menutag.java

一个实用工具类

/*
 * Copyright (C) butor.com. All rights reserved.
 *
 * This software is published under the terms of the GNU Library General
 * Public License (GNU LGPL), a copy of which has been included with this
 * distribution in the LICENSE.txt file. 
 */


package org.butor.web.taglib.html;

import java.io.IOException;
import java.util.Iterator;
import java.util.Locale;

import javax.servlet.http.HttpSession;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.TagSupport;

import org.butor.context.ContextService;
import org.butor.context.IContext;
import org.butor.log.Log;
import org.butor.security.ISecurityChecker;
import org.butor.web.menu.IMenuItem;
import org.butor.web.menu.ButorMenu;
import org.butor.web.menu.ButorMenuFactory;
import org.butor.web.menu.MenuLabelComparator;
import org.butor.web.menu.MenuSequenceComparator;


/**
 * This class renders the <menu> tag. Currently support two sorting modes: by label or by sequence.
 * Also the menu can be displayed on both orientation, vertically and horizontally. Note that when 
 * displayed in the horizontal orientation, only the first level menu items are displayed.
 * 
 * Usage example:
 * 		<menu:menu id="app" orientation="vertical" sort="label" />
 *
 * @author Nguyen The Hung
 */
public class MenuTag extends TagSupport {
	
	public static final String ORIENTATION_VERT = "vertical";
	public static final String ORIENTATION_HORZ = "horizontal";
	public static final String SORT_LABEL = "label";
	public static final String SORT_SEQ = "sequence";
	
	private String f_menuId;
	private String f_orientation = ORIENTATION_VERT;
	private String f_sort = SORT_SEQ;
	private String f_styleClass;
	private String f_dynamic = "false";
	private String f_top = "20" ;
	private String f_left = "120" ;
	private String f_lowBgColor="#FF0000";			// Background color when mouse is not over
	private String f_lowSubBgColor="#FF0000";		// Background color when mouse is not over on subs
	private String f_highBgColor="#B20505";			// Background color when mouse is over
	private String f_highSubBgColor="#B20505";		// Background color when mouse is over on subs
	private String f_fontLowColor="black";			// Font color when mouse is not over
	private String f_fontSubLowColor="black";		// Font color subs when mouse is not over
	private String f_fontHighColor="white";			// Font color when mouse is over
	private String f_fontSubHighColor="white";		// Font color subs when mouse is over
	private String f_borderColor="black";			// Border color
	private String f_borderSubColor="black";		// Border color for subs
	private String f_borderWidth="1";				// Border width
	private String f_borderBtwnElmnts="1";			// Border between elements 1 or 0
	
	/**
	 * Get the menu object.
	 * @return org.butor.wak.menu.ButorMenu
	 */
	protected ButorMenu getMenu() {
		Locale locale = null;
		ButorMenu menu = null;
		ISecurityChecker securityChecker = null;
		boolean hasChanged = false;

		// Try to get the menu from the session
		HttpSession session = pageContext.getSession();
		if (session != null) {
			menu = (ButorMenu) session.getAttribute("menu." +f_menuId);
			
			Object contextKey = Thread.currentThread();
			IContext context = ContextService.getContext(contextKey);
			if (context == null) {
				Log.logStr(this, Log.LOG_TYPE_WARN, "getMenu()", 
					"Can't find context.");
			}

			locale = context.getLocale();
			securityChecker = context.getSecurityChecker();	
					
			if (securityChecker == null) {
				Log.logStr(this, Log.LOG_TYPE_WARN, "getMenu()", 
					"Can't find security checker in context.");
			}
			if (menu != null) {
				Log.logStr(Log.LOG_LEVEL_LOW, this, Log.LOG_TYPE_INFO, "getMenu()", 
					"Found menu in session.");
			}
		} 
		
