Java微信公众平台开发（8） 多媒体消息回复

#获取token的url
tokenUrl=https://api.weixin.qq.com/cgi-bin/token
#永久多媒体文件上传url
mediaUrl=http://file.api.weixin.qq.com/cgi-bin/media/upload?access_token=

package com.cuiyongzhi.wechat.util;
 
import java.io.BufferedReader; 
import java.io.DataInputStream; 
import java.io.DataOutputStream; 
import java.io.File; 
import java.io.FileInputStream; 
import java.io.InputStreamReader; 
import java.io.OutputStream; 
import java.net.HttpURLConnection; 
import java.net.URL; 
import java.util.Iterator; 
import java.util.Map; 
 
import javax.activation.MimetypesFileTypeMap;
import com.cuiyongzhi.web.util.GlobalConstants;
 
/**
 * ClassName: HttpPostUploadUtil
 * @Description: 多媒体上传
 * @author dapengniao
 * @date 2016年3月14日 上午11:56:55
 */
public class HttpPostUploadUtil { 
   
  public String urlStr; 
   
  public HttpPostUploadUtil(){
    urlStr = "http://file.api.weixin.qq.com/cgi-bin/media/upload?access_token="+GlobalConstants.getInterfaceUrl("access_token")+"&type=image"; 
  }
    
    
  
  /** 
   * 上传图片 
   * 
   * @param urlStr 
   * @param textMap 
   * @param fileMap 
   * @return 
   */ 
  @SuppressWarnings("rawtypes")
  public String formUpload(Map<String,String> textMap,Map<String,String> fileMap) { 
    String res = ""; 
    HttpURLConnection conn = null; 
    String BOUNDARY = "---------------------------123821742118716"; //boundary就是request头和上传文件内容的分隔符 
    try { 
      URL url = new URL(urlStr); 
      conn = (HttpURLConnection) url.openConnection(); 
      conn.setConnectTimeout(5000); 
      conn.setReadTimeout(30000); 
      conn.setDoOutput(true); 
      conn.setDoInput(true); 
      conn.setUseCaches(false); 
      conn.setRequestMethod("POST"); 
      conn.setRequestProperty("Connection","Keep-Alive"); 
      conn 
          .setRequestProperty("User-Agent","Mozilla/5.0 (Windows; U; Windows NT 6.1; zh-CN; rv:1.9.2.6)"); 
      conn.setRequestProperty("Content-Type","multipart/form-data; boundary=" + BOUNDARY); 
  
      OutputStream out = new DataOutputStream(conn.getOutputStream()); 
      // text 
      if (textMap != null) { 
        StringBuffer strBuf = new StringBuffer(); 
        Iterator<?> iter = textMap.entrySet().iterator(); 
        while (iter.hasNext()) { 
          Map.Entry entry = (Map.Entry) iter.next(); 
          String inputName = (String) entry.getKey(); 
          String inputValue = (String) entry.getValue(); 
          if (inputValue == null) { 
            continue; 
          } 
          strBuf.append("rn").append("--").append(BOUNDARY).append( 
              "rn"); 
          strBuf.append("Content-Disposition: form-data; name="" 
              + inputName + ""rnrn"); 
          strBuf.append(inputValue); 
        } 
        out.write(strBuf.toString().getBytes()); 
      } 
  
      // file 
      if (fileMap != null) { 
        Iterator<?> iter = fileMap.entrySet().iterator(); 
        while (iter.hasNext()) { 
          Map.Entry entry = (Map.Entry) iter.next(); 
          String inputName = (String) entry.getKey(); 
          String inputValue = (String) entry.getValue(); 
          if (inputValue == null) { 
            continue; 
          } 
          File file = new File(inputValue); 
          String filename = file.getName(); 
          String contentType = new MimetypesFileTypeMap() 
              .getContentType(file); 
          if (filename.endsWith(".jpg")) { 
            contentType = "image/jpg"; 
          } 
          if (contentType == null || contentType.equals("")) { 
            contentType = "application/octet-stream"; 
          } 
  
          StringBuffer strBuf = new StringBuffer(); 
          strBuf.append("rn").append("--").append(BOUNDARY).append( 
              "rn"); 
          strBuf.append("Content-Disposition: form-data; name="" 
              + inputName + ""; filename="" + filename 
              + ""rn"); 
          strBuf.append("Content-Type:" + contentType + "rnrn"); 
  
          out.write(strBuf.toString().getBytes()); 
  
          DataInputStream in = new DataInputStream( 
              new FileInputStream(file)); 
          int bytes = 0; 
          byte[] bufferOut = new byte[1024]; 
          while ((bytes = in.read(bufferOut)) != -1) { 
            out.write(bufferOut,bytes); 
          } 
          in.close(); 
        } 
      } 
  
      byte[] endData = ("rn--" + BOUNDARY + "--rn").getBytes(); 
      out.write(endData); 
      out.flush(); 
      out.close(); 
  
      // 读取返回数据 
      StringBuffer strBuf = new StringBuffer(); 
      BufferedReader reader = new BufferedReader(new InputStreamReader( 
          conn.getInputStream())); 
      String line = null; 
      while ((line = reader.readLine()) != null) { 
        strBuf.append(line).append("n"); 
      } 
      res = strBuf.toString(); 
      reader.close(); 
      reader = null; 
    } catch (Exception e) { 
      System.out.println("发送POST请求出错。" + urlStr); 
      e.printStackTrace(); 
    } finally { 
      if (conn != null) { 
        conn.disconnect(); 
        conn = null; 
      } 
    } 
    return res; 
  } 
  
}

String openid = map.get("FromUserName"); // 用户openid
String mpid = map.get("ToUserName"); // 公众号原始ID
ImageMessage imgmsg = new ImageMessage();
imgmsg.setToUserName(openid);
imgmsg.setFromUserName(mpid);
imgmsg.setCreateTime(new Date().getTime());
imgmsg.setMsgType(MessageUtil.RESP_MESSAGE_TYPE_Image);
if (map.get("Event").equals(MessageUtil.EVENT_TYPE_SUBSCRIBE)) { // 关注事件
  System.out.println("==============这是关注事件！");
  Image img = new Image();
  HttpPostUploadUtil util=new HttpPostUploadUtil();
  String filepath="H:1.jpg"; 
  Map<String,String> textMap = new HashMap<String,String>(); 
  textMap.put("name","testname"); 
  Map<String,String> fileMap = new HashMap<String,String>(); 
  fileMap.put("userfile",filepath); 
  String mediaidrs = util.formUpload(textMap,fileMap);
  System.out.println(mediaidrs);
  String mediaid=JSONObject.fromObject(mediaidrs).getString("media_id");
  img.setMediaId(mediaid);
  imgmsg.setImage(img);
  return MessageUtil.imageMessageToXml(imgmsg);
}