Application: gvSIG desktop

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright (C) 2007-2013 gvSIG Association.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 3

 * of the License, or (at your option) any later version.

 *

 * This program 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 General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 * For any additional information, do not hesitate to contact us

 * at info AT gvsig.com, or visit our website www.gvsig.com.

 */

package org.gvsig.fmap.dal.feature.impl;

import java.io.File;

import java.util.ArrayList;

import java.util.List;

import org.cresques.Messages;

import org.gvsig.fmap.dal.DataStoreNotification;

import org.gvsig.fmap.dal.DataTypes;

import org.gvsig.fmap.dal.exception.DataException;

import org.gvsig.fmap.dal.exception.InitializeException;

import org.gvsig.fmap.dal.feature.Feature;

import org.gvsig.fmap.dal.feature.FeatureAttributeDescriptor;

import org.gvsig.fmap.dal.feature.FeatureSet;

import org.gvsig.fmap.dal.feature.FeatureStore;

import org.gvsig.fmap.dal.feature.FeatureStoreNotification;

import org.gvsig.fmap.dal.feature.FeatureType;

import org.gvsig.fmap.dal.feature.exception.FeatureIndexException;

import org.gvsig.fmap.dal.feature.exception.FeatureIndexOperationException;

import org.gvsig.fmap.dal.feature.exception.InvalidFeatureIndexException;

import org.gvsig.fmap.dal.feature.spi.DefaultLongList;

import org.gvsig.fmap.dal.feature.spi.FeatureReferenceProviderServices;

import org.gvsig.fmap.dal.feature.spi.FeatureStoreProviderServices;

import org.gvsig.fmap.dal.feature.spi.index.FeatureIndexProvider;

import org.gvsig.fmap.dal.feature.spi.index.FeatureIndexProviderServices;

import org.gvsig.tools.dispose.DisposableIterator;

import org.gvsig.tools.dispose.DisposeUtils;

import org.gvsig.tools.dispose.impl.AbstractDisposable;

import org.gvsig.tools.exception.BaseException;

import org.gvsig.tools.observer.Observer;

import org.gvsig.tools.observer.WeakReferencingObservable;

import org.gvsig.tools.observer.impl.DelegateWeakReferencingObservable;

import org.gvsig.tools.task.AbstractMonitorableTask;

import org.gvsig.tools.task.CancellableTask;

import org.gvsig.tools.task.MonitorableTask;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

/**

 * Default feature index provider services.

 * 

 * @author gvSIG team

 */

public class DefaultFeatureIndex extends AbstractDisposable implements

    FeatureIndexProviderServices,

    WeakReferencingObservable {

    private static final Logger LOG = LoggerFactory

        .getLogger(DefaultFeatureIndex.class);

    private final FeatureStoreProviderServices featureStore;

    private final FeatureType featureType;

    private final String attributeName;

    private final String indexName;

    private final int dataType;

    private final FeatureIndexProvider indexProvider;

    private List attributeNames;

    private Object featureOperationTaskLock = new Object();

    private FeatureIndexOperationTask featureIndexTask;

    private boolean valid = true;

    private DelegateWeakReferencingObservable observable =

        new DelegateWeakReferencingObservable(this);

    public DefaultFeatureIndex(FeatureStoreProviderServices featureStore,

        FeatureType featureType, FeatureIndexProvider indexProvider,

        String attributeName, String indexName) {

        if (featureStore == null) {

            throw new IllegalArgumentException("featureStore cannot be null.");

        }

        if (featureType == null) {

            throw new IllegalArgumentException("featureType cannot be null.");

        }

        if (attributeName == null) {

            throw new IllegalArgumentException("attributeName cannot be null.");

        }

        if (indexName == null) {

            throw new IllegalArgumentException("indexName cannot be null.");

        }

        // FIXME Esto debe ir al provider

        if (featureStore.getProvider().getOIDType() != DataTypes.INT

            && featureStore.getProvider().getOIDType() != DataTypes.LONG) {

            throw new IllegalArgumentException();

        }

        FeatureAttributeDescriptor attr =

            featureType.getAttributeDescriptor(attