java微信开发之上传下载多媒体文件

将多媒体文件上传到微信服务器，以及从微信服务器下载文件，可以参考：http://mp.weixin.qq.com/wiki/index.php?title=上传下载多媒体文件

上传下载多媒体文件的方法还是写到WeixinUtil.java中。

代码如下：

import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.SecureRandom;
import java.util.Calendar;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
 
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;
 
import net.sf.json.JSONObject;
 
import org.apache.commons.lang.StringUtils;
import org.apache.log4j.Logger;
 
import com.company.project.model.menu.AccessToken;
import com.company.project.model.menu.Menu;
 
public class WeixinUtil {
 private static Logger log = Logger.getLogger(WeixinUtil.class);
 public final static String APPID = "wxb927d4280e6db674";
 public final static String APP_SECRET = "21441e9f3226eee81e14380a768b6d1e";
 // 获取access_token的接口地址（GET） 限200（次/天）
 public final static String access_token_url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=APPID&secret=APPSECRET";
 // 创建菜单
 public final static String create_menu_url = "https://api.weixin.qq.com/cgi-bin/menu/create?access_token=ACCESS_TOKEN";
 // 存放：1.token，2：获取token的时间,3.过期时间
 public final static Map<String,Object> accessTokenMap = new HashMap<String,Object>();
 /**
 * 发起https请求并获取结果
 * 
 * @param requestUrl 请求地址
 * @param requestMethod 请求方式（GET、POST）
 * @param outputStr 提交的数据
 * @return JSONObject(通过JSONObject.get(key)的方式获取json对象的属性值)
 */
 public static JSONObject handleRequest(String requestUrl,String requestMethod,String outputStr) {
 JSONObject jsonObject = null;
  
 try {
  URL url = new URL(requestUrl);
  HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();
  SSLContext ctx = SSLContext.getInstance("SSL", "SunJSSE");
  TrustManager[] tm = {new MyX509TrustManager()};
  ctx.init(null, tm, new SecureRandom());
  SSLSocketFactory sf = ctx.getSocketFactory();
  conn.setSSLSocketFactory(sf);
  conn.setDoInput(true);
  conn.setDoOutput(true);
  conn.setRequestMethod(requestMethod);
  conn.setUseCaches(false);
   
  if ("GET".equalsIgnoreCase(requestMethod)) {
  conn.connect();
  }
   
  if (StringUtils.isNotEmpty(outputStr)) {
  OutputStream out = conn.getOutputStream();
  out.write(outputStr.getBytes("utf-8"));
  out.close();
  }
   
  InputStream in = conn.getInputStream();
  BufferedReader br = new BufferedReader(new InputStreamReader(in,"utf-8"));
  StringBuffer buffer = new StringBuffer();
  String line = null;
   
  while ((line = br.readLine()) != null) {
  buffer.append(line);
  }
   
  in.close();
  conn.disconnect();
   
  jsonObject = JSONObject.fromObject(buffer.toString());
 } catch (MalformedURLException e) {
  e.printStackTrace();
  log.error("URL错误！");
 } catch (IOException e) {
  e.printStackTrace();
 } catch (NoSuchAlgorithmException e) {
  e.printStackTrace();
 } catch (NoSuchProviderException e) {
  e.printStackTrace();
 } catch (KeyManagementException e) {
  e.printStackTrace();
 }
 return jsonObject;
 }
  
 /**
 * 获取access_token
 *
 * @author qincd
 * @date Nov 6, 2014 9:56:43 AM
 */
 public static AccessToken getAccessToken(String appid,String appSecret) {
 AccessToken at = new AccessToken();
 // 每次获取access_token时，先从accessTokenMap获取，如果过期了就重新从微信获取
 // 没有过期直接返回
 // 从微信获取的token的有效期为2个小时
 if (!accessTokenMap.isEmpty()) {
  Date getTokenTime = (Date) accessTokenMap.get("getTokenTime");
  Calendar c = Calendar.getInstance();
  c.setTime(getTokenTime);
  c.add(Calendar.HOUR_OF_DAY, 2);
   
  getTokenTime = c.getTime();
  if (getTokenTime.after(new Date())) {
  log.info("缓存中发现token未过期，直接从缓存中获取access_token");
  // token未过期，直接从缓存获取返回
  String token = (String) accessTokenMap.get("token");
  Integer expire = (Integer) accessTokenMap.get("expire");
  at.setToken(token);
  at.setExpiresIn(expire);
  return at;
  }
 }
 String requestUrl = access_token_url.replace("APPID", appid).replace("APPSECRET", appSecret);
  
 JSONObject object = handleRequest(requestUrl, "GET", null);
 String access_token = object.getString("access_token");
 int expires_in = object.getInt("expires_in");
  
 log.info("\naccess_token:" + access_token);
 log.info("\nexpires_in:" + expires_in);
  
 at.setToken(access_token);
 at.setExpiresIn(expires_in);
  
 // 每次获取access_token后，存入accessTokenMap
 // 下次获取时，如果没有过期直接从accessTokenMap取。
 accessTokenMap.put("getTokenTime", new Date());
 accessTokenMap.put("token", access_token);
 accessTokenMap.put("expire", expires_in);
  
 return at;
 }
  
 /**
 * 创建菜单
 *
 * @author qincd
 * @date Nov 6, 2014 9:56:36 AM
 */
 public static boolean createMenu(Menu menu,String accessToken) {
 String requestUrl = create_menu_url.replace("ACCESS_TOKEN", accessToken);
 String menuJsonString = JSONObject.fromObject(menu).toString();
 JSONObject jsonObject = handleRequest(requestUrl, "POST", menuJsonString);
 String errorCode = jsonObject.getString("errcode");
 if (!"0".equals(errorCode)) {
  log.error(String.format("菜单创建失败！errorCode:%d,errorMsg:%s",jsonObject.getInt("errcode"),jsonObject.getString("errmsg")));
  return false;
 }
  
 log.info("菜单创建成功！");
  
 return true;
 }
  
 // 上传多媒体文件到微信服务器
 public static final String upload_media_url = "http://file.api.weixin.qq.com/cgi-bin/media/upload?access_token=ACCESS_TOKEN&type=TYPE";
 /**
 * 上传多媒体文件到微信服务器<br>
 * @see http://www.oschina.net/code/snippet_1029535_23824
 * @see http://mp.weixin.qq.com/wiki/index.php?title=上传下载多媒体文件
 *
 * @author qincd
 * @date Nov 6, 2014 4:11:22 PM
 */
 public static JSONObject uploadMediaToWX(String filePath,String type,String accessToken) throws IOException{
 File file = new File(filePath);
 if (!file.exists()) {
  log.error("文件不存在！");
  return null;
 }
  
 String url = upload_media_url.replace("ACCESS_TOKEN", accessToken).replace("TYPE", type);
 URL urlObj = new URL(url);
 HttpURLConnection conn = (HttpURLConnection) urlObj.openConnection();
 conn.setDoInput(true);
 conn.setDoOutput(true);
 conn.setUseCaches(false);
  
 conn.setRequestProperty("Connection", "Keep-Alive");
    conn.setRequestProperty("Charset", "UTF-8");
  
    // 设置边界
    String BOUNDARY = "----------" + System.currentTimeMillis();
    conn.setRequestProperty("Content-Type", "multipart/form-data; boundary="
        + BOUNDARY);
  
    // 请求正文信息
  
    // 第一部分：
    StringBuilder sb = new StringBuilder();