		
		if (menu == null) {
			// menu does not exist, then build it.
			menu = ButorMenuFactory.getMenu(f_menuId, locale == null ? Locale.ENGLISH : locale, securityChecker);
			hasChanged = true;
		} else {
			if (locale != null && locale != menu.getLocale()) {
				menu.setLocale(locale);
				hasChanged = true;
			} else if (f_sort.equals(SORT_SEQ)) {
				if (!(menu.getComparator() instanceof MenuSequenceComparator)) {
					hasChanged = true;
				}
			} else {
				if (!(menu.getComparator() instanceof MenuLabelComparator)) {
					hasChanged = true;
				}
			}
		}
		
		if (menu != null && hasChanged) {
			
			if (f_sort.equals(SORT_SEQ)) {
				menu.setComparator(new MenuSequenceComparator());
			} else {
				menu.setComparator(new MenuLabelComparator());
			}
			menu.sort();

			if (session != null) {
				session.setAttribute("menu." +f_menuId, menu);
			}
		}
		
		return menu;
	}
	
	/**
	 * Indenting
	 */
	protected void printEmptyColumn(JspWriter writer) throws IOException  {

		writer.print("&nbsp;&nbsp;&nbsp;&nbsp;");
	}
	
	/**
	 * Print the link
	 */
	protected void printLink(JspWriter writer, IMenuItem item) throws IOException {
		String action = item.getAction();
		 String target = item.getTarget();
        
		if (item.isTitledAction()) {
			action = item.getActionWithTitle();
		}
		
		String label = item.getLabel();
		
		if (action == null || "".equals(action)) {
			if (label != null) {
				writer.print(label);
			}
		} else {
			writer.print("<a href=\"");
			writer.print(action);			
			if (target != null && target.trim().length() > 0) {
                writer.print("\"");
                writer.print(" target=\"");
                writer.print(target);                
            }
			writer.print("\">");
			
			if (f_styleClass != null) {
				writer.print("<span class=" + f_styleClass + ">");
			}			
			if (label != null) {
				writer.print(label);
			}
			if (f_styleClass != null) {
				writer.print("</span>");
			}
			
			writer.print("</a>");
		}
	}
	
	protected void printDynamicLink(JspWriter writer, IMenuItem menuItems[], int index) throws IOException {
		IMenuItem item = menuItems[index];
		String action = item.getAction();
		String label = item.getLabel();
		String target = item.getTarget();
		
		Object contextKey = Thread.currentThread();
		IContext context = ContextService.getContext(contextKey);
		if (context == null) {
			Log.logStr(this, Log.LOG_TYPE_WARN, "printDynamicLink()", 
				"Can't find context.");
		}

		Locale locale = context.getLocale();
			
		writer.print("<a href=\"");
		if (action == null || action.equals("")) {
			writer.print("#");
		} else {
			writer.print(action);
		}
		IMenuItem currentDisplayedItem = null; 
		StringBuffer sb = new StringBuffer();
		writer.print("\" onmouseover=\"affiche(");
		for ( int i=0; i<menuItems.length; i++ ) {
			String selectedAction = pageContext.getRequest().getParameter(menuItems[i].getName());
			if ( selectedAction != null ) {
				currentDisplayedItem = menuItems[i];
			}
			sb.append("'");
			sb.append(menuItems[i].getName());
			sb.append("','");
			sb.append(menuItems[i].getImageUrl());
			if ( menuItems[i].isImageDependOnLanguage() ) {
				sb.append(locale.getLanguage() + ".gif");
			}
			sb.append("',");
		}
		writer.print(sb.toString());
		writer.print("'");
		writer.print(item.getName());
		writer.print("','");
		writer.print(item.getImageOverUrl());
		if ( item.isImageDependOnLanguage() ) {
			writer.print(locale.getLanguage() + ".gif");
		}
		writer.print("')\" onmouseout=\"quit('" + item.getName() + "', ");
		writer.print(sb.toString());
		if ( currentDisplayedItem != null ) {
			writer.print("'");
			writer.print(currentDisplayedItem.getName());
			writer.print("','");
			writer.print(currentDisplayedItem.getImageOverUrl());
			if ( currentDisplayedItem.isImageDependOnLanguage() ) {
				writer.print(locale.getLanguage() + ".gif");
			}
		} else {
			writer.print("'', '");
		}
		writer.print("')");
		if (target != null && target.trim().length() > 0) {
            writer.print(" target=\"");
            writer.print(target);                
        }
		writer.print("\">");
		
