Google Drive REST API V3 > Root listing > Google Drive REST API V3 Getting Root Folder Id > List of Files & Folders From Root Directory

My target to listing all files of 'My Drive', but only the files and folders which are immediately below, not all the ones in the Drive at once. It's easy with REST API V3, below is a full code snippet to get listing of files and folders from ROOT FOLDER

package com.pkm; import java.io.*; import java.net.URL; import java.net.URLEncoder; import java.nio.charset.Charset; import java.nio.file.Files; import java.util.HashMap; import java.util.List; import java.util.Map; import sun.misc.BASE64Encoder; import com.google.gson.Gson; import javax.net.ssl.HttpsURLConnection; import javax.net.ssl.SSLContext; /** * Created by [PRITOM KUMAR] on 05-Oct-18. */ public class GoogleDriveRestApiV3 { public static void main(String[] args) throws Exception { /* I assumed you already have ACCESS TOKEN */ String AUTH_TOKEN = "ya29.GlwtBm__"; String FIELDS = "nextPageToken,files(id,name,mimeType,trashed,size,quotaBytesUsed)"; String QUERY = URLEncoder.encode( "'root' in parents " + "and trashed = false", "UTF-8" ); String URI = "https://www.googleapis.com/drive/v3/files?" + "fields=" + FIELDS + "&q=" + QUERY + "&access_token=" + AUTH_TOKEN; Map result = HttpJavaClient.doGet(URI); System.out.println(result); File outputFile = (File) result.get("outputFile"); if (outputFile != null) { String output = ""; List<String> lines = Files.readAllLines(outputFile.toPath(), Charset.defaultCharset()); for (String line : lines) { output = output + line; } Gson gson = new Gson(); Map data = gson.fromJson(output, Map.class); System.out.println(data); List<Map> files = (List<Map>) data.get("files"); for (Map map : files) { System.out.println(map); } } } public static String base64Encode(byte[] data) { BASE64Encoder base64Encoder = new BASE64Encoder(); return base64Encoder.encodeBuffer(data); } } class HttpJavaClient { public static enum Method { GET, POST, PUT, PATCH, DELETE } public static enum Type { XML, JSON, URL_ENCODED, HTTP; } public static Map doGet(String url) { return execute(url, Method.GET, "", Type.URL_ENCODED, null, null); } public static Map doPost(String url, String data, Type type, Map headers) { return execute(url, Method.POST, data, type, headers, null); } private static Map execute(String requestURL, Method requestMethod, String requestData, Type dataType, Map headers, Integer timeOutMilli) { String httpResponse = "", responseMessage = ""; Integer httpCode = 0; timeOutMilli = timeOutMilli == null ? 1000 * 30 : timeOutMilli; /* Default read & write timeout */ Map r = new HashMap(); HttpsURLConnection connection = null; try { String contentType = "", accept = "", contentLength = "" + requestData.length(); switch (dataType) { case XML: contentType = "text/xml; charset=utf-8"; accept = "text/xml"; break; case JSON: contentType = "application/json"; break; case URL_ENCODED: contentType = "application/x-www-form-urlencoded"; break; } connection = (HttpsURLConnection) new URL(requestURL).openConnection(); connection.setRequestMethod(requestMethod.name()); connection.setConnectTimeout(timeOutMilli); connection.setReadTimeout(timeOutMilli); connection.setRequestProperty("Pragma", "no-cache"); if (headers != null && headers.size() > 0) { for (Object name : headers.keySet().toArray()) { if (name.toString().endsWith("tls")) { //headers.put("tls", "TLSv1.2"); //headers.put("tls", "TLSv1"); SSLContext sc = SSLContext.getInstance(headers.get(name.toString()).toString()); sc.init(null, null, new java.security.SecureRandom()); connection.setSSLSocketFactory(sc.getSocketFactory()); } else { connection.setRequestProperty(name.toString(), headers.get(name.toString()).toString()); } } } if (requestData.length() > 0) { connection.setDoInput(true); connection.setDoOutput(true); if (accept.length() > 0) { connection.setRequestProperty("Accept", accept); } if (contentType.length() > 0) { connection.setRequestProperty("Content-Type", contentType); } connection.setRequestProperty("Content_length", contentLength); OutputStreamWriter writer = new OutputStreamWriter(connection.getOutputStream(), "UTF-8"); writer.write(requestData); writer.flush(); writer.close(); } httpCode = connection.getResponseCode(); responseMessage = connection.getResponseMessage(); if (httpCode >= 200 && httpCode <= 299) { String responseContentType = connection.getContentType(); if (responseContentType == null || responseContentType.length() == 0) { responseContentType = "txt"; } else { if (responseContentType.contains(";")) { responseContentType = responseContentType.substring(0, responseContentType.indexOf(";")); } if (responseContentType.contains("text/html")) { responseContentType = "html"; } else if (responseContentType.contains("image/")) { responseContentType = "image"; } else if (responseContentType.contains("/")) { String[] parts = responseContentType.split("/"); responseContentType = parts[parts.length - 1]; } } Map<String, List<String>> map = connection.getHeaderFields(); for (Map.Entry<String, List<String>> entry : map.entrySet()) { System.out.println("Key=" + entry.getKey() + " ,Value=" + entry.getValue()); } System.out.println("Key=ResponseType ,Value=" + responseContentType); File tempFile = File.createTempFile("hello", ".tmp"); RandomAccessFile output = new RandomAccessFile(tempFile, "rw"); InputStream is = connection.getInputStream(); BufferedInputStream input = new BufferedInputStream(is); Integer fileLength = connection.getContentLength(); int readSize = 1024, downloadedSize = 0; byte data[] = new byte[readSize]; int count = 0; int progress = 0; Long timeNeeded = System.currentTimeMillis(); while ((count = input.read(data, 0, readSize)) >= 0 && progress != 100) { downloadedSize += count; output.write(data, 0, count); progress = (int) ((downloadedSize * 100) / fileLength); Long mb = output.length() / (1024 * 1024); System.out.println("PROGRESS = " + (progress) + "%, DOWNLOADED=" + mb + " MB, TYPE=" + responseContentType); } output.close(); input.close(); r.put("outputFile", tempFile); timeNeeded = (System.currentTimeMillis() - timeNeeded) / 1000; System.out.println("TIME REQUIRED=" + timeNeeded + " SECONDS!!!"); } } catch (Exception ex) { httpResponse = ""; responseMessage = ex.getMessage(); } finally { try { connection.disconnect(); } catch (Exception ex10) { } } r.put("code", httpCode); r.put("message", responseMessage); r.put("output", httpResponse); return r; } }

