微信公众平台开发中使用Java如何实现一个消息回复功能

本篇文章给大家分享的是有关微信公众平台开发中使用Java如何实现一个消息回复功能，小编觉得挺实用的，因此分享给大家学习，希望大家阅读完这篇文章后可以有所收获，话不多说，跟着小编一起来看看吧。

（一）回复文本消息

在前面我们已经完成了对消息的分类和回复消息实体的建立，这里回复文本消息需要用到的就是我们的TextMessage，我们把回复文本消息在【文本消息】类型中给出回复！在我们做消息回复的时候需要设置消息的接收人ToUserName（openid）、消息的发送方FromUserName、消息类型MsgType、创建时间CreateTime以及消息体Content，由于我们我们的消息回复格式是需要为xml，所以最终我们需要将其装换成xml再做返回输出！

首先我们在工具类MessageUtil的代码做出部分修改和添加，实现最后版本为：

package com.cuiyongzhi.wechat.util; import java.io.InputStream;import java.io.Writer;import java.util.HashMap;import java.util.List;import java.util.Map; import javax.servlet.Http.httpservletRequest; import org.dom4j.D ocument;import org.dom4j.Element;import org.dom4j.io.SAXReader; import com.cuiyongzhi.wechat.message.resp.Article;import com.cuiyongzhi.wechat.message.resp.ImageMessage;import com.cuiyongzhi.wechat.message.resp.MusicMessage;import com.cuiyongzhi.wechat.message.resp.NewsMessage;import com.cuiyongzhi.wechat.message.resp.TextMessage;import com.cuiyongzhi.wechat.message.resp.VideoMessage;import com.cuiyongzhi.wechat.message.resp.VoiceMessage;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; public class MessageUtil {   public static final String RESP_MESSAGE_TYPE_TEXT = "text";   public static final String RESP_MESSAGE_TYPE_MUSIC = "music";   public static final String RESP_MESSAGE_TYPE_NEWS = "news";   public static final String RESP_MESSAGE_TYPE_Image = "image";   public static final String RESP_MESSAGE_TYPE_Voice = "voice";   public static final String RESP_MESSAGE_TYPE_Video = "video";   public static final String REQ_MESSAGE_TYPE_TEXT = "text";   public static final String REQ_MESSAGE_TYPE_IMAGE = "image";   public static final String REQ_MESSAGE_TYPE_LINK = "link";   public static final String REQ_MESSAGE_TYPE_LOCATION = "location";   public static final String REQ_MESSAGE_TYPE_VOICE = "voice";   public static final String REQ_MESSAGE_TYPE_VIDEO = "video";   public static final String REQ_MESSAGE_TYPE_EVENT = "event";   public static final String EVENT_TYPE_SUBSCRIBE = "subscribe";   public static final String EVENT_TYPE_UNSUBSCRIBE = "unsubscribe";   public static final String EVENT_TYPE_CLICK = "CLICK";   public static final String EVENT_TYPE_VIEW = "VIEW";   public static final String EVENT_TYPE_LOCATION = "LOCATION";   public static final String EVENT_TYPE_SCAN = "SCAN";   @SuppressWarnings("unchecked") public static Map<String, String> parseXml(HttpServletRequest request)   throws Exception {  // 将解析结果存储在HashMap中  Map<String, String> map = new HashMap<String, String>();  // 从request中取得输入流  InputStream inputStream = request.getInputStream();  // 读取输入流  SAXReader reader = new SAXReader();  Document document = reader.read(inputStream);  // 得到xml根元素  Element root = document.getRootElement();  // 得到根元素的所有子节点  List<Element> elementList = root.elements();   // 遍历所有子节点  for (Element e : elementList)   map.put(e.getName(), e.getText());   // 释放资源  inputStream.close();  inputStream = null;   return map; }   public static String textMessageToXml(TextMessage textMessage) {  xstream.alias("xml", textMessage.getClass());  return xstream.toXML(textMessage); }   public static String newsMessageToXml(NewsMessage newsMessage) {  xstream.alias("xml", newsMessage.getClass());  xstream.alias("item", new Article().getClass());  return xstream.toXML(newsMessage); }   public static String imageMessageToXml(ImageMessage imageMessage) {  xstream.alias("xml", imageMessage.getClass());  return xstream.toXML(imageMessage); }   public static String voiceMessageToXml(VoiceMessage voiceMessage) {  xstream.alias("xml", voiceMessage.getClass());  return xstream.toXML(voiceMessage); }   public static String videoMessageToXml(VideoMessage videoMessage) {  xstream.alias("xml", videoMessage.getClass());  return xstream.toXML(videoMessage); }   public static String musicMessageToXml(MusicMessage musicMessage) {  xstream.alias("xml", musicMessage.getClass());  return xstream.toXML(musicMessage); }   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;     @SuppressWarnings("rawtypes")    public void startnode(String name, Class clazz) {     super.startNode(name, clazz);    }     protected void writeText(QuickWriter writer, String text) {     if (cdata) {      writer.write("<![CDATA[");      writer.write(text);      writer.write("]]>");     } else {      writer.write(text);     }    }   };  } });}