Java tutorial
/******* Copyright 2015 NeuroBASE,Inc. All Rights Reserved. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. **********/ package com.echopf; import java.util.*; import java.util.concurrent.Callable; import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; import java.net.*; import java.io.*; import javax.net.ssl.HttpsURLConnection; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import android.os.Handler; /** * The ECHOQuery contains basic query methods used by the SDK. */ public class ECHOQuery { /** * Disable constructor since this is an utility class. */ private ECHOQuery() { } /** * Does Find objects from the remote server. * @param sync : if set TRUE, then the main (UI) thread is waited for complete the finding in a background thread. * (a synchronous communication) * @param listKey the key associated with the object list * @param clazz the object class * @param callback invoked after the finding is completed * @param instanceId the reference ID of the finding target instance * @param resourceType the type of this object * @param params to control the output objects * @throws ECHOException */ public static <T extends ECHODataObject<T>> ECHOList<T> doFind(final boolean sync, final String listKey, final String resourceType, final FindCallback<T> callback, final String instanceId, final JSONObject fParams, final ECHODataObjectFactory<T> factory) throws ECHOException { // Get ready a background thread final Handler handler = new Handler(); ExecutorService executor = Executors.newSingleThreadExecutor(); Callable<ECHOList<T>> communicator = new Callable<ECHOList<T>>() { @Override public ECHOList<T> call() throws ECHOException { ECHOException exception = null; ECHOList<T> objList = null; try { JSONObject response = getRequest(instanceId + "/" + resourceType, fParams); /* begin copying data */ objList = new ECHOList<T>(response.optJSONObject("paginate")); JSONArray items = response.optJSONArray(listKey); if (items == null) throw new ECHOException(0, "Invalid data type for response-field `" + listKey + "`."); for (int i = 0; i < items.length(); i++) { JSONObject item = items.optJSONObject(i); if (item == null) throw new ECHOException(0, "Invalid data type for response-field `" + listKey + "`."); String refid = item.optString("refid"); if (refid.isEmpty()) continue; T obj = factory.create(instanceId, refid, item); objList.add(obj); } /* end copying data */ } catch (ECHOException e) { exception = e; } catch (Exception e) { exception = new ECHOException(e); } if (sync == false) { // Execute a callback method in the main (UI) thread. if (callback != null) { final ECHOException fException = exception; final ECHOList<T> fObjList = objList; handler.post(new Runnable() { @Override public void run() { callback.done(fObjList, fException); } }); } return null; } else { if (exception == null) return objList; throw exception; } } }; Future<ECHOList<T>> future = executor.submit(communicator); if (sync) { try { return future.get(); } catch (InterruptedException e) { Thread.currentThread().interrupt(); // ignore/reset } catch (ExecutionException e) { Throwable e2 = e.getCause(); if (e2 instanceof ECHOException) { throw (ECHOException) e2; } throw new RuntimeException(e2); } } return null; } /** * Sends a GET request. * @param path a request url path * @throws ECHOException */ public static JSONObject getRequest(String path) throws ECHOException { return request(path, "GET"); } /** * Sends a GET request with optional request parameters. * @param path a request url path * @param query optional request parameters * @throws ECHOException */ public static JSONObject getRequest(String path, JSONObject query) throws ECHOException { return request(path, "GET", query); } /** * Sends a POST request. * @param path a request url path * @param data request contents * @throws ECHOException */ public static JSONObject postRequest(String path, JSONObject data) throws ECHOException { return request(path, "POST", data); } /** * Sends a multipart POST request. * @param path a request url path * @param data request contents * @throws ECHOException */ public static JSONObject multipartPostRequest(String path, JSONObject data) throws ECHOException { return request(path, "POST", data, true); } /** * Sends a PUT request. * @param path a request url path * @param data request contents * @throws ECHOException */ public static JSONObject putRequest(String path, JSONObject data) throws ECHOException { return request(path, "PUT", data); } /** * Sends a multipart PUT request. * @param path a request url path * @param data request contents * @throws ECHOException */ public static JSONObject multipartPutRequest(String