package org.apache.velocity.tools.view.servlet;
   
   /*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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 java.io.InputStream;
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.Map;
  
  import javax.servlet.ServletContext;
  import javax.servlet.http.HttpSession;
  
  import org.apache.commons.digester.RuleSet;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.velocity.tools.view.ToolInfo;
  import org.apache.velocity.tools.view.XMLToolboxManager;
  import org.apache.velocity.tools.view.context.ViewContext;
  import org.apache.velocity.tools.view.ServletUtils;
  
  
  /**
   * <p>A toolbox manager for the servlet environment.</p>
   *
   * <p>A toolbox manager is responsible for automatically filling the Velocity
   * context with a set of view tools. This class provides the following
   * features:</p>
   * <ul>
   *   <li>configurable through an XML-based configuration file</li>
   *   <li>assembles a set of view tools (the toolbox) on request</li>
   *   <li>handles different tool scopes (request, session, application)</li>
   *   <li>supports any class with a public constructor without parameters
   *     to be used as a view tool</li>
   *   <li>supports adding primitive data values to the context(String,Number,Boolean)</li>
   * </ul>
   *
   *
   * <p><strong>Configuration</strong></p>
   * <p>The toolbox manager is configured through an XML-based configuration
   * file. The configuration file is passed to the {@link #load(java.io.InputStream input)}
   * method. The format is shown in the following example:</p>
   * <pre>
   * &lt;?xml version="1.0"?&gt;
   *
   * &lt;toolbox&gt;
   *   &lt;tool&gt;
   *      &lt;key&gt;link&lt;/key&gt;
   *      &lt;scope&gt;request&lt;/scope&gt;
   *      &lt;class&gt;org.apache.velocity.tools.view.tools.LinkTool&lt;/class&gt;
   *   &lt;/tool&gt;
   *   &lt;tool&gt;
   *      &lt;key&gt;date&lt;/key&gt;
   *      &lt;scope&gt;application&lt;/scope&gt;
   *      &lt;class&gt;org.apache.velocity.tools.generic.DateTool&lt;/class&gt;
   *   &lt;/tool&gt;
   *   &lt;data type="number"&gt;
   *      &lt;key&gt;luckynumber&lt;/key&gt;
   *      &lt;value&gt;1.37&lt;/value&gt;
   *   &lt;/data&gt;
   *   &lt;data type="string"&gt;
   *      &lt;key&gt;greeting&lt;/key&gt;
   *      &lt;value&gt;Hello World!&lt;/value&gt;
   *   &lt;/data&gt;
   *   &lt;xhtml&gt;true&lt;/xhtml&gt;
   * &lt;/toolbox&gt;
   * </pre>
   * <p>The recommended location for the configuration file is the WEB-INF directory of the
   * web application.</p>
   *
   * @author <a href="mailto:sidler@teamup.com">Gabriel Sidler</a>
   * @author Nathan Bubna
   * @author <a href="mailto:geirm@apache.org">Geir Magnusson Jr.</a>
   * @author <a href="mailto:henning@schmiedehausen.org">Henning P. Schmiedehausen</a>
   * @version $Id: ServletToolboxManager.java 651470 2008-04-25 00:47:52Z nbubna $
   * @deprecated Use {@link org.apache.velocity.tools.config.XmlFactoryConfiguration}
   */
  @Deprecated
  public class ServletToolboxManager extends XMLToolboxManager
  {
  
      // --------------------------------------------------- Properties ---------
 
     public static final String SESSION_TOOLS_KEY =
         ServletToolboxManager.class.getName() + ":session-tools";
 
     protected static final Log LOG = LogFactory.getLog(ServletToolboxManager.class);
 
     private ServletContext servletContext;
     private Map appTools;
     private ArrayList sessionToolInfo;
     private ArrayList requestToolInfo;
     private boolean createSession;
 
     private static HashMap managersMap = new HashMap();
     private static RuleSet servletRuleSet = new ServletToolboxRuleSet();
 
 
     // --------------------------------------------------- Constructor --------
 
     /**
      * Use getInstance(ServletContext,String) instead
      * to ensure there is exactly one ServletToolboxManager
      * per xml toolbox configuration file.
      */
     private ServletToolboxManager(ServletContext servletContext)
     {
         this.servletContext = servletContext;
         appTools = new HashMap();
         sessionToolInfo = new ArrayList();
         requestToolInfo = new ArrayList();
         createSession = true;
 
         LOG.warn("ServletToolboxManager has been deprecated. Please use "+
                  "org.apache.velocity.tools.ToolboxFactory instead.");
     }
 