		if (f_styleClass != null) {
			writer.print("<span class=" + f_styleClass + ">");
		}
		if ( item.getImageUrl() != null ) {
			writer.print("<IMG src=\"" + item.getImageUrl());
			if ( item.isImageDependOnLanguage() ) {
				writer.print(locale.getLanguage() + ".gif");
			}
			writer.print("\" border=0 name=" + item.getName() + ">");
		}
		if ( (label != null) && (!label.equals("")) ) {
			writer.print(label);
		}
		if (f_styleClass != null) {
			writer.print("</span>");
		}
		
		writer.print("</a>");
	}
	
	//return true if their is an item that is passed as a request parameter. Because if not we'll search 
	// for the selected Link in the session.
	private boolean getSelectedLinkFromSession(IMenuItem[] items) {
		boolean found = false;
		int i=0;
		while ( (!found) && (i < items.length) ) {
			found = (pageContext.getRequest().getParameter(items[i++].getName()) != null);
		}
		return !found;
	}
	
	/**
	 * Recursively print the menu items
	 */
	protected void printMenu(JspWriter writer, IMenuItem item, int level, boolean getSelectionFromSession) throws IOException {
		if (f_orientation.equals(ORIENTATION_VERT)) {
			writer.print("<tr>");
			writer.print("<td nowrap>");
			for (int i = 0; i < level; i++) {
				printEmptyColumn(writer);
			}
			// print the +/- gif
			if (item.hasChild()) {
				writer.print("<img src=\"/_images/down_red.gif\">");
			} else {
				writer.print("<img src=\"/_images/right_red.gif\">");
			}
			// print the menu
			printLink(writer, item);
			writer.print("</td>");
			writer.print("</tr>\n");
			
			// print the sub-menu
			for (Iterator it = item.getChildren().iterator(); it.hasNext();) {
				IMenuItem child = (IMenuItem) it.next();
				printMenu(writer, child, level + 1, false);
			}
		} else {
			Object contextKey = Thread.currentThread();
			IContext context = ContextService.getContext(contextKey);
			if (context == null) {
				Log.logStr(this, Log.LOG_TYPE_WARN, "printDynamicLink()", 
					"Can't find context.");
			}
	
			Locale locale = context.getLocale();

			String imageUrl = item.getImageUrl();
			if ( ( imageUrl != null ) && ( !imageUrl.equals("")) ) {
				String selectedLink = pageContext.getRequest().getParameter(item.getName());
				if ( (selectedLink != null) || ( (getSelectionFromSession) && (pageContext.getAttribute(item.getName(),PageContext.SESSION_SCOPE) != null) ) ) {
					pageContext.setAttribute(item.getName(), "", PageContext.SESSION_SCOPE);
					writer.print("<IMG name='" + item.getName() + "' SRC=\""+ item.getImageClickUrl());
					if ( item.isImageDependOnLanguage() ) {
						writer.print(locale.getLanguage() + ".gif");
					}
					writer.print("\">");
				} else {
					pageContext.removeAttribute(item.getName(), PageContext.SESSION_SCOPE);
					writer.print("<IMG name='" + item.getName() + "' SRC=\"" + imageUrl);
					if ( item.isImageDependOnLanguage() ) {
						writer.print(locale.getLanguage() + ".gif");
					}
					writer.print(" \">");
				}
			}
			printLink(writer, item);
		}
	}
	