path, JSONObject data) throws ECHOException { return request(path, "PUT", data, true); } /** * Sends a DELETE request * @param path a request url path * @throws ECHOException */ public static JSONObject deleteRequest(String path) throws ECHOException { return request(path, "DELETE"); } /** * Sends a HTTP request. * @param path a request url path * @param httpMethod a request method (GET/POST/PUT/DELETE) * @throws ECHOException */ public static JSONObject request(String path, String httpMethod) throws ECHOException { return request(path, httpMethod, null); } /** * Sends a HTTP request. * @param path a request url path * @param httpMethod a request method (GET/POST/PUT/DELETE) * @param data request contents/parameters * @throws ECHOException */ public static JSONObject request(String path, String httpMethod, JSONObject data) throws ECHOException { return request(path, httpMethod, data, false); } /** * Sends a HTTP request with optional request contents/parameters. * @param path a request url path * @param httpMethod a request method (GET/POST/PUT/DELETE) * @param data request contents/parameters * @param multipart use multipart/form-data to encode the contents * @throws ECHOException */ public static JSONObject request(String path, String httpMethod, JSONObject data, boolean multipart) throws ECHOException { JSONObject response = null; try { String jsonStr = ECHOQuery.getResponseString(requestRaw(path, httpMethod, data, multipart)); response = new JSONObject(jsonStr); } catch (JSONException e) { throw new ECHOException(ECHOException.INVALID_JSON_FORMAT, "Invalid JSON format."); } return response; } /** * Sends a HTTP request with optional request contents/parameters. * @param path a request url path * @param httpMethod a request method (GET/POST/PUT/DELETE) * @param data request contents/parameters * @param multipart use multipart/form-data to encode the contents * @throws ECHOException */ public static InputStream requestRaw(String path, String httpMethod, JSONObject data, boolean multipart) throws ECHOException { final String secureDomain = ECHO.secureDomain; if (secureDomain == null) throw new IllegalStateException("The SDK is not initialized.Please call `ECHO.initialize()`."); String baseUrl = new StringBuilder("https://").append(secureDomain).toString(); String url = new StringBuilder(baseUrl).append("/").append(path).toString(); HttpsURLConnection httpClient = null; try { URL urlObj = new URL(url); StringBuilder apiUrl = new StringBuilder(baseUrl).append(urlObj.getPath()).append("/rest_api=1.0/"); // Append the QueryString contained in path boolean isContainQuery = urlObj.getQuery() != null; if (isContainQuery) apiUrl.append("?").append(urlObj.getQuery()); // Append the QueryString from data if (httpMethod.equals("GET") && data != null) { boolean firstItem = true; Iterator<?> iter = data.keys(); while (iter.hasNext()) { if (firstItem && !isContainQuery) { firstItem = false; apiUrl.append("?"); } else { apiUrl.append("&"); } String key = (String) iter.next(); String value = data.optString(key); apiUrl.append(key); apiUrl.append("="); apiUrl.append(value); } } URL urlConn = new URL(apiUrl.toString()); httpClient = (HttpsURLConnection) urlConn.openConnection(); } catch (IOException e) { throw new ECHOException(e); } final String appId = ECHO.appId; final String appKey = ECHO.appKey; final String accessToken = ECHO.accessToken; if (appId == null || appKey == null) throw new IllegalStateException("The SDK is not initialized.Please call `ECHO.initialize()`."); InputStream responseInputStream = null; try { httpClient.setRequestMethod(httpMethod); httpClient.addRequestProperty("X-ECHO-APP-ID", appId); httpClient.addRequestProperty("X-ECHO-APP-KEY", appKey); // Set access token if (accessToken != null && !accessToken.isEmpty()) httpClient.addRequestProperty("X-ECHO-ACCESS-TOKEN", accessToken); // Build content if (!httpMethod.equals("GET") && data != null) { httpClient.setDoOutput(true); httpClient.setChunkedStreamingMode(0); // use default chunk size if (multipart == false) { // application/json httpClient.addRequestProperty("CONTENT-TYPE", "application/json"); BufferedWriter wrBuffer = new BufferedWriter( new OutputStreamWriter(httpClient.getOutputStream())); wrBuffer.write(data.toString()); wrBuffer.close(); } else { // multipart/form-data final String boundary = "*****" + UUID.randomUUID().toString() + "*****"; final String twoHyphens = "--"; final String lineEnd = "\r\n"; final int maxBufferSize = 1024 * 1024 * 3; httpClient.setRequestMethod("POST"); httpClient.addRequestProperty("CONTENT-TYPE", "multipart/form-data; boundary=" + boundary); final DataOutputStream outputStream = new DataOutputStream(httpClient.getOutputStream()); try { JSONObject postData = new JSONObject(); postData.putOpt("method", httpMethod); postData.putOpt("data", data); new Object() { public void post(JSONObject data, List<String> currentKeys) throws JSONException, IOException { Iterator<?