 
     // -------------------------------------------- Public Methods ------------
 
     /**
      * ServletToolboxManager factory method.
      * This method will ensure there is exactly one ServletToolboxManager
      * per xml toolbox configuration file.
      */
     public static synchronized ServletToolboxManager getInstance(ServletContext servletContext,
                                                                  String toolboxFile)
     {
         // little fix up
         if (!toolboxFile.startsWith("/"))
         {
             toolboxFile = "/" + toolboxFile;
         }
 
         // get the unique key for this toolbox file in this servlet context
         String uniqueKey = servletContext.hashCode() + ':' + toolboxFile;
 
         // check if an instance already exists
         ServletToolboxManager toolboxManager =
             (ServletToolboxManager)managersMap.get(uniqueKey);
 
         if (toolboxManager == null)
         {
             // if not, build one
             InputStream is = null;
             try
             {
                 // get the bits
                 is = servletContext.getResourceAsStream(toolboxFile);
 
                 if (is != null)
                 {
                     LOG.info("Using config file '" + toolboxFile + "'");
 
                     toolboxManager = new ServletToolboxManager(servletContext);
                     toolboxManager.load(is);
 
                     // remember it
                     managersMap.put(uniqueKey, toolboxManager);
 
                     LOG.debug("Toolbox setup complete.");
                 }
                 else
                 {
                     LOG.debug("No toolbox was found at '" + toolboxFile + "'");
                 }
             }
             catch(Exception e)
             {
                 LOG.error("Problem loading toolbox '" + toolboxFile + "'", e);
             }
             finally
             {
                 try
                 {
                     if (is != null)
                     {
                         is.close();
                     }
                 }
                 catch(Exception ee) {}
             }
         }
         return toolboxManager;
     }
 
 
     /**
      * <p>Sets whether or not to create a new session when none exists for the
      * current request and session-scoped tools have been defined for this
      * toolbox.</p>
      *
      * <p>If true, then a call to {@link #getToolbox(Object)} will
      * create a new session if none currently exists for this request and
      * the toolbox has one or more session-scoped tools designed.</p>
      *
      * <p>If false, then a call to getToolbox(Object) will never
      * create a new session for the current request.
      * This effectively means that no session-scoped tools will be added to
      * the ToolboxContext for a request that does not have a session object.
      * </p>
      *
      * The default value is true.
      */
     public void setCreateSession(boolean b)
     {
         createSession = b;
         LOG.debug("create-session is set to " + b);
     }
 
 
     /**
      * <p>Sets an application attribute to tell velocimacros and tools
      * (especially the LinkTool) whether they should output XHTML or HTML.</p>
      *
      * @see ViewContext#XHTML
      * @since VelocityTools 1.1
      */
     public void setXhtml(Boolean value)
     {
         servletContext.setAttribute(ViewContext.XHTML, value);
         LOG.info(ViewContext.XHTML + " is set to " + value);
     }
 
 
     // ------------------------------ XMLToolboxManager Overrides -------------
 
     /**
      * <p>Retrieves the rule set Digester should use to parse and load
      * the toolbox for this manager.</p>
      *
      * <p>The DTD corresponding to the ServletToolboxRuleSet is:
      * <pre>
      *  &lt;?xml version="1.0"?&gt;
      *  &lt;!ELEMENT toolbox (create-session?,xhtml?,tool*,data*,#PCDATA)&gt;
      *  &lt;!ELEMENT create-session (#CDATA)&gt;
      *  &lt;!ELEMENT xhtml          (#CDATA)&gt;
      *  &lt;!ELEMENT tool           (key,scope?,class,parameter*,#PCDATA)&gt;
      *  &lt;!ELEMENT data           (key,value)&gt;
      *      &lt;!ATTLIST data type (string|number|boolean) "string"&gt;
      *  &lt;!ELEMENT key            (#CDATA)&gt;
      *  &lt;!ELEMENT scope          (#CDATA)&gt;
      *  &lt;!ELEMENT class          (#CDATA)&gt;
      *  &lt;!ELEMENT parameter (EMPTY)&gt;
      *      &lt;!ATTLIST parameter name CDATA #REQUIRED&gt;
      *      &lt;!ATTLIST parameter value CDATA #REQUIRED&gt;
      *  &lt;!ELEMENT value          (#CDATA)&gt;
      * </pre></p>
      *
      * @since VelocityTools 1.1
      */
     protected RuleSet getRuleSet()
     {
         return servletRuleSet;
     }
 
     /**
      * Ensures that application-scoped tools do not have request path
      * restrictions set for them, as those will not be enforced.
      *
      * @param info a ToolInfo object
      * @return true if the ToolInfo is valid
      * @since VelocityTools 1.3
      */
     protected boolean validateToolInfo(ToolInfo info)
     {
         if (!super.validateToolInfo(info))
         {
             return false;
         }
         if (info instanceof ServletToolInfo)
         {
             ServletToolInfo sti = (ServletToolInfo)info;
             if (sti.getRequestPath() != null &&
                 !ViewContext.REQUEST.equalsIgnoreCase(sti.getScope()))
             {
                 LOG.error(sti.getKey() + " must be a request-scoped tool to have a request path restriction!");
                 return false;
             }
         }
         return true;
     }
 
