Java code to Download files using sharepoint APIs

//DOWNLOAD
            try {
		String accessTokenInt = getSharepointToken();
		String accessTokenIntglobal=accessTokenInt;
		System.out.println("Access Token Generated - "+accessTokenIntglobal);
		//Below folderUrl is the directory from where we will download the file. 
		//and SiteURL is organizations' site for e.g. gotobo.sharepoint.com/sites/mysite
		String folderUrl = "Shared%20Documents"+"/test";
		String siteURL = "https://gotobo.sharepoint.com/sites/mysite";
		// ======================================================================
		// Get Folder Names from share point site to match our required directory from where download operation will be performed
		// ======================================================================
		String fUrl0 = siteURL + "/_api/web/GetFolderByServerRelativeUrl(\'" + folderUrl+"/"
				+ "\')/Folders?$orderby=ListItemAllFields/Modified%20desc&$top=1";                            
		URL fileLstUrl0 = new URL(fUrl0);
		URLConnection fConnection0 = fileLstUrl0.openConnection();
		HttpURLConnection httpFConn0 = (HttpURLConnection) fConnection0;
		httpFConn0.setRequestMethod("GET");
		httpFConn0.setRequestProperty("Authorization", "Bearer " + accessTokenIntglobal);
		httpFConn0.setRequestProperty("accept", "application/json;odata=verbose");
		String httpFResponseStr0 = "";
		InputStreamReader fisr0 = null;
		if (httpFConn0.getResponseCode() == 200) {
			fisr0 = new InputStreamReader(httpFConn0.getInputStream());
		} else {
			fisr0 = new InputStreamReader(httpFConn0.getErrorStream());
		}
		BufferedReader fin0 = new BufferedReader(fisr0);
		String strfLine0 = "";
		while ((strfLine0 = fin0.readLine()) != null) {
			httpFResponseStr0 = httpFResponseStr0 + strfLine0;
			System.out.println("strfLine==" + strfLine);
		}
		System.out.println(httpFResponseStr0); // Print
		String fileName0 = "";
		JsonParser fparser0 = new JsonParser();
		JsonObject rootfObj0 = fparser0.parse(httpFResponseStr0).getAsJsonObject();
		JsonArray nameFileArray0 = rootfObj0.get("d").getAsJsonObject().get("results")
				.getAsJsonArray();
		for (JsonElement fpa : nameFileArray0) {
			JsonObject jsonFileNameObj = fpa.getAsJsonObject();
			fileName0 = jsonFileNameObj.get("Name").getAsString();
		}
		System.out.println(fileName0); // Print                         
		// ======================================================================
		// Get File Names to find our file to be downloaded
		// ======================================================================
		String fUrl = siteURL + "/_api/web/GetFolderByServerRelativeUrl(\'" + folderUrl+"/"
				 + "\')/Files?$orderby=ListItemAllFields/Modified%20desc";
		URL fileLstUrl = new URL(fUrl);
		URLConnection fConnection = fileLstUrl.openConnection();
		HttpURLConnection httpFConn = (HttpURLConnection) fConnection;
		httpFConn.setRequestMethod("GET");
		httpFConn.setRequestProperty("Authorization", "Bearer " + accessTokenIntglobal);
		httpFConn.setRequestProperty("accept", "application/json;odata=verbose");
		// Read the response
		String httpFResponseStr = "";
		InputStreamReader fisr = null;
		if (httpFConn.getResponseCode() == 200) {
			fisr = new InputStreamReader(httpFConn.getInputStream());
		} else {
			fisr = new InputStreamReader(httpFConn.getErrorStream());
		}
		BufferedReader fin = new BufferedReader(fisr);
		String strfLine = "";
		while ((strfLine = fin.readLine()) != null) {
			httpFResponseStr = httpFResponseStr + strfLine;
			System.out.println("strfLine==" + strfLine);
		}
		System.out.println(httpFResponseStr); // Print
		// response
		String fileName = "";
		JsonParser fparser = new JsonParser();
		JsonObject rootfObj = fparser.parse(httpFResponseStr).getAsJsonObject();
		JsonArray nameFileArray = rootfObj.get("d").getAsJsonObject().get("results")
				.getAsJsonArray();
		for (JsonElement fpa : nameFileArray) {
			JsonObject jsonFileNameObj = fpa.getAsJsonObject();
			fileName = jsonFileNameObj.get("Name").getAsString();
			//System.out.println("fileName :" + fileName);
			// ======================================================================
			// Download files in the
			// respective
			// folders
			// ======================================================================
			if(fileName.toString().toLowerCase().contains("gotobo.zip"))
			{
			fileName = fileName.replaceAll("\\s", "%20");
			String fileUrl = siteURL + "/_api/web/GetFolderByServerRelativeUrl(\'"
					+ folderUrl + "/" 
					+ "\')/Files('" + fileName + "')/$value";
			URL urlf = new URL(fileUrl);
			URLConnection fconnection = urlf.openConnection();
			HttpURLConnection httpfConn = (HttpURLConnection) fconnection;
			httpfConn.setRequestMethod("GET");
			httpfConn.setRequestProperty("Authorization", "Bearer " + accessTokenIntglobal);
			InputStream inputStream = httpfConn.getInputStream();
			String fileDir = "c:\\users\\gotobo\\";
			//System.out.println("My path : " + fileDir);
			File fileDirs = new File(fileDir);
			if (!fileDirs.exists()) {
				fileDirs.mkdirs();
			}
			fileName = fileName.replaceAll("%20", " ");
			String saveFilePath = "c:\\users\\gotobo\\"+fileName;;
			//System.out.println("saveFilePath.." + saveFilePath);
			FileOutputStream outputStream = new FileOutputStream(saveFilePath);
			int bytesRead = -1;
			byte[] buffer = new byte[1024];
			while ((bytesRead = inputStream.read(buffer)) != -1) {
				outputStream.write(buffer, 0, bytesRead);
			}

			outputStream.close();
			inputStream.close();

			System.out.println(fileName + "  downloaded :");
			if(fileName.length()==0)
			{
				filelink="File not found";
			}
			else
			{
				filelink= "file is found";
			}
		}
		}


        }
        catch (Exception e) {
            e.printStackTrace();
            System.out.println("The file could not be downloaded/Token error/File IO : "+new Timestamp(System.currentTimeMillis()));
            filelink="File not found";
        }