001// Copyright 2010-2013 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007// http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry5.internal.services;
016
017import org.apache.tapestry5.commons.util.CollectionFactory;
018import org.apache.tapestry5.commons.util.ExceptionUtils;
019import org.apache.tapestry5.http.services.RequestGlobals;
020import org.apache.tapestry5.internal.InternalConstants;
021import org.apache.tapestry5.internal.structure.Page;
022import org.apache.tapestry5.ioc.ScopeConstants;
023import org.apache.tapestry5.ioc.annotations.PostInjection;
024import org.apache.tapestry5.ioc.annotations.Scope;
025import org.apache.tapestry5.ioc.services.PerthreadManager;
026import org.apache.tapestry5.services.ComponentClassResolver;
027import org.slf4j.Logger;
028
029import java.util.Map;
030
031/**
032 * In Tapestry 5.1, the implementation of this worked with the page pool (a pool of page instances, reserved
033 * to individual requests/threads). Page pooling was deprecated in 5.2 and removed in 5.3.
034 *
035 * @since 5.2
036 */
037@Scope(ScopeConstants.PERTHREAD)
038public class RequestPageCacheImpl implements RequestPageCache, Runnable
039{
040    private final Logger logger;
041
042    private final ComponentClassResolver resolver;
043
044    private final PageSource pageSource;
045
046    private final RequestGlobals requestGlobals;
047
048    private final Map<String, Page> cache = CollectionFactory.newMap();
049
050    public RequestPageCacheImpl(Logger logger, ComponentClassResolver resolver, PageSource pageSource, RequestGlobals requestGlobals)
051    {
052        this.logger = logger;
053        this.resolver = resolver;
054        this.pageSource = pageSource;
055        this.requestGlobals = requestGlobals;
056    }
057
058    @PostInjection
059    public void listenForThreadCleanup(PerthreadManager perthreadManager)
060    {
061        perthreadManager.addThreadCleanupCallback(this);
062    }
063
064    public void run()
065    {
066        for (Page page : cache.values())
067        {
068            try
069            {
070                page.detached();
071            } catch (Throwable t)
072            {
073                logger.error("Error detaching page {}: {}", page, ExceptionUtils.toMessage(t), t);
074            }
075        }
076    }
077
078    public Page get(String pageName)
079    {
080        String canonical = resolver.canonicalizePageName(pageName);
081
082        Page page = cache.get(canonical);
083
084        if (page == null)
085        {
086            page = pageSource.getPage(canonical);
087
088            try
089            {
090                page.attached();
091            } catch (Throwable t)
092            {
093                throw new RuntimeException(String.format("Unable to attach page %s: %s", canonical,
094                        ExceptionUtils.toMessage(t)), t);
095            }
096
097            cache.put(canonical, page);
098        }
099
100        // A bit of a hack but whatever.
101        if (canonical.equals(requestGlobals.getActivePageName()))
102        {
103            requestGlobals.getRequest().setAttribute(InternalConstants.ACTIVE_PAGE_LOADED, true);
104        }
105
106        return page;
107    }
108}