一、消息格式
<xml> <ToUserName><![CDATA[toUser]]></ToUserName> <FromUserName><![CDATA[fromUser]]></FromUserName> <CreateTime>1348831860</CreateTime> <MsgType><![CDATA[text]]></MsgType> <Content><![CDATA[this is a test]]></Content> <MsgId>1234567890123456</MsgId> </xml>
| 参数 | 描述 |
|---|---|
| ToUserName | 开发者微信号 |
| FromUserName | 发送方帐号（一个OpenID） |
| CreateTime | 消息创建时间 （整型） |
| MsgType | text |
| Content | 文本消息内容 |
| MsgId | 消息id，64位整型 |
二、编写消息类实体，代码如下：
BaseMessage.java ---基础消息类
package com.weixin.message;
/**
* 消息实体类
* @author Code猿猿
*
*/
public class BaseMessage {
/**
* 开发者微信号
*/
public String ToUserName;
/**
* 发送方帐号（一个OpenID）
*/
public String FromUserName;
/**
* 消息创建时间 （整型）
*/
public long CreateTime;
/**
* text
*/
public String MsgType ;
public String getToUserName() {
return ToUserName;
}
public void setToUserName(String toUserName) {
ToUserName = toUserName;
}
public String getFromUserName() {
return FromUserName;
}
public void setFromUserName(String fromUserName) {
FromUserName = fromUserName;
}
public long getCreateTime() {
return CreateTime;
}
public void setCreateTime(long createTime) {
CreateTime = createTime;
}
public String getMsgType() {
return MsgType;
}
public void setMsgType(String msgType) {
MsgType = msgType;
}
}
TextMessage.java ---文本消息
package com.weixin.message;
/**
* 文本消息
* @author Zhangsy
*
*/
public class TextMessage extends BaseMessage {
/**
* 文本消息内容
*/
public String Content;
/**
* 消息id，64位整型
*/
public long MsgId ;
public String getContent() {
return Content;
}
public void setContent(String content) {
Content = content;
}
public long getMsgId() {
return MsgId;
}
public void setMsgId(long msgId) {
MsgId = msgId;
}
}
三、编写消息类（读取xml）
MessageUtil.java --》解析接收的xml信息、封装返回的xml信息
package com.weixin.util;
import java.io.IOException;
import java.io.InputStream;
import java.io.Writer;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Pattern;
import javax.servlet.http.HttpServletRequest;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
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;
import com.weixin.message.TextMessage;
/**
* 对消息的处理
* @author Code猿猿
*
*/
public class MessageUtil {
/**
* text
*/
public static final String RESP_MESSAGE_TYPE_TEXT = "text";
/**
* music
*/
public static final String RESP_MESSAGE_TYPE_MUSIC = "music";
/**
* news
*/
public static final String RESP_MESSAGE_TYPE_NEWS = "news";
/**
* text
*/
public static final String REQ_MESSAGE_TYPE_TEXT = "text";
/**
* image
*/
public static final String REQ_MESSAGE_TYPE_IMAGE = "image";
/**
* link
*/
public static final String REQ_MESSAGE_TYPE_LINK = "link";
/**
* location
*/
public static final String REQ_MESSAGE_TYPE_LOCATION = "location";
/**
* voice
*/
public static final String REQ_MESSAGE_TYPE_VOICE = "voice";
/**
* video
*/
public static final String REQ_MESSAGE_TYPE_VIDEO = "video";
/**
* shortvideo
*/
public static final String REQ_MESSAGE_TYPE_SHORTVIDEO = "shortvideo";
/**
* event
*/
public static final String REQ_MESSAGE_TYPE_EVENT = "event";
/**
* subscribe
*/
public static final String EVENT_TYPE_SUBSCRIBE = "subscribe";
/**
* unsubscribe
*/
public static final String EVENT_TYPE_UNSUBSCRIBE = "unsubscribe";
/**
* CLICK
*/
public static final String EVENT_TYPE_CLICK = "CLICK";
public static Map<String,String> parseXml(HttpServletRequest request){
Map<String,String> messageMap=new HashMap<String, String>();
InputStream inputStream=null;
try {
//读取request Stream信息
