微信公众平台开发（5）-上传下载多媒体文件

小灰灰 2022-08-13 16:38 218阅读 0赞

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;
    	}
    }