微信消息处理JAXP-dom解析

package cn.lihainan.test;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;

import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;


import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

import org.w3c.dom.Document;
import org.w3c.dom.Node;


public class Demo1 extends HttpServlet {
    public void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException { 
        try {    // 将请求、响应的编码均设置为UTF-8（防止中文乱码）
        request.setCharacterEncoding("utf-8");  
        response.setContentType("textml;charset=utf-8");
        InputStream inputStream = request.getInputStream();
        


        String result = readFromInputStream(inputStream);
        
        
        
        PrintWriter out = response.getWriter();

        out.println("原始消息：");

        out.println(result);

        //解析 建立document解析
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder;
        builder = factory.newDocumentBuilder();
        
        InputStream xmlStream = new ByteArrayInputStream(result.getBytes("UTF-8"));
        Document document =  builder.parse(xmlStream);
        //定义节点    根据节点从document中找到要输出的 
        Node ToUserName = document.getElementsByTagName("ToUserName").item(0);      
        System.out.println(ToUserName.getTextContent());
        
        Node FromUserName = document.getElementsByTagName("FromUserName").item(0);      
        System.out.println(FromUserName.getTextContent());
        
        Node MsgType= document.getElementsByTagName("MsgType").item(0);      
        System.out.println(MsgType.getTextContent());
        
        Node Content = document.getElementsByTagName("Content").item(0);      
        System.out.println(Content.getTextContent());
        
        Node MsgId= document.getElementsByTagName("MsgId").item(0);      
        System.out.println(MsgId.getTextContent());
        
        
        out.println();
        //输出
        out.println("解析结果：");
        out.print("FromUserName(来自):");
        out.println(FromUserName.getTextContent());
        out.print("ToUserName(发送至):");
        out.println(ToUserName.getTextContent());
        out.print("CreateTime(时间):");
        
        Node createTime= document.getElementsByTagName("CreateTime").item(0);
        int t = Integer.parseInt(createTime.getTextContent());
        SimpleDateFormat format = new SimpleDateFormat("yyyy/MM/dd hh:mm:ss");
        out.println(format.format((long)t*1000L));
        out.print("MsgType(消息类型):");
        out.println(MsgType.getTextContent());
        out.print("Content(文本内容):");
        out.println(Content.getTextContent());
        out.print("MsgId(文件消息标识号):");
        out.println(MsgId.getTextContent());
        } catch (ParserConfigurationException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        }
    }
    
    //将输入流InputStream变为String
    public String readFromInputStream(InputStream in) throws IOException {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = -1;
        while ((len = in.read(buffer)) != -1) {
            baos.write(buffer, 0, len);
        }
        baos.close();
        in.close();
        // 解析内容     看网上更改 输出中文乱码  但是未解决  已知输入流为gbk  输出为utf-8  求如何转换
        byte[] lens = baos.toByteArray();
        String result = new String(lens,"UTF-8");
        
        return result;
    
    }
}