Java tutorial
/* * Copyright 2008 Google Inc. * * 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.google.gwt.gdata.sample.hellogdata.client; import com.google.gwt.accounts.client.AuthSubStatus; import com.google.gwt.accounts.client.User; import com.google.gwt.event.dom.client.ClickEvent; import com.google.gwt.event.dom.client.ClickHandler; import com.google.gwt.gdata.client.GData; import com.google.gwt.gdata.client.GDataSystemPackage; import com.google.gwt.gdata.client.atom.Text; import com.google.gwt.gdata.client.gbase.Attribute; import com.google.gwt.gdata.client.gbase.GoogleBaseService; import com.google.gwt.gdata.client.gbase.ItemsEntry; import com.google.gwt.gdata.client.gbase.ItemsEntryCallback; import com.google.gwt.gdata.client.impl.CallErrorException; import com.google.gwt.user.client.ui.Button; import com.google.gwt.user.client.ui.FlexTable; import com.google.gwt.user.client.ui.Label; /** * The following example demonstrates how to create an item. */ public class GoogleBaseCreateItemDemo extends GDataDemo { /** * This method is used by the main sample app to obtain * information on this sample and a sample instance. * * @return An instance of this demo. */ public static GDataDemoInfo init() { return new GDataDemoInfo() { @Override public GDataDemo createInstance() { return new GoogleBaseCreateItemDemo(); } @Override public String getDescription() { return "<p>This sample demonstrates how to create and insert " + "a new item. The items feed post URL " + "(http://www.google.com/base/feeds/items) is used to insert a " + "new item entry for the authenticated user.</p>"; } @Override public String getName() { return "Base - Creating an item"; } }; } private GoogleBaseService service; private FlexTable mainPanel; private final String scope = "http://www.google.com/base/feeds/"; /** * Setup the Google Base service and create the main content panel. * If the user is not logged on to Google Base display a message, * otherwise start the demo by creating an item. */ public GoogleBaseCreateItemDemo() { mainPanel = new FlexTable(); initWidget(mainPanel); if (!GData.isLoaded(GDataSystemPackage.GBASE)) { showStatus("Loading the GData Google-Base package...", false); GData.loadGDataApi(GDATA_API_KEY, new Runnable() { public void run() { startDemo(); } }, GDataSystemPackage.GBASE); } else { startDemo(); } } /** * Create an item by inserting an item entry into * an items feed. * Set the item's title to an arbitrary string. Here * we prefix the title with 'GWT-GoogleBase-Client' so that * we can identify which items were created by this demo. * The new item is created as a product review with values * for the default product review attributes. * On success and failure, display a status message. * * @param itemsFeedUri The uri of the items feed into which * to insert the new item entry */ private void createItem(String itemsFeedUri) { showStatus("Creating item...", false); ItemsEntry entry = ItemsEntry.newInstance(); entry.setTitle(Text.newInstance()); entry.getTitle().setText("GWT-GoogleBase-Client - inserted item"); entry.setContent(Text.newInstance()); entry.getContent().setText("GData is great data!! :)"); Attribute targetCountry = Attribute.newInstance(); targetCountry.setValue("US"); Attribute reviewType = Attribute.newInstance(); reviewType.setValue("Product Review"); Attribute nameOfItem = Attribute.newInstance(); nameOfItem.setValue("gwt-gdata"); Attribute expirationDate = Attribute.newInstance(); expirationDate.setValue("2038-01-19T03:14:07Z"); Attribute rating = Attribute.newInstance(); rating.setValue("5-Excellent"); Attribute customerId = Attribute.newInstance(); customerId.setValue("5752122"); Attribute itemType = Attribute.newInstance(); itemType.setValue("Reviews"); Attribute itemLanguage = Attribute.newInstance(); itemLanguage.setValue("en"); entry.setAttribute("target_country", targetCountry); entry.setAttribute("review_type", reviewType); entry.setAttribute("name_of_item_reviewed", nameOfItem); entry.setAttribute("expiration_date", expirationDate); entry.setAttribute("rating", rating); entry.setAttribute("customer_id", customerId); entry.setAttribute("item_type", itemType); entry.setAttribute("item_language", itemLanguage); service.insertEntry(itemsFeedUri, entry, new ItemsEntryCallback() { public void onFailure(CallErrorException caught) { showStatus("An error occurred while creating an item: " + caught.getMessage(), true); } public void onSuccess(ItemsEntry result) { showStatus("Created an item.", false); } }); } /** * Displays a status message to the user. * * @param message The message to display. * @param isError Indicates whether the status is an error status. */ private void showStatus(String message, boolean isError) { mainPanel.clear(); mainPanel.insertRow(0); mainPanel.addCell(0); Label msg = new Label(message); if (isError) { msg.setStylePrimaryName("hm-error"); } mainPanel.setWidget(0, 0, msg); } /** * Starts this demo. */ private void startDemo() { service = GoogleBaseService.newInstance("HelloGData_GoogleBase_CreateItemDemo_v2.0"); if (User.getStatus(scope) == AuthSubStatus.LOGGED_IN) { Button startButton = new Button("Create an item"); startButton.addClickHandler(new ClickHandler() { public void onClick(ClickEvent event) { createItem("http://www.google.com/base/feeds/items"); } }); mainPanel.setWidget(0, 0, startButton); } else { showStatus("You are not logged on to Google Base.", true); } } }