freemarker.ext.servlet.AllHttpScopesHashModel Maven / Gradle / Ivy
Go to download
Google App Engine compliant variation of FreeMarker.
FreeMarker is a "template engine"; a generic tool to generate text output based on templates.
/*
* Copyright (c) 2003 The Visigoth Software Society. 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 acknowledgement:
* "This product includes software developed by the
* Visigoth Software Society (http://www.visigoths.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. Neither the name "FreeMarker", "Visigoth", nor any of the names of the
* project contributors may be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact [email protected].
*
* 5. Products derived from this software may not be called "FreeMarker" or "Visigoth"
* nor may "FreeMarker" or "Visigoth" appear in their names
* without prior written permission of the Visigoth Software Society.
*
* 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 VISIGOTH SOFTWARE SOCIETY 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 Visigoth Software Society. For more
* information on the Visigoth Software Society, please see
* http://www.visigoths.org/
*/
package freemarker.ext.servlet;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import freemarker.template.ObjectWrapper;
import freemarker.template.SimpleHash;
import freemarker.template.TemplateModel;
import freemarker.template.TemplateModelException;
/**
* An extension of SimpleHash that looks up keys in the hash, then in the
* request, session, and servlet context scopes. Makes "Application", "Session"
* and "Request" keys largely obsolete, however we keep them for backward
* compatibility (also, "Request" is required for proper operation of JSP
* taglibs).
* It is on purpose that we didn't override keys and values
* methods. That way, only those variables assigned into the hash directly by a
* subclass of FreemarkerServlet that overrides
* preTemplateProcess) are discovered as "page" variables by the FM
* JSP PageContext implementation.
* @author Attila Szegedi
* @version $Id: AllHttpScopesHashModel.java,v 1.5.4.1 2006/04/26 12:22:07 szegedia Exp $
*/
public class AllHttpScopesHashModel extends SimpleHash
{
private final ServletContext context;
private final HttpServletRequest request;
private final Map unlistedModels = new HashMap();
/**
* Creates a new instance of AllHttpScopesHashModel for handling a single
* HTTP servlet request.
* @param wrapper the object wrapper to use
* @param context the servlet context of the web application
* @param request the HTTP servlet request being processed
*/
public AllHttpScopesHashModel(ObjectWrapper wrapper,
ServletContext context, HttpServletRequest request) {
setObjectWrapper(wrapper);
this.context = context;
this.request = request;
}
/**
* Stores a model in the hash so that it doesn't show up in keys()
* and values() methods. Used to put the Application, Session,
* Request, RequestParameters and JspTaglibs objects.
* @param key the key under which the model is stored
* @param model the stored model
*/
public void putUnlistedModel(String key, TemplateModel model)
{
unlistedModels.put(key, model);
}
public TemplateModel get(String key) throws TemplateModelException {
// Lookup in page scope
TemplateModel model = super.get(key);
if(model != null) {
return model;
}
// Look in unlisted models
model = (TemplateModel)unlistedModels.get(key);
if(model != null) {
return model;
}
// Lookup in request scope
Object obj = request.getAttribute(key);
if(obj != null) {
return wrap(obj);
}
// Lookup in session scope
HttpSession session = request.getSession(false);
if(session != null) {
obj = session.getAttribute(key);
if(obj != null) {
return wrap(obj);
}
}
// Lookup in application scope
obj = context.getAttribute(key);
if(obj != null) {
return wrap(obj);
}
// return wrapper's null object (probably null).
return wrap(null);
}
}