001/*
002 * (C) Copyright 2006-2011 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     bstefanescu
018 */
019package org.nuxeo.ecm.webengine.jaxrs.session.impl;
020
021import java.util.concurrent.locks.ReentrantLock;
022
023import javax.servlet.http.HttpServletRequest;
024import javax.servlet.http.HttpSession;
025import javax.servlet.http.HttpSessionBindingEvent;
026import javax.servlet.http.HttpSessionBindingListener;
027
028import org.apache.commons.logging.Log;
029import org.apache.commons.logging.LogFactory;
030import org.nuxeo.ecm.core.api.CoreSession;
031import org.nuxeo.ecm.webengine.jaxrs.session.CoreSessionProvider;
032import org.nuxeo.ecm.webengine.jaxrs.session.SessionFactory;
033import org.nuxeo.ecm.webengine.jaxrs.session.SessionRef;
034import org.nuxeo.ecm.webengine.jaxrs.session.impl.PerSessionCoreProvider.Ref;
035import org.nuxeo.runtime.api.Framework;
036
037/**
038 * @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a>
039 */
040public class PerSessionCoreProvider extends CoreSessionProvider<Ref> implements HttpSessionBindingListener {
041
042    private static final Log log = LogFactory.getLog(PerSessionCoreProvider.class);
043
044    public static class Ref implements SessionRef {
045        protected CoreSession session;
046
047        protected ReentrantLock lock;
048
049        public Ref(CoreSession session) {
050            this.session = session;
051            this.lock = new ReentrantLock();
052        }
053
054        @Override
055        public CoreSession get() {
056            lock.lock();
057            return session;
058        }
059
060        @Override
061        public void unget() {
062            // unlock only if the current thread holds the lock otherwise ignore.
063            try {
064                lock.unlock();
065            } catch (IllegalMonitorStateException e) {
066                // do nothing
067            }
068        }
069
070        @Override
071        public void destroy() {
072            session = null;
073            lock = null;
074        }
075
076    }
077
078    public static synchronized void install(HttpServletRequest request) {
079        HttpSession s = request.getSession(true);
080        if (s.getAttribute(SessionFactory.SESSION_FACTORY_KEY) == null) {
081            s.setAttribute(SessionFactory.SESSION_FACTORY_KEY, new PerSessionCoreProvider());
082        }
083    }
084
085    @Override
086    protected Ref createSessionRef(CoreSession session) {
087        return new Ref(session);
088    }
089
090    @Override
091    public void onRequestDone(HttpServletRequest request) {
092        // unlock sessions if any was locked
093        for (SessionRef ref : getSessions()) {
094            ref.unget();
095        }
096    }
097
098    @Override
099    public void valueBound(HttpSessionBindingEvent event) {
100        // do nothing
101    }
102
103    @Override
104    public void valueUnbound(HttpSessionBindingEvent event) {
105        // destroy all sessions
106        if (!hasSessions()) {
107            destroy();
108            return;
109        }
110
111        Framework.doPrivileged(this::destroy);
112    }
113
114    @Override
115    public synchronized SessionRef[] getSessions() {
116        return super.getSessions();
117    }
118
119    @Override
120    public synchronized SessionRef getSessionRef(HttpServletRequest request, String repoName) {
121        return super.getSessionRef(request, repoName);
122    }
123
124    @Override
125    public synchronized boolean hasSessions() {
126        return super.hasSessions();
127    }
128
129    @Override
130    protected synchronized void destroy() {
131        super.destroy();
132    }
133
134}