inputStream=request.getInputStream();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
SAXReader reader = new SAXReader();
Document document=null;
try {
document = reader.read(inputStream);
} catch (DocumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Element root=document.getRootElement();
List<Element> elementsList=root.elements();
for(Element e:elementsList){
messageMap.put(e.getName(),e.getText());
}
try {
inputStream.close();
inputStream=null;
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
return messageMap;
}
/**
* 转换文本消息
*
* @param textMessage
*
* @return xml
*/
public static String textMessageToXml(TextMessage textMessage) {
xstream.alias("xml", textMessage.getClass());
return xstream.toXML(textMessage);
}
/**
*
* 定义xstream让value自动加上CDATA标签
*/
private static XStream xstream = new XStream(new XppDriver() {
public HierarchicalStreamWriter createWriter(Writer out) {
return new PrettyPrintWriter(out) {
boolean cdata = false;
@SuppressWarnings("unchecked")
public void startNode(String name, Class clazz) {
if (!name.equals("xml")) {
char[] arr = name.toCharArray();
if (arr[0] >= ‘a‘ && arr[0] <= ‘z‘) {
// arr[0] -= ‘a‘ - ‘A‘;
arr[0] = (char) ((int) arr[0] - 32);
}
name = new String(arr);
}
super.startNode(name, clazz);
}
@Override
public void setValue(String text) {
if (text != null && !"".equals(text)) {
Pattern patternInt = Pattern
.compile("[0-9]*(\\.?)[0-9]*");
Pattern patternFloat = Pattern.compile("[0-9]+");
if (patternInt.matcher(text).matches()
|| patternFloat.matcher(text).matches()) {
cdata = false;
} else {
cdata = true;
}
}
super.setValue(text);
}
protected void writeText(QuickWriter writer, String text) {
if (cdata) {
writer.write("<![CDATA[");
writer.write(text);
writer.write("]]>");
} else {
writer.write(text);
}
}
};
}
});
}
四、修改Servlet中的Post方法，加入如下代码：
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("UTF-8");
response.setCharacterEncoding("UTF-8");
Map<String,String> message=MessageUtil.parseXml(request);
String messageType=message.get("MsgType");
if(messageType.equals(MessageUtil.REQ_MESSAGE_TYPE_TEXT)){
//接收的是文本消息
//打印接收所有参数
System.out.println("ToUserName："+message.get("ToUserName"));
System.out.println("FromUserName："+message.get("FromUserName"));
System.out.println("CreateTime："+message.get("CreateTime"));
System.out.println("MsgType："+message.get("MsgType"));
System.out.println("Content："+message.get("Content"));
System.out.println("MsgId："+message.get("MsgId"));
String req_content=message.get("Content");
String res_content="";
//组装回复消息
//我们做个小实验
//接收内容：你好 回复：你好
//接收内容：大家好 回复：大家好
//接收内容：同志们好 回复：为人民服务
if("你好".equals(req_content)){
res_content="你好";
}else if ("大家好".equals(req_content)){
res_content="大家好";
}else if("同志们好".equals(req_content)){
res_content="为人民服务";
}else{
//否则原样输出输入内容
res_content=req_content;
}
TextMessage textMessage=new TextMessage();
textMessage.setToUserName(message.get("FromUserName")); //这里的ToUserName 是刚才接收xml中的FromUserName
textMessage.setFromUserName(message.get("ToUserName")); //这里的FromUserName 是刚才接收xml中的ToUserName 这里一定要注意，否则会出错
textMessage.setCreateTime(new Date().getTime());
textMessage.setContent(res_content);
textMessage.setMsgType(messageType);
String xml=MessageUtil.textMessageToXml(textMessage);
System.out.println("xml:"+xml);
PrintWriter out = response.getWriter();
out.print(xml);
out.close();
}
五、部署测试
向公众号发送信息，看是否能够正常返回信息。
给各位推荐一个在线测试的平台：http://debug.fangbei.org/
操作步骤：
录入我们接入微信平台的URL和TOKEN
选择消息类型：文本
内容：输入要发送给公众号的内容
在右侧可看到效果的预览。