cvs commit: jakarta-velocity/src/java/org/apache/velocity InternalContext.java

[ge...@locus.apache.org]

geirm       00/12/12 15:41:37

  Added:       src/java/org/apache/velocity InternalContext.java
  Log:
  Helps formalize the idea of using the context as a thread-safe storage unit for parsing and init-ing.  Moved the template-name stuff from Context, and added support for 'node-local context data introspection caching', to coin a phrase.
  Context now extends this.
  
  Revision  Changes    Path
  1.1                  jakarta-velocity/src/java/org/apache/velocity/InternalContext.java
  
  Index: InternalContext.java
  ===================================================================
  /*
   * The Apache Software License, Version 1.1
   *
   * Copyright (c) 2000 The Apache Software Foundation.  All rights
   * reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. The end-user documentation included with the redistribution, if
   *    any, must include the following acknowlegement:
   *       "This product includes software developed by the
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowlegement may appear in the software itself,
   *    if and wherever such third-party acknowlegements normally appear.
   *
   * 4. The names "The Jakarta Project", "Velocity", and "Apache Software
   *    Foundation" must not be used to endorse or promote products derived
   *    from this software without prior written permission. For written
   *    permission, please contact apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache"
   *    nor may "Apache" appear in their names without prior written
   *    permission of the Apache Group.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   */
  
  package org.apache.velocity;
  
  import java.util.Hashtable;
  import java.io.Serializable;
  
  import org.apache.velocity.util.introspection.IntrospectionCacheData;
  
  /**
   *  class to encapsulate the 'stuff' for internal operation of velocity.  
   *  We use the context as a thread-safe storage : we take advantage of the
   *  fact that it's a visitor  of sorts  to all nodes (that matter) of the 
   *  AST during init() and render().
   *  Currently, it carries the template name for namespace
   *  support, as well as node-local context data introspection caching.
   *
   * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
   * @version $Id: InternalContext.java,v 1.1 2000/12/12 23:41:36 geirm Exp $
   */
  
  public class InternalContext implements Serializable
  {
      /**
       *  cache for node/context specific introspection information
       */
      private Hashtable introspectionCache = new Hashtable();
      
      /**
       *  Current template name.
       */
      private String strCurrentTemplate = "<undef>";
  
      /**
       *  set the current template name
       *
       *  @param s current template name to set
       */
      public void setCurrentTemplateName( String s )
      {
          strCurrentTemplate = s;
          return;
      }
      
      /**
       *  get the current template name
       *
       *  @return String current template name
       */
      public String getCurrentTemplateName()
      {
          return strCurrentTemplate;
      }
  
      /**
       *  returns an IntrospectionCache Data (@see IntrospectionCacheData)
       *  object if exists for the key
       *
       *  @param key  key to find in cache
       *  @return cache object
       */
      public IntrospectionCacheData icacheGet( Object key )
      {
          return ( IntrospectionCacheData ) introspectionCache.get( key );
      }
       
      /**
       *  places an IntrospectionCache Data (@see IntrospectionCacheData)
       *  element in the cache for specified key
       *
       *  @param key  key 
       *  @param o  IntrospectionCacheData object to place in cache
       */
      public void icachePut( Object key, IntrospectionCacheData o )
      {
          introspectionCache.put( key, o );
      }    
  }