GWT 和 XML，GWTXML,一个非常简单的XML例子

GWT 和 XML，GWTXML,一个非常简单的XML例子

一个非常简单的XML例子用来掩饰在页面上显示客户资料的方法

SimpleXML.java

/** * Copyright 2006 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.sample.simplexml.client;import com.google.gwt.core.client.EntryPoint;import com.google.gwt.user.client.HTTPRequest;import com.google.gwt.user.client.ResponseTextHandler;import com.google.gwt.user.client.ui.FlexTable;import com.google.gwt.user.client.ui.FlowPanel;import com.google.gwt.user.client.ui.HTML;import com.google.gwt.user.client.ui.HTMLTable;import com.google.gwt.user.client.ui.Label;import com.google.gwt.user.client.ui.RootPanel;import com.google.gwt.user.client.ui.TabPanel;import com.google.gwt.xml.client.Document;import com.google.gwt.xml.client.Element;import com.google.gwt.xml.client.Node;import com.google.gwt.xml.client.NodeList;import com.google.gwt.xml.client.XMLParser;/** * A very simple XML Example where we take a customer profile and display it on * a page. */public class SimpleXML implements EntryPoint {  private static final String XML_LABEL_STYLE = "xmlLabel";  private static final String USER_TABLE_LABEL_STYLE = "userTableLabel";  private static final String USER_TABLE_STYLE = "userTable";  private static final String NOTES_STYLE = "notes";  public void onModuleLoad() {    HTTPRequest.asyncGet("customerRecord.xml", new ResponseTextHandler() {      public void onCompletion(String responseText) {        // In the real world, this text would come as a RPC response. This        // technique is great for testing and samples though!        renderXML(responseText);      }      private FlexTable createOrderTable(FlowPanel xmlParsed, String label) {        HTML orderTableLabel = new HTML("<h2>" + label + "</h2>");        xmlParsed.add(orderTableLabel);        FlexTable orderTable = new FlexTable();        orderTable.setStyleName(USER_TABLE_STYLE);        orderTable.setBorderWidth(3);        orderTable.getRowFormatter().setStyleName(0, USER_TABLE_LABEL_STYLE);        orderTable.setText(0, 0, "Order ID");        orderTable.setText(0, 1, "Item");        orderTable.setText(0, 2, "Ordered On");        orderTable.setText(0, 3, "Street");        orderTable.setText(0, 4, "City");        orderTable.setText(0, 5, "State");        orderTable.setText(0, 6, "Zip");        xmlParsed.add(orderTable);        return orderTable;      }      /**       * Creates the xml representation of xmlText. xmlText is assumed to have       * been validated for structure on the server.       *        * @param xmlText xml text       * @param xmlParsed panel to display customer record       */      private void customerPane(String xmlText, FlowPanel xmlParsed) {        Document customerDom = XMLParser.parse(xmlText);        Element customerElement = customerDom.getDocumentElement();        // Must do this if you ever use a raw node list that you expect to be        // all elements.        XMLParser.removeWhitespace(customerElement);        // Customer Name        String nameValue = getElementTextValue(customerElement, "name");        String title = "<h1>" + nameValue + "</h1>";        HTML titleHTML = new HTML(title);        xmlParsed.add(titleHTML);        // Customer Notes        String notesValue = getElementTextValue(customerElement, "notes");        Label notesText = new Label();        notesText.setStyleName(NOTES_STYLE);        notesText.setText(notesValue);        xmlParsed.add(notesText);        // Pending orders UI setup        FlexTable pendingTable = createOrderTable(xmlParsed, "Pending Orders");        FlexTable completedTable = createOrderTable(xmlParsed, "Completed");        completedTable.setText(0, 7, "Shipped by");        // Fill Orders Table        NodeList orders = customerElement.getElementsByTagName("order");        int pendingRowPos = 0;        int completedRowPos = 0;        for (int i = 0; i < orders.getLength(); i++) {          Element order = (Element) orders.item(i);          HTMLTable table;          int rowPos;          if (order.getAttribute("status").equals("pending")) {            table = pendingTable;            rowPos = ++pendingRowPos;          } else {            table = completedTable;            rowPos = ++completedRowPos;          }          int columnPos = 0;          fillInOrderTableRow(customerElement, order, table, rowPos, columnPos);        }      }      private void fillInOrderTableRow(Element customerElement, Element order,          HTMLTable table, int rowPos, int columnPos) {        // Order ID        String orderId = order.getAttribute("id");        table.setText(rowPos, columnPos++, orderId);        // Item        Element item = (Element) order.getElementsByTagName("item").item(0);        String itemUPC = item.getAttribute("upc");        String itemName = item.getFirstChild().getNodeValue();        Label itemLabel = new Label(itemUPC);        itemLabel.setTitle(itemName);        table.setWidget(rowPos, columnPos++, itemLabel);        // Ordered On        String orderedOnValue = getElementTextValue(customerElement,          "orderedOn");        table.setText(rowPos, columnPos++, orderedOnValue);        // Address        Element address = (Element) order.getElementsByTagName("address").item(          0);        XMLParser.removeWhitespace(address);        NodeList lst = address.getChildNodes();        for (int j = 0; j < lst.getLength(); j++) {          Element next = (Element) lst.item(j);          String addressPartText = next.getFirstChild().getNodeValue();          table.setText(rowPos, columnPos++, addressPartText);        }        // Shipped By (optional attribute)        NodeList shippedByList = order.getElementsByTagName("shippingInfo");        if (shippedByList.getLength() == 1) {          Element shippedBy = (Element) shippedByList.item(0);          // Depending upon the shipper, different attributes might be          // available, so XML carries the display info          FlexTable shippedByTable = new FlexTable();          shippedByTable.getRowFormatter().setStyleName(0,            USER_TABLE_LABEL_STYLE);          shippedByTable.setBorderWidth(1);          NodeList shippedByParts = shippedBy.getChildNodes();          for (int j = 0; j < shippedByParts.getLength(); j++) {            Node next = shippedByParts.item(j);            Element elem = (Element) next;            shippedByTable.setText(0, j, elem.getAttribute("title"));            shippedByTable.setText(1, j, elem.getFirstChild().getNodeValue());          }          table.setWidget(rowPos, columnPos++, shippedByTable);        }      }      /**       * Utility method to return the values of elements of the form <myTag>tag       * value</myTag>       */      private String getElementTextValue(Element parent, String elementTag) {        // If the xml is not coming from a known good source, this method would        // have to include safety checks.        return parent.getElementsByTagName(elementTag).item(0).getFirstChild()          .getNodeValue();      }      private void renderXML(String xmlText) {        final TabPanel tab = new TabPanel();        final FlowPanel xmlSource = new FlowPanel();        final FlowPanel xmlParsed = new FlowPanel();        tab.add(xmlParsed, "Customer Pane");        tab.add(xmlSource, "XML Source");        tab.selectTab(0);        RootPanel.get().add(tab);        xmlPane(xmlText, xmlSource);        customerPane(xmlText, xmlParsed);      }      /**       * Show the raw XML.       *        * @param xmlText       * @param xmlSource       */      private void xmlPane(String xmlText, final FlowPanel xmlSource) {        xmlText = xmlText.replaceAll("<", "&#60;");        xmlText = xmlText.replaceAll(">", "&#62;");        Label xml = new HTML("<pre>" + xmlText + "</pre>", false);        xml.setStyleName(XML_LABEL_STYLE);        xmlSource.add(xml);      }    });  }}