 
     /**
      * Overrides XMLToolboxManager to separate tools by scope.
      * For this to work, we obviously override getToolbox(Object) as well.
      */
     public void addTool(ToolInfo info)
     {
         if (validateToolInfo(info))
         {
             if (info instanceof ServletToolInfo)
             {
                 ServletToolInfo sti = (ServletToolInfo)info;
 
                 if (ViewContext.REQUEST.equalsIgnoreCase(sti.getScope()))
                 {
                     requestToolInfo.add(sti);
                     return;
                 }
                 else if (ViewContext.SESSION.equalsIgnoreCase(sti.getScope()))
                 {
                     sessionToolInfo.add(sti);
                     return;
                 }
                 else if (ViewContext.APPLICATION.equalsIgnoreCase(sti.getScope()))
                 {
                     /* add application scoped tools to appTools and
                      * initialize them with the ServletContext */
                     appTools.put(sti.getKey(), sti.getInstance(servletContext));
                     return;
                 }
                 else
                 {
                     LOG.warn("Unknown scope '" + sti.getScope() + "' - " +
                             sti.getKey() + " will be request scoped.");
 
                     //default is request scope
                     requestToolInfo.add(info);
                 }
             }
             else
             {
                 //default is request scope
                 requestToolInfo.add(info);
             }
         }
     }
 
     /**
      * Overrides XMLToolboxManager to put data into appTools map
      */
     public void addData(ToolInfo info)
     {
         if (validateToolInfo(info))
         {
             appTools.put(info.getKey(), info.getInstance(null));
         }
     }
 
     /**
      * Overrides XMLToolboxManager to handle the separate
      * scopes.
      *
      * Application scope tools were initialized when the toolbox was loaded.
      * Session scope tools are initialized once per session and stored in a
      * map in the session attributes.
      * Request scope tools are initialized on every request.
      *
      * @param initData the {@link ViewContext} for the current servlet request
      */
     public Map getToolbox(Object initData)
     {
         //we know the initData is a ViewContext
         ViewContext ctx = (ViewContext)initData;
         String requestPath = ServletUtils.getPath(ctx.getRequest());
 
         //create the toolbox map with the application tools in it
         Map toolbox = new HashMap(appTools);
 
         if (!sessionToolInfo.isEmpty())
         {
             HttpSession session = ctx.getRequest().getSession(createSession);
             if (session != null)
             {
                 // allow only one thread per session at a time
                 synchronized(getMutex(session))
                 {
                     // get the session tools
                     Map stmap = (Map)session.getAttribute(SESSION_TOOLS_KEY);
                     if (stmap == null)
                     {
                         // init and store session tools map
                         stmap = new HashMap(sessionToolInfo.size());
                         Iterator i = sessionToolInfo.iterator();
                         while(i.hasNext())
                         {
                             ServletToolInfo sti = (ServletToolInfo)i.next();
                             stmap.put(sti.getKey(), sti.getInstance(ctx));
                         }
                         session.setAttribute(SESSION_TOOLS_KEY, stmap);
                     }
                     // add them to the toolbox
                     toolbox.putAll(stmap);
                 }
             }
         }
 
         //add and initialize request tools
         Iterator i = requestToolInfo.iterator();
         while(i.hasNext())
         {
             ToolInfo info = (ToolInfo)i.next();
             if (info instanceof ServletToolInfo)
             {
                 ServletToolInfo sti = (ServletToolInfo)info;
                 if (!sti.allowsRequestPath(requestPath))
                 {
                     continue;
                 }
             }
             toolbox.put(info.getKey(), info.getInstance(ctx));
         }
 
         return toolbox;
     }
 
 
     /**
      * Returns a mutex (lock object) unique to the specified session
      * to allow for reliable synchronization on the session.
      */
     protected Object getMutex(HttpSession session)
     {
         // yes, this uses double-checked locking, but it is safe here
         // since partial initialization of the lock is not an issue
         Object lock = session.getAttribute("session.mutex");
         if (lock == null)
         {
             // one thread per toolbox manager at a time
             synchronized(this)
             {
                 // in case another thread already came thru
                 lock = session.getAttribute("session.mutex");
                 if (lock == null)
                 {
                     // use a Boolean because it is serializable and small
                     lock = new Boolean(true);
                     session.setAttribute("session.mutex", lock);
                 }
             }
         }
         return lock;
     }
 
 }