	protected void createDynamicMenu(JspWriter writer, IMenuItem item, String suffix, Locale locale) throws IOException {
		writer.print("Menu");
		writer.print(suffix);
		writer.print("=new Array(\"");
		if ( item.getImageUrl() != null ) {
			writer.print("rollover:");
			writer.print(item.getImageUrl());
			if ( item.isImageDependOnLanguage() ) {
				writer.print(locale.getLanguage() + ".gif");
			}
			writer.print(":");
			if ( item.getImageOverUrl() != null) {
				writer.print(item.getImageOverUrl());
				if ( item.isImageDependOnLanguage() ) {
					writer.print(locale.getLanguage() + ".gif");
				}
			} else {
				writer.print(item.getImageUrl());
				if ( item.isImageDependOnLanguage() ) {
					writer.print(locale.getLanguage() + ".gif");
				}
			}
		} else {
			writer.print(item.getLabel());
		}
		writer.print("\",\"");
		writer.print(item.getAction());
		writer.print("\",\"\",");
		writer.print(( (item.getChildren()!= null) ? item.getChildren().size() : 0 ));
		writer.println(",");
		writer.print(item.getHeight());
		writer.print(",");
		writer.print(item.getWidth());
		if ( item.getImageUrl() != null ) {
			writer.print(", \"");
			writer.print(item.getLabel());
			writer.print("\"");
		}
		writer.println(");");
		// print the sub-menu
		for (int it = 0; it < item.getChildren().toArray().length; it++) {
			IMenuItem child = (IMenuItem) item.getChildren().toArray()[it];
			createDynamicMenu(writer, child, suffix + "_" + (it+1), locale);
		}
	}
	protected void printMenu(JspWriter writer, IMenuItem menuItems[], int index, int level) throws IOException {
		printDynamicLink(writer, menuItems, index) ;
		
	}
	
	protected void printSubMenu(JspWriter writer, IMenuItem menuItems[], int index) throws IOException {
		Object contextKey = Thread.currentThread();
		IContext context = ContextService.getContext(contextKey);
		if (context == null) {
			Log.logStr(this, Log.LOG_TYPE_WARN, "printSubMenu()", 
				"Can't find context.");
		}

		Locale locale = context.getLocale();
		
		IMenuItem item = menuItems[index];
		writer.print("<DIV id=box" + item.getName() + " class=\"subMenu\">\n");
		if ( item.hasChild() ) {
			writer.print("<TABLE cellSpacing=0 cellPadding=0 border=0>\n");
			writer.print("<TR>\n");
			// print the sub-menu
			int i=0;
			boolean isDependOnLan = false;
			for (Iterator it = item.getChildren().iterator(); it.hasNext();) {
				IMenuItem child = (IMenuItem) it.next();			
			    writer.print("<TD align=CENTER>\n");
			    writer.print("<a href=\"javascript:Go('" + child.getName() + "')\"   onmouseover=\"quit('stop');swapImage('SM" + child.getName() + "','','" + child.getImageOverUrl());
			    isDependOnLan = child.isImageDependOnLanguage();
			    if ( isDependOnLan ) {
				    writer.print(locale.getLanguage() + ".gif");
			    }
			    writer.print("',1)\"     onmouseout=\"swapImage('SM" + child.getName() + "','','" + child.getImageUrl());
			    if ( isDependOnLan ) {
				    writer.print(locale.getLanguage() + ".gif");
			    }
			    writer.print("',1);quit('submenu')\" ><IMG SRC=\"" + child.getImageUrl());
			    if ( isDependOnLan ) {
				    writer.print(locale.getLanguage() + ".gif");
			    }
			    writer.print("\"   border=0 name=\"SM" + child.getName() + "\"  >");
			    if (child.getLabel() != null && (!child.getLabel().equals(""))) {
			    	writer.print(child.getLabel());
			    }
			    
			    writer.print("</a>\n");