Below is output of above example:

Key=null ,Value=[HTTP/1.1 200 OK] Key=X-Frame-Options ,Value=[SAMEORIGIN] Key=Alt-Svc ,Value=[quic=":443"; ma=2592000; v="44,43,39,35"] Key=Vary ,Value=[X-Origin, Origin] Key=Date ,Value=[Fri, 05 Oct 2018 12:26:57 GMT] Key=Content-Length ,Value=[737] Key=X-XSS-Protection ,Value=[1; mode=block] Key=Expires ,Value=[Fri, 05 Oct 2018 12:26:57 GMT] Key=Content-Type ,Value=[application/json; charset=UTF-8] Key=Server ,Value=[GSE] Key=X-Content-Type-Options ,Value=[nosniff] Key=Cache-Control ,Value=[private, max-age=0, must-revalidate, no-transform] Key=ResponseType ,Value=json PROGRESS = 100%, DOWNLOADED=0 MB, TYPE=json TIME REQUIRED=0 SECONDS!!! {message=OK, outputFile=C:\Users\HP\AppData\Local\Temp\hello8652555977765600581.tmp, code=200, output=} {files=[{id=1KRehy6fX-6WwWi4AAERUklXki8EqwoWh, name=Mine.txt, mimeType=text/plain, trashed=false, size=7, quotaBytesUsed=7}, {id=12EC7CqD4gY3w9SGefvpO_VQQubWGZ_Vb, name=CORE-ITEMS, mimeType=application/vnd.google-apps.folder, trashed=false, quotaBytesUsed=0}, {id=1rGwUE6XV2hfmv0NamUI-sfpdSSERdZ0j, name=[RePack] Full Version Game.zip, mimeType=application/x-zip-compressed, trashed=false, size=4832867859, quotaBytesUsed=4832867859}]} {id=1KRehy6fX-6WwWi4AAERUklXki8EqwoWh, name=Mine.txt, mimeType=text/plain, trashed=false, size=7, quotaBytesUsed=7} {id=12EC7CqD4gY3w9SGefvpO_VQQubWGZ_Vb, name=CORE-ITEMS, mimeType=application/vnd.google-apps.folder, trashed=false, quotaBytesUsed=0} {id=1rGwUE6XV2hfmv0NamUI-sfpdSSERdZ0j, name=[RePack] Full Version Game.zip, mimeType=application/x-zip-compressed, trashed=false, size=4832867859, quotaBytesUsed=4832867859}