微信公众平台开发（5）-上传下载多媒体文件

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/qincidong/article/details/40864167

回复图片、音频、视频消息都是需要media_id的，这个是需要将多媒体文件上传到微信服务器才有的。

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();
        sb.append("--"); // ////////必须多两道线
        sb.append(BOUNDARY);
        sb.append("\r\n");
        sb.append("Content-Disposition: form-data;name=\"file\";filename=\""
                + file.getName() + "\"\r\n");
        sb.append("Content-Type:application/octet-stream\r\n\r\n");
 
        byte[] head = sb.toString().getBytes("utf-8");
 
        // 获得输出流
        OutputStream out = new DataOutputStream(conn.getOutputStream());
        out.write(head);
 
        // 文件正文部分
        DataInputStream in = new DataInputStream(new FileInputStream(file));
        int bytes = 0;
        byte[] bufferOut = new byte[1024];
        while ((bytes = in.read(bufferOut)) != -1) {
            out.write(bufferOut, 0, bytes);
        }
        in.close();
 
        // 结尾部分
        byte[] foot = ("\r\n--" + BOUNDARY + "--\r\n").getBytes("utf-8");// 定义最后数据分隔线
 
        out.write(foot);
 
        out.flush();
        out.close();
 
        /**
         * 读取服务器响应，必须读取,否则提交不成功
         */
         try {
	         // 定义BufferedReader输入流来读取URL的响应
        	 StringBuffer buffer = new StringBuffer();
	         BufferedReader reader = new BufferedReader(new InputStreamReader(
	         conn.getInputStream()));
	         String line = null;
	         while ((line = reader.readLine()) != null) {
	        	 buffer.append(line);
	         }
	         
	         reader.close();
	         conn.disconnect();
	         
	         return JSONObject.fromObject(buffer.toString());
         } catch (Exception e) {
	         log.error("发送POST请求出现异常！" + e);
	         e.printStackTrace();
         }
		return null;
	}
	
	public static final String download_media_url = "http://file.api.weixin.qq.com/cgi-bin/media/get?access_token=ACCESS_TOKEN&media_id=MEDIA_ID";
	/**
	 * 从微信服务器下载多媒体文件
	 *
	 * @author qincd
	 * @date Nov 6, 2014 4:32:12 PM
	 */
	public static String downloadMediaFromWx(String accessToken,String mediaId,String fileSavePath) throws IOException {
		if (StringUtils.isEmpty(accessToken) || StringUtils.isEmpty(mediaId)) return null;
		
		String requestUrl = download_media_url.replace("ACCESS_TOKEN", accessToken).replace("MEDIA_ID", mediaId);
		URL url = new URL(requestUrl);
		HttpURLConnection conn = (HttpURLConnection) url.openConnection();
		conn.setRequestMethod("GET");
		conn.setDoInput(true);
		conn.setDoOutput(true);
		InputStream in = conn.getInputStream();
		
		File dir = new File(fileSavePath);
		if (!dir.exists()) {
			dir.mkdirs();
		}
		if (!fileSavePath.endsWith("/")) {
			fileSavePath += "/";
		}
		
		String ContentDisposition = conn.getHeaderField("Content-disposition");
		String weixinServerFileName = ContentDisposition.substring(ContentDisposition.indexOf("filename")+10, ContentDisposition.length() -1);
		fileSavePath += weixinServerFileName; 
		BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(fileSavePath));
		byte[] data = new byte[1024];
		int len = -1;
		
		while ((len = in.read(data)) != -1) {
			bos.write(data,0,len);
		}
		
		bos.close();
		in.close();
		conn.disconnect();
		
		return fileSavePath;
	}
}

测试代码：

public class WeixinUtilTest {

	/**
	 *
	 * @author qincd
	 * @date Nov 6, 2014 9:57:54 AM
	 */
	public static void main(String[] args) {
		// 1).获取access_token
		AccessToken accessToken = WeixinUtil.getAccessToken(WeixinUtil.APPID, WeixinUtil.APP_SECRET);
		String filePath = "C:\\Users\\qince\\Pictures\\壁纸20141029091612.jpg";
		JSONObject uploadJsonObj = testUploadMedia(filePath,"image",accessToken.getToken());
		if (uploadJsonObj == null) {
			System.out.println("上传图片失败");
			return;
		}
		
		int errcode = 0;
		if (uploadJsonObj.containsKey("errcode")) {
			errcode = uploadJsonObj.getInt("errcode");
		}
		if (errcode == 0) {
			System.out.println("图片上传成功");
			
			String mediaId = uploadJsonObj.getString("media_id");
			long createAt = uploadJsonObj.getLong("created_at");
			System.out.println("--Details:");
			System.out.println("media_id:" + mediaId);
			System.out.println("created_at:" + createAt);
		}
		else {
			System.out.println("图片上传失败！");
			
			String errmsg = uploadJsonObj.getString("errmsg");
			System.out.println("--Details:");
			System.out.println("errcode:" + errcode);
			System.out.println("errmsg:" + errmsg);
		}
		
		String mediaId = "6W-UvSrQ2hkdSdVQJJXShwtFDPLfbGI1qnbNFy8weZyb9Jac2xxxcAUwt8p4sYPH";
		String filepath = testDownloadMedia(accessToken.getToken(), mediaId, "d:/test");
		System.out.println(filepath);
	}


	/**
	 * 上传多媒体文件到微信
	 *
	 * @author qincd
	 * @date Nov 6, 2014 4:15:14 PM
	 */
	public static JSONObject testUploadMedia(String filePath,String type,String accessToken) {
		try {
			return WeixinUtil.uploadMediaToWX(filePath, type, accessToken);
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		return null;
	}
	
	/**
	 * 从微信下载多媒体文件
	 *
	 * @author qincd
	 * @date Nov 6, 2014 4:56:25 PM
	 */
	public static String testDownloadMedia(String accessToken,String mediaId,String fileSaveDir) {
		try {
			return WeixinUtil.downloadMediaFromWx(accessToken, mediaId, fileSaveDir);
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		return null;
	}
}