android自更新时下载出现的问题 博客分类： Java 下载downloadHttpStatusandroid 下载

之前做过一个电视台app,电视台app每次启动时会访问服务器,判断是否需要下载新版本

但是下载时老是下载失败,apk包总是下载不下来.到底是什么原因呢?

服务器下载接口如下:

/***
	 * 下载apk
	 * @param path
	 * @param request
	 * @return
	 * @throws IOException
	 */
	@RequestMapping(value = "/download"/*, headers = {"content-type=application/json"}*/)
    public ResponseEntity<byte[]> download( String path,HttpServletRequest request) throws IOException {
    	AccessLog accessLog=logInto(request);
		accessLog.setDescription("下载客户端");
    	if(!ValueWidget.isNullOrEmpty(request.getContentType())&& request.getContentType().toLowerCase().contains("application/json")){
	    	String requestStr=WebServletUtil.getRequestQueryStr(request, null);
	    	System.out.println(requestStr);
	    	Map queryMap=JSONPUtil.getMapFromJson(requestStr);
	    	if(!ValueWidget.isNullOrEmpty(queryMap)){
	    		path=(String) queryMap.get("path");
	    	}
    	}
    	if(ValueWidget.isNullOrEmpty(path)){
    		System.out.println("download failed");
    		accessLog.setOperateResult("下载失败,没有传递path参数");
    		logSave(accessLog, request);
    		return null;
    	}
    	String realpath =WebServletUtil.getUploadPath(request, "upload/download/apk", request
				.getSession().getServletContext(), Constant2.SRC_MAIN_WEBAPP);
    	if(!realpath.endsWith(File.separator)){
    		realpath=realpath+File.separator;
    	}
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
        String fullpath=realpath+path;
        
        System.out.println("download path:"+fullpath);
        headers.set(Constant2.CONTENT_DISPOSITION,WebServletUtil.getContentDisposition(true, path));
        accessLog.setOperateResult("下载成功,下载文件:"+fullpath+" ,size:"+FileUtils.getFileSize2(fullpath));
		logSave(accessLog, request);
        return new ResponseEntity<byte[]>(FileUtils.getBytes4File(fullpath),
                                          headers, HttpStatus.CREATED);
    }

 

安卓端调用的下载方法(核心代码)如下:

/***
	 * 
	 * @param huc
	 * @param sendBytes
	 * @param mode
	 * @param isWrite2file
	 *            : 是否写入文件
	 * @return
	 * @throws Exception
	 */
	private static byte[] connection(HttpURLConnection huc,
			boolean isWrite2file, Object file, String sizeHeadKey)
			throws Exception {
		int resCode = huc.getResponseCode();

		if (resCode == HttpURLConnection.HTTP_OK) {
			int contentLength = 0;
			if (ValueWidget.isNullOrEmpty(sizeHeadKey)) {// 若header中没有size
				contentLength = huc.getContentLength();
			} else {
				String sizeHeaderValue = huc.getHeaderField(sizeHeadKey);
				if (!ValueWidget.isNullOrEmpty(sizeHeaderValue)) {
					contentLength = Integer.parseInt(sizeHeaderValue);
				}

			}
			if (isDetail) {
				System.out
						.println("[connection]contentLength:" + contentLength);
				responseHeaderFields = huc.getHeaderFields();
				String downloadHeader = "Content-Disposition";
				if (!ValueWidget.isNullOrEmpty(responseHeaderFields)) {
					List<String> ContentDispositions = responseHeaderFields
							.get(downloadHeader);
					if (!ValueWidget.isNullOrEmpty(ContentDispositions)) {
						String ContentDisposition = ContentDispositions.get(0);
						System.out.println("ContentDisposition:"
								+ ContentDisposition);
						System.out.println("ContentDisposition convertISO2UTF:"
								+ SystemHWUtil
										.convertISO2UTF(ContentDisposition));
						System.out
								.println("ContentDisposition convertISO2GBK: "
										+ SystemHWUtil
												.convertISO2GBK(ContentDisposition));
					}
				}
				for (Object obj : responseHeaderFields.keySet()) {
					List<String> list = responseHeaderFields.get(obj);
					if (!ValueWidget.isNullOrEmpty(list)) {
						System.out.println(obj + " : "
								+ SystemHWUtil.formatArr(list, ";"));
					}
				}
				System.out
						.println("[connection]contentLength:" + contentLength);
			}
			if (contentLength > 0) {
				if (isDetail)
					System.out
							.println("[HttpSocketUtil.connection]httputil,contentLength:"
									+ contentLength);
				// return readData(huc);
				File file2 = null;
				if (isWrite2file) {
					if (file instanceof File) {
						file2 = (File) file;
						writeFileFromLength(huc, contentLength, file2);
						if (isDetail) {
							System.out.println("download success:"
									+ file2.getAbsolutePath());
						}
					} else {
						writeFileFromLength(huc, contentLength,
								(OutputStream) file);
					}
					return null;
				} else {
					return readDataFromLength(huc, contentLength);
				}
			} else {
				if (isWrite2file) {
					InputStream in = huc.getInputStream();
					FileUtils.writeIn2OutputCloseAll(in, new FileOutputStream(
							(File) file));
					if (isDetail) {
						System.out.println("download success:"
								+ ((File) file).getAbsolutePath());
					}
					return null;
				}
				return readData(huc);
			}
		} else {
			System.out.println("response Code:" + resCode);
		}
		return null;
	}

 

代码本身是没有逻辑错误的.花了很长时间才找到原因,是定义的response的status code不一致.

 

 

后台设置的status code是201,而android端判断的status code是200,不一致导致下载流程没有走到下载逻辑.

修改方法:把后台的status code改为200 就OK了