org.jactr.core.module.declarative.search.map.DefaultValueMap.java Source code

Introduction

Here is the source code for org.jactr.core.module.declarative.search.map.DefaultValueMap.java

Source

/*
 * Created on Oct 12, 2006 Copyright (C) 2001-6, Anthony Harrison anh23@pitt.edu
 * (jactr.org) This library 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 2.1 of the License,
 * or (at your option) any later version. This library 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 this
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place, Suite 330, Boston, MA 02111-1307 USA
 */
package org.jactr.core.module.declarative.search.map;

import java.util.Collection;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.locks.ReentrantReadWriteLock;

import javolution.util.FastList;
import javolution.util.FastMap;
import javolution.util.FastSet;
import javolution.util.FastTable;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class DefaultValueMap<V, I> implements IValueMap<V, I> {
    /**
     * logger definition
     */
    static public final Log LOGGER = LogFactory.getLog(DefaultValueMap.class);

    private ReentrantReadWriteLock _lock;

    private Map<V, Collection<I>> _map;

    public DefaultValueMap() {
        _lock = new ReentrantReadWriteLock();
        _map = instantiateCoreMap();
    }

    protected ReentrantReadWriteLock getLock() {
        return _lock;
    }

    protected Map<V, Collection<I>> getCoreMap() {
        return _map;
    }

    protected Collection<I> instantiateReturnCollection() {
        return new FastTable<I>();
    }

    protected Set<I> instantiateReturnSet() {
        return new FastSet<I>();
    }

    /**
     * override to provide a sorted map
     * 
     * @return
     */
    protected Map<V, Collection<I>> instantiateCoreMap() {
        FastMap<V, Collection<I>> rtn = new FastMap<V, Collection<I>>();
        //rtn.setKeyComparator(FastComparator.DIRECT);
        return rtn;
        //return new HashMap<V, Collection<I>>();
    }

    /**
     * override to change the underlying collection currently HashSet
     */
    protected Collection<I> instantiateCoreCollection(V forValue) {
        /*
         * cant be a set since a chunk can point to this value multiple times
         */
        return new FastList<I>();
        //return new HashSet<I>();
    }

    public void add(V value, I indexable) {
        if (value == null)
            throw new NullPointerException("null values are not permitted as keys");

        ReentrantReadWriteLock lock = getLock();
        try {
            lock.writeLock().lock();

            Collection<I> indexables = getCoreMap().get(value);
            if (indexables == null) {
                indexables = instantiateCoreCollection(value);
                getCoreMap().put(value, indexables);
            }
            indexables.add(indexable);
        } finally {
            lock.writeLock().unlock();
        }
    }

    public void clear(V value) {
        if (value == null)
            throw new NullPointerException("null values are not permitted as keys");

        ReentrantReadWriteLock lock = getLock();
        try {
            lock.writeLock().lock();

            Collection<I> indexables = getCoreMap().remove(value);
            if (indexables != null) {
                indexables.clear();
            }
        } finally {
            lock.writeLock().unlock();
        }
    }

    public void clear() {
        ReentrantReadWriteLock lock = getLock();
        try {
            lock.writeLock().lock();

            getCoreMap().clear();
        } finally {
            lock.writeLock().unlock();
        }
    }

    public Collection<I> get(V value) {
        if (value == null)
            throw new NullPointerException("null values are not permitted as keys");

        ReentrantReadWriteLock lock = getLock();
        Collection<I> rtn = instantiateReturnCollection();

        try {
            lock.readLock().lock();

            Collection<I> indexables = getCoreMap().get(value);
            if (indexables != null)
                rtn.addAll(indexables);
            return rtn;
        } finally {
            lock.readLock().unlock();
        }
    }

    public Collection<I> greaterThan(V value) throws UnsupportedOperationException {
        throw new UnsupportedOperationException(
                "Since natural ordering cannot be inferred, greaterThan is not implemented");
    }

    public Collection<I> lessThan(V value) throws UnsupportedOperationException {
        throw new UnsupportedOperationException(
                "Since natural ordering cannot be inferred, lessthan is not implemented");
    }

    public Collection<I> not(V value) {
        if (value == null)
            throw new NullPointerException("null values are not permitted as keys");

        Set<I> rtn = instantiateReturnSet();
        ReentrantReadWriteLock lock = getLock();
        try {
            lock.readLock().lock();

            Map<V, Collection<I>> coreMap = getCoreMap();
            for (V tmpValue : coreMap.keySet()) {
                if (!tmpValue.equals(value))
                    rtn.addAll(get(tmpValue));
            }
            return rtn;
        } finally {
            lock.readLock().unlock();
        }
    }

    public void remove(V value, I indexable) {
        if (value == null)
            throw new NullPointerException("null values are not permitted as keys");

        ReentrantReadWriteLock lock = getLock();
        try {
            lock.writeLock().lock();

            Collection<I> indexables = getCoreMap().get(value);
            if (indexables != null) {
                indexables.remove(indexable);
                if (indexables.size() == 0)
                    getCoreMap().remove(value);
            }
        } finally {
            lock.writeLock().unlock();
        }
    }

    public Collection<I> all() {
        Set<I> rtn = instantiateReturnSet();
        ReentrantReadWriteLock lock = getLock();
        try {
            lock.readLock().lock();

            for (Collection<I> values : getCoreMap().values())
                rtn.addAll(values);

            return rtn;
        } finally {
            lock.readLock().unlock();
        }
    }

}