com.googlecode.sarasvati.hib.HibEngine.java Source code

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/*
This file is part of Sarasvati.
    
Sarasvati is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation, either version 3 of the
License, or (at your option) any later version.
    
Sarasvati is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.
    
You should have received a copy of the GNU Lesser General Public
License along with Sarasvati.  If not, see <http://www.gnu.org/licenses/>.
    
Copyright 2008 Paul Lorenz
*/

package com.googlecode.sarasvati.hib;

import java.util.List;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.cfg.Configuration;

import com.googlecode.sarasvati.ArcToken;
import com.googlecode.sarasvati.DelayedTokenScheduler;
import com.googlecode.sarasvati.GraphProcess;
import com.googlecode.sarasvati.NodeToken;
import com.googlecode.sarasvati.event.DefaultExecutionEventQueue;
import com.googlecode.sarasvati.event.ExecutionEventType;
import com.googlecode.sarasvati.event.ExecutionListener;
import com.googlecode.sarasvati.impl.BaseEngine;
import com.googlecode.sarasvati.impl.TimerBasedDelayedTokenScheduler;
import com.googlecode.sarasvati.load.GraphLoader;
import com.googlecode.sarasvati.load.GraphLoaderImpl;
import com.googlecode.sarasvati.load.GraphValidator;

public class HibEngine extends BaseEngine {
    protected Session session;
    protected HibGraphFactory factory;
    protected HibGraphRepository repository;

    /**
     * This constructor can be used in cases when the session will be set in later
     * or when performing operations that don't require a session, such as adding
     * global execution listeners. The HibEngine is created with the default
     * application context.
     * <p>
     * Each application context has it's own set of global listeners.
     *
     * This allows different applications running the same JVM to
     * have different sets of listeners without having to add
     * them at the process level.
     */
    public HibEngine() {
        super(DEFAULT_APPLICATION_CONTEXT);
    }

    /**
     * This constructor can be used in cases when the session will be set in later
     * or when performing operations that don't require a session, such as adding
     * global execution listeners. The HibEngine is created with the given
     * application context.
     * <p>
     * Each application context has it's own set of global listeners.
     *
     * This allows different applications running the same JVM to
     * have different sets of listeners without having to add
     * them at the process level.
     */
    public HibEngine(final String applicationContext) {
        super(applicationContext);
    }

    /**
     * Creates a new HibEngine with the default application context.
     * <p>
     * Each application context has it's own set of global listeners.
     *
     * This allows different applications running the same JVM to
     * have different sets of listeners without having to add
     * them at the process level.
     *
     * @param session The hibernate session.
     */
    public HibEngine(final Session session) {
        this(DEFAULT_APPLICATION_CONTEXT, session);
    }

    /**
     * Creates a new HibEngine with the given application context.
     * <p>
     * Each application context has it's own set of global listeners.
     *
     * This allows different applications running the same JVM to
     * have different sets of listeners without having to add
     * them at the process level.
     *
     * @param session The hibernate session.
     */
    public HibEngine(final String applicationContext, final Session session) {
        super(applicationContext);
        this.session = session;
        this.factory = new HibGraphFactory(session);
        this.repository = new HibGraphRepository(session);
    }

    public Session getSession() {
        return session;
    }

    public void setSession(final Session session) {
        this.session = session;
        this.factory = new HibGraphFactory(session);
        this.repository = new HibGraphRepository(session);
    }

    @Override
    public HibGraphRepository getRepository() {
        return repository;
    }

    @Override
    public HibGraphFactory getFactory() {
        return factory;
    }

    @Override
    public GraphLoader<HibGraph> getLoader() {
        return getLoader(null);
    }

    @Override
    public GraphLoader<HibGraph> getLoader(final GraphValidator validator) {
        return new GraphLoaderImpl<HibGraph>(getFactory(), getRepository(), validator);
    }

    @Override
    public void addExecutionListener(final GraphProcess process,
            final Class<? extends ExecutionListener> listenerClass, final ExecutionEventType... eventTypes) {
        if (eventTypes == null || eventTypes.length == 0 || listenerClass == null) {
            return;
        }

        int eventTypeMask = 0;

        for (final ExecutionEventType eventType : eventTypes) {
            if (eventType != null) {
                eventTypeMask |= eventType.getEventType();
            }
        }

        if (eventTypeMask != 0) {
            final String type = listenerClass.getName();
            boolean updated = false;
            for (final HibProcessListener hibListener : ((HibGraphProcess) process).getListeners()) {
                if (type.equals(hibListener.getType())) {
                    hibListener.setEventTypeMask(eventTypeMask);
                    updated = true;
                    break;
                }
            }

            if (!updated) {
                final HibProcessListener hibListener = new HibProcessListener(type, eventTypeMask, process);
                session.save(hibListener);
            }
        }

        super.addExecutionListener(process, listenerClass, eventTypes);
    }

    @Override
    public void removeExecutionListener(final GraphProcess process,
            final Class<? extends ExecutionListener> listenerClass, final ExecutionEventType... eventTypes) {
        if (listenerClass == null) {
            return;
        }

        final int removeMask = ExecutionEventType.invertMask(ExecutionEventType.toMask(eventTypes));

        for (final HibProcessListener hibListener : ((HibGraphProcess) process).getListeners()) {
            if (listenerClass.getName().equals(hibListener.getType())) {
                if (eventTypes == null || eventTypes.length == 0) {
                    session.delete(hibListener);
                } else {
                    final int newMask = hibListener.getEventTypeMask() & removeMask;
                    if (newMask == 0) {
                        session.delete(hibListener);
                    } else {
                        hibListener.setEventTypeMask(newMask);
                    }
                }
            }
        }

        super.removeExecutionListener(process, listenerClass, eventTypes);
    }

    @Override
    public HibEngine newEngine() {
        final HibEngine engine = new HibEngine(applicationContext);

        engine.session = session;
        engine.factory = factory;
        engine.repository = repository;

        return engine;
    }

    @SuppressWarnings("unchecked")
    public List<ArcToken> getActiveArcTokens(final HibTokenSet tokenSet) {
        final String hql = "select token from HibArcToken token inner join token.tokenSetMemberships as setMember "
                + "where token.completeDate is null and setMember.tokenSet = :tokenSet";
        final Query query = session.createQuery(hql).setEntity("tokenSet", tokenSet);
        return query.list();
    }