> keys = data.keys(); while (keys.hasNext()) { String key = (String) keys.next(); List<String> newKeys = new ArrayList<String>(currentKeys); newKeys.add(key); Object val = data.get(key); // convert JSONArray into JSONObject if (val instanceof JSONArray) { JSONArray array = (JSONArray) val; JSONObject val2 = new JSONObject(); for (Integer i = 0; i < array.length(); i++) { val2.putOpt(i.toString(), array.get(i)); } val = val2; } // build form-data name String name = ""; for (int i = 0; i < newKeys.size(); i++) { String key2 = newKeys.get(i); name += (i == 0) ? key2 : "[" + key2 + "]"; } if (val instanceof ECHOFile) { ECHOFile file = (ECHOFile) val; if (file.getLocalBytes() == null) continue; InputStream fileInputStream = new ByteArrayInputStream( file.getLocalBytes()); if (fileInputStream != null) { String mimeType = URLConnection .guessContentTypeFromName(file.getFileName()); // write header outputStream.writeBytes(twoHyphens + boundary + lineEnd); outputStream.writeBytes("Content-Disposition: form-data; name=\"" + name + "\"; filename=\"" + file.getFileName() + "\"" + lineEnd); outputStream.writeBytes("Content-Type: " + mimeType + lineEnd); outputStream.writeBytes("Content-Transfer-Encoding: binary" + lineEnd); outputStream.writeBytes(lineEnd); // write content int bytesAvailable, bufferSize, bytesRead; do { bytesAvailable = fileInputStream.available(); bufferSize = Math.min(bytesAvailable, maxBufferSize); byte[] buffer = new byte[bufferSize]; bytesRead = fileInputStream.read(buffer, 0, bufferSize); if (bytesRead <= 0) break; outputStream.write(buffer, 0, bufferSize); } while (true); fileInputStream.close(); outputStream.writeBytes(lineEnd); } } else if (val instanceof JSONObject) { this.post((JSONObject) val, newKeys); } else { String data2 = null; try { // in case of boolean boolean bool = data.getBoolean(key); data2 = bool ? "true" : ""; } catch (JSONException e) { // if the value is not a Boolean or the String "true" or "false". data2 = val.toString().trim(); } // write header outputStream.writeBytes(twoHyphens + boundary + lineEnd); outputStream.writeBytes( "Content-Disposition: form-data; name=\"" + name + "\"" + lineEnd); outputStream .writeBytes("Content-Type: text/plain; charset=UTF-8" + lineEnd); outputStream.writeBytes("Content-Length: " + data2.length() + lineEnd); outputStream.writeBytes(lineEnd); // write content byte[] bytes = data2.getBytes(); for (int i = 0; i < bytes.length; i++) { outputStream.writeByte(bytes[i]); } outputStream.writeBytes(lineEnd); } } } }.post(postData, new ArrayList<String>()); } catch (JSONException e) { throw new ECHOException(e); } finally { outputStream.writeBytes(twoHyphens + boundary + lineEnd); outputStream.flush(); outputStream.close(); } } } else { httpClient.addRequestProperty("CONTENT-TYPE", "application/json"); } if (httpClient.getResponseCode() != -1 /*== HttpURLConnection.HTTP_OK*/) { responseInputStream = httpClient.getInputStream(); } } catch (IOException e) { // get http response code int errorCode = -1; try { errorCode = httpClient.getResponseCode(); } catch (IOException e1) { throw new ECHOException(e1); } // get error contents JSONObject responseObj; try { String jsonStr = ECHOQuery.getResponseString(httpClient.getErrorStream()); responseObj = new JSONObject(jsonStr); } catch (JSONException e1) { if (errorCode == 404) { throw new ECHOException(ECHOException.RESOURCE_NOT_FOUND, "Resource not found."); } throw new ECHOException(ECHOException.INVALID_JSON_FORMAT, "Invalid JSON format."); } // if (responseObj != null) { int code = responseObj.optInt("error_code"); String message = responseObj.optString("error_message"); if (code != 0 || !message.equals("")) { JSONObject details = responseObj.optJSONObject("error_details"); if (details == null) { throw new ECHOException(code, message); } else { throw new ECHOException(code, message, details); } } } throw new ECHOException(e); } return responseInputStream; } /** * Converts a response input stream into string. */ private static String getResponseString(InputStream inputStream) { try { if (inputStream != null) { BufferedReader rdBuffer = new BufferedReader(new InputStreamReader(inputStream)); StringBuilder ret = new StringBuilder(); String str = null; while ((str = rdBuffer.readLine()) != null) { ret.append(str); } rdBuffer.close(); return ret.toString(); } } catch (IOException e) { throw new RuntimeException(e); } return null; } }