(content); final_response.getWriter().flush(); final_response.getWriter().close(); }catch(Exception e){ } } //数组转字符串 public String ArrayToString(String [] arr){ StringBuffer bf = new StringBuffer(); for(int i = 0; i < arr.length; i++){ bf.append(arr[i]); } return bf.toString(); } //sha1加密 public String SHA1Encode(String sourceString) { String resultString = null; try { resultString = new String(sourceString); MessageDigest md = MessageDigest.getInstance("SHA-1"); resultString = byte2hexString(md.digest(resultString.getBytes())); } catch (Exception ex) { } return resultString; } public final String byte2hexString(byte[] bytes) { StringBuffer buf = new StringBuffer(bytes.length * 2); for (int i = 0; i < bytes.length; i++) { if (((int) bytes[i] & 0xff) < 0x10) { buf.append("0"); } buf.append(Long.toString((int) bytes[i] & 0xff, 16)); } return buf.toString().toUpperCase(); } //从输入流读取post参数 public String readStreamParameter(ServletInputStream in){ StringBuilder buffer = new StringBuilder(); BufferedReader reader=null; try{ reader = new BufferedReader(new InputStreamReader(in)); String line=null; while((line = reader.readLine())!=null){ buffer.append(line); } }catch(Exception e){ e.printStackTrace(); }finally{ if(null!=reader){ try { reader.close(); } catch (IOException e) { e.printStackTrace(); } } } return buffer.toString(); } } %> <% WeiXinHandler handler=new WeiXinHandler(); handler.valid(); %>
以上就是PHP接口和JSP接口的所有代码,现在我们来对一些需要注意的地方做下分析:
首先的从总体看的话,jsp要比PHP繁琐一些,因为很多函数需要自己写,像sha1加密,解析xml字符串等都需要自己找第三方的库。
第一点,我们要获取微信公众平台给jsp发送的post或get参数,正常情况下都是用request.getParameter就可以获取到,但是在写的过程中发现PHP是这样获取
$postStr = $GLOBALS["HTTP_RAW_POST_DATA"];这时通过查询一些资料知道这样获取的是无法通过$_GET或$_POST函数得到的” 未识别 MIME 类型的数据“,原始的 POST 数据
(参考:http://blog.csdn.net/china_skag/article/details/7284227)
所以这里使用获取原始数据流的方式来解析post的xml数据
String postStr=null; try{ postStr=this.readStreamParameter(final_request.getInputStream()); }catch(Exception e){ e.printStackTrace(); }
//从输入流读取post参数 public String readStreamParameter(ServletInputStream in){ StringBuilder buffer = new StringBuilder(); BufferedReader reader=null; try{ reader = new BufferedReader(new InputStreamReader(in)); String line=null; while((line = reader.readLine())!=null){ buffer.append(line); } }catch(Exception e){ e.printStackTrace(); }finally{ if(null!=reader){ try { reader.close(); } catch (IOException e) { e.printStackTrace(); } } } return buffer.toString(); }
echo ""; exit;猜想可能需要有个刷新的操作才能把消息response回去,于是找了下response内的一些函数做出以下尝试
//向请求端发送返回数据 public void print(String content){ try{ final_response.getWriter().print(content); final_response.getWriter().flush(); final_response.getWriter().close(); }catch(Exception e){ } }
发现以上做法是可以在微信发送端得到消息的;
第三个,接口描述上说目前只支持80端口的服务端地址,所以我这里的做法是用apache服务器路由到tomcat的jsp上
关于微信公众平台的消息接口的详细介绍,可以参看微信公众平台的官方文档,里面介绍了消息的xml的格式和消息的发送方式等。