    @SuppressWarnings("unchecked")
    public List<NodeToken> getActiveNodeTokens(final HibTokenSet tokenSet) {
        final String hql = "select token from HibNodeToken token inner join token.tokenSetMemberships as setMember "
                + "where token.completeDate is null and setMember.tokenSet = :tokenSet";
        final Query query = session.createQuery(hql).setEntity("tokenSet", tokenSet);
        return query.list();
    }

    /**
     * @see com.googlecode.sarasvati.Engine#getDelayedTokenScheduler()
     */
    @Override
    public DelayedTokenScheduler getDelayedTokenScheduler() {
        return TimerBasedDelayedTokenScheduler.newDelayedTokenScheduler(
                new HibEngineFactory(session.getSessionFactory(), getApplicationContext()));
    }

    /**
     * Ensures that the given node token is the latest from the current session
     *
     * @see com.googlecode.sarasvati.impl.BaseEngine#reevaluateDelayedToken(com.googlecode.sarasvati.NodeToken)
     */
    @Override
    public void reevaluateDelayedToken(final NodeToken token) {
        if (token instanceof HibNodeToken) {
            HibNodeToken hibNodeToken = (HibNodeToken) token;
            hibNodeToken = getRepository().findNodeToken(hibNodeToken.getId());
            super.reevaluateDelayedToken(hibNodeToken);
        } else {
            super.reevaluateDelayedToken(token);
        }
    }

    public static void addToConfiguration(final Configuration config, final boolean enableCaching) {
        config.addAnnotatedClass(HibArc.class);
        config.addAnnotatedClass(HibArcToken.class);
        config.addAnnotatedClass(HibGraph.class);
        config.addAnnotatedClass(HibGraphListener.class);
        config.addAnnotatedClass(HibProcessListener.class);
        config.addAnnotatedClass(HibNode.class);
        config.addAnnotatedClass(HibNodeRef.class);
        config.addAnnotatedClass(HibNodeToken.class);
        config.addAnnotatedClass(HibGraphProcess.class);
        config.addAnnotatedClass(HibPropertyNode.class);
        config.addAnnotatedClass(HibCustomNodeWrapper.class);
        config.addAnnotatedClass(HibTokenSet.class);
        config.addAnnotatedClass(HibArcTokenSetMember.class);
        config.addAnnotatedClass(HibNodeTokenSetMember.class);
        config.addAnnotatedClass(HibNodeType.class);
        config.addAnnotatedClass(HibTokenSetMemberAttribute.class);
        config.addAnnotatedClass(HibExternal.class);

        if (enableCaching) {
            config.setCacheConcurrencyStrategy(HibGraph.class.getName(), "read-write");
            config.setCollectionCacheConcurrencyStrategy(HibGraph.class.getName() + ".nodes", "read-write");
            config.setCollectionCacheConcurrencyStrategy(HibGraph.class.getName() + ".arcs", "read-write");
            config.setCollectionCacheConcurrencyStrategy(HibGraph.class.getName() + ".listeners", "read-write");

            config.setCacheConcurrencyStrategy(HibGraphListener.class.getName(), "read-write");

            config.setCacheConcurrencyStrategy(HibNode.class.getName(), "read-write");
            config.setCacheConcurrencyStrategy(HibNodeRef.class.getName(), "read-write");
            config.setCacheConcurrencyStrategy(HibArc.class.getName(), "read-write");
            config.setCacheConcurrencyStrategy(HibExternal.class.getName(), "read-write");

            config.setCacheConcurrencyStrategy(HibGraphProcess.class.getName(), "read-write");
            config.setCollectionCacheConcurrencyStrategy(HibGraphProcess.class.getName() + ".listeners",
                    "read-write");
            config.setCollectionCacheConcurrencyStrategy(HibGraphProcess.class.getName() + ".activeArcTokens",
                    "read-write");
            config.setCollectionCacheConcurrencyStrategy(HibGraphProcess.class.getName() + ".activeNodeTokens",
                    "read-write");
            config.setCollectionCacheConcurrencyStrategy(HibGraphProcess.class.getName() + ".executionQueue",
                    "read-write");

            config.setCacheConcurrencyStrategy(HibProcessListener.class.getName(), "read-write");
            config.setCacheConcurrencyStrategy(HibNodeToken.class.getName(), "read-write");
            config.setCacheConcurrencyStrategy(HibArcToken.class.getName(), "read-write");
        }
    }

    /**
     * Provides a subclass to override which execution event listeners are added to
     * new global queues. By default this adds the listeners from {@link BaseEngine}
     * as well as the following listeners:
     * <ul>
     *  <li>{@link TokenSetDeadEndListener}</li>
     * </ul>
     *
     * @param queue The new global queue
     */
    @Override
    protected void contributeGlobalListeners(final DefaultExecutionEventQueue queue) {
        super.contributeGlobalListeners(queue);
        queue.addListener(new TokenSetDeadEndListener(), ExecutionEventType.ARC_TOKEN_INCOMPLETE_JOIN,
                ExecutionEventType.NODE_TOKEN_COMPLETED);
    }
}