Java tutorial
/* * Copyright 2014, The gwtquery team. * * 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.cgxlib.xq.client.plugins.deferred; /* * #%L * CGXlib * %% * Copyright (C) 2016 CGXlib (http://www.cgxlib.com) * %% * 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. * #L% Code is originally from gwtquery, and modified by CGXlib team. */ /* * Copyright 2013, The gwtquery team. * * 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. */ import com.cgxlib.xq.client.Function; import com.cgxlib.xq.client.IsProperties; import com.cgxlib.xq.client.js.JsCache; import com.cgxlib.xq.client.js.JsUtils; import com.cgxlib.xq.client.plugins.ajax.Ajax.Settings; import com.cgxlib.xq.client.plugins.deferred.Deferred.DeferredPromiseImpl; import com.google.gwt.core.client.JavaScriptException; import com.google.gwt.core.client.JavaScriptObject; import com.google.gwt.http.client.*; import com.google.gwt.xhr.client.ReadyStateChangeHandler; import com.google.gwt.xhr.client.XMLHttpRequest; /** * Utility class used to create promises for RequestBuilder. * <pre> * RequestBuilder builder = new RequestBuilder(RequestBuilder.GET, "http://127.0.0.1:8888/whatever"); * PromiseRequest gettingResponse = new PromiseReqBuilder(builder); * * gettingResponse.fail(new Function() { * public void f() { * Throwable exception = arguments(0); * } * }).done(new Function() { * public void f() { * Response response = arguments(0); * } * }); * </pre> */ public class PromiseReqBuilder extends DeferredPromiseImpl implements RequestCallback { public PromiseReqBuilder(RequestBuilder builder) { builder.setCallback(this); try { builder.send(); } catch (RequestException e) { onError(null, e); } } /** * Using this constructor we access to some things in the xmlHttpRequest * which are not available in GWT, like adding progress handles or sending * javascript data (like forms in modern html5 file api). */ public PromiseReqBuilder(Settings settings) { String httpMethod = settings.getType(); String url = settings.getUrl(); IsProperties data = settings.getData(); String ctype = settings.getContentType(); Boolean isFormData = data != null && data.getDataImpl() instanceof JavaScriptObject && JsUtils.isFormData(data.<JavaScriptObject>getDataImpl()); XMLHttpRequest xmlHttpRequest = XMLHttpRequest.create(); try { if (settings.getUsername() != null && settings.getPassword() != null) { xmlHttpRequest.open(httpMethod, url, settings.getUsername(), settings.getPassword()); } else if (settings.getUsername() != null) { xmlHttpRequest.open(httpMethod, url, settings.getUsername()); } else { xmlHttpRequest.open(httpMethod, url); } } catch (JavaScriptException e) { RequestPermissionException requestPermissionException = new RequestPermissionException(url); requestPermissionException.initCause(new RequestException(e.getMessage())); onError(null, e); return; } JsUtils.prop(xmlHttpRequest, "onprogress", JsUtils.wrapFunction(new Function() { public void f() { JsCache p = arguments(0); double total = p.getDouble("total"); double loaded = p.getDouble("loaded"); double percent = loaded == 0 ? 0 : total == 0 ? 100 : (100 * loaded / total); dfd.notify(total, loaded, percent, "download"); } })); JavaScriptObject upload = JsUtils.prop(xmlHttpRequest, "upload"); JsUtils.prop(upload, "onprogress", JsUtils.wrapFunction(new Function() { public void f() { JsCache p = arguments(0); double total = p.getDouble("total"); double loaded = p.getDouble("loaded"); double percent = 100 * loaded / total; dfd.notify(total, loaded, percent, "upload"); } })); IsProperties headers = settings.getHeaders(); if (headers != null) { for (String headerKey : headers.getFieldNames()) { xmlHttpRequest.setRequestHeader(headerKey, String.valueOf(headers.get(headerKey))); } } if (data != null && !isFormData && !"GET".equalsIgnoreCase(httpMethod)) { xmlHttpRequest.setRequestHeader("Content-Type", ctype); } // Using xq to set credentials since this method was added in 2.5.1 // xmlHttpRequest.setWithCredentials(true); JsUtils.prop(xmlHttpRequest, "withCredentials", settings.getWithCredentials()); final Request request = createRequestVltr(xmlHttpRequest, settings.getTimeout(), this); xmlHttpRequest.setOnReadyStateChange(new ReadyStateChangeHandler() { public void onReadyStateChange(XMLHttpRequest xhr) { if (xhr.getReadyState() == XMLHttpRequest.DONE) { xhr.clearOnReadyStateChange(); fireOnResponseReceivedVltr(request, PromiseReqBuilder.this); } } }); try { JsUtils.runJavascriptFunction(xmlHttpRequest, "send", isFormData ? data.getDataImpl() : settings.getDataString()); } catch (JavaScriptException e) { onError(null, e); } } public void onError(Request request, Throwable exception) { dfd.reject(exception, request); } public void onResponseReceived(Request request, Response response) { int status = response.getStatusCode(); if (status <= 0 || status >= 400) { String statusText = status <= 0 ? "Bad CORS" : response.getStatusText(); onError(request, new RequestException("HTTP ERROR: " + status + " " + statusText + "\n" + response.getText())); } else { dfd.resolve(response, request); } } /** * Using violator pattern to execute private method. */ private native void fireOnResponseReceivedVltr(Request rq, RequestCallback cb) /*-{ rq.@com.google.gwt.http.client.Request::fireOnResponseReceived(Lcom/google/gwt/http/client/RequestCallback;)(cb); }-*/; /** * Using violator pattern to use protected constructor. */ private native Request createRequestVltr(XMLHttpRequest rq, int ms, RequestCallback cb) /*-{ return @com.google.gwt.http.client.Request::new(Lcom/google/gwt/xhr/client/XMLHttpRequest;ILcom/google/gwt/http/client/RequestCallback;)(rq, ms, cb); }-*/; }