Java tutorial
/* * Copyright (c) 2005-2011 Grameen Foundation USA * 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. * * See also http://www.apache.org/licenses/LICENSE-2.0.html for an * explanation of the license and how it is applied. */ package org.mifos.framework.components.mifosmenu; import java.io.IOException; import javax.xml.XMLConstants; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import javax.xml.transform.stream.StreamSource; import javax.xml.validation.Schema; import javax.xml.validation.SchemaFactory; import org.apache.commons.lang.StringUtils; import org.mifos.config.business.MifosConfigurationManager; import org.mifos.core.MifosResourceUtil; import org.mifos.framework.exceptions.MenuParseException; import org.mifos.framework.exceptions.SystemException; import org.mifos.framework.util.helpers.FilePaths; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.xml.sax.SAXException; import org.xml.sax.SAXParseException; /** * It parses xml, builds and return crude menu for application */ public class MenuParser { /** * Method to parse xml and return crude menu * * @return array of crude Menu objects */ public static Menu[] parse() throws SystemException { try { DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); SchemaFactory schfactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI); schfactory.setErrorHandler(null); Schema schema = schfactory.newSchema( new StreamSource(MifosResourceUtil.getClassPathResourceAsStream(FilePaths.MENUSCHEMA))); factory.setNamespaceAware(false); factory.setValidating(false); factory.setSchema(schema); DocumentBuilder builder = factory.newDocumentBuilder(); Document document = builder.parse(MifosResourceUtil.getClassPathResourceAsStream(FilePaths.MENUPATH)); NodeList tabNodeList = document.getElementsByTagName(MenuConstants.TOPMENUTAB); Menu leftMenus[] = new Menu[tabNodeList.getLength()]; for (int i = 0; i < tabNodeList.getLength(); i++) { leftMenus[i] = new Menu(); leftMenus[i].setTopMenuTabName(((Element) tabNodeList.item(i)).getAttribute(MenuConstants.NAME)); leftMenus[i].setMenuGroups(createMenuGroup(tabNodeList.item(i))); String menuHeading = ((Element) tabNodeList.item(i)) .getElementsByTagName(MenuConstants.LEFTMENULABEL).item(0).getFirstChild().getTextContent() .trim(); leftMenus[i].setMenuHeading(menuHeading); } return leftMenus; } catch (SAXParseException spe) { throw new MenuParseException(spe); } catch (SAXException sxe) { throw new MenuParseException(sxe); } catch (ParserConfigurationException pce) { throw new MenuParseException(pce); } catch (IOException ioe) { throw new MenuParseException(ioe); } } /** * Method to build crude MenuGroup objects for a given top-menu-tab * * @param leftMenu * is the root node for a top-menu-tab * @return array of MenuGroup objects */ static MenuGroup[] createMenuGroup(Node leftMenu) throws SystemException { NodeList menuGpNodeList = ((Element) leftMenu).getElementsByTagName(MenuConstants.MENUGROUP); MenuGroup menuGroup[] = new MenuGroup[menuGpNodeList.getLength()]; for (int i = 0; i < menuGpNodeList.getLength(); i++) { menuGroup[i] = new MenuGroup(); menuGroup[i].setMenuItems(createMenuItems(menuGpNodeList.item(i))); menuGroup[i].setDisplayName(getDisplayName((Element) menuGpNodeList.item(i))); } return menuGroup; } /** * Method to build crude MenuItem objects for a MenuGroup * * @param menuGroup * is the root node for MenuGroup. * @return array of MenuItem objects */ static MenuItem[] createMenuItems(Node menuGroup) throws SystemException { NodeList menuItemNodeList = ((Element) menuGroup).getElementsByTagName(MenuConstants.MENUITEM); MenuItem menuItem[] = new MenuItem[menuItemNodeList.getLength()]; int hiddenItems = 0; for (int i = 0, j = 0; i < menuItemNodeList.getLength(); i++) { if (isMenuItemVisible((Element) menuItemNodeList.item(i))) { menuItem[j] = new MenuItem(); menuItem[j].setDisplayName(getDisplayName((Element) menuItemNodeList.item(i))); menuItem[j].setLinkValue(getLinkValue((Element) menuItemNodeList.item(i))); j++; } else { hiddenItems++; } } if (hiddenItems > 0) { menuItem = removeEmptyMenuItems(menuItem, hiddenItems); } return menuItem; } private static MenuItem[] removeEmptyMenuItems(MenuItem menuItems[], int hiddenItems) { MenuItem newMenuItems[] = new MenuItem[menuItems.length - hiddenItems]; for (int i = 0, j = 0; i < menuItems.length; i++) { if (menuItems[i] != null) { newMenuItems[j++] = menuItems[i]; } } return newMenuItems; } /** * Uses boolean keys in the application-wide configuration to determine if * menu items should be displayed. Missing keys will cause * {@link java.util.NoSuchElementException} to be thrown. Keys are * configured in menu.xml. */ private static boolean isMenuItemVisible(Element element) { String visiKey = element.getAttribute(MenuConstants.KEY_FOR_HIDDEN); if (StringUtils.isNotBlank(visiKey)) { MifosConfigurationManager cm = MifosConfigurationManager.getInstance(); return cm.getBoolean(visiKey); } // if attribute doesn't exist, a configuration key wasn't specified, // so menu item must be visible return true; } /** * Method to get all keys for a displayname of a given node * * @param node * is the element whose display name is to be obtained * @return array of keys respective to display name */ static String[] getDisplayName(Element node) { NodeList displaynameNodeList = node.getElementsByTagName(MenuConstants.DISPLAYNAME); NodeList nameNodeList = ((Element) displaynameNodeList.item(0)) .getElementsByTagName(MenuConstants.NAMEFRAGMENT); String displayNameStr[] = new String[nameNodeList.getLength()]; for (int i = 0; i < nameNodeList.getLength(); i++) { displayNameStr[i] = nameNodeList.item(i).getFirstChild().getTextContent().trim(); } return displayNameStr; } /** * Method to get link value for a menu item * * @param node * is the menu item whose link is to be obtained * @return link as string */ static String getLinkValue(Element node) { return node.getElementsByTagName(MenuConstants.LINKVALUE).item(0).getFirstChild().getTextContent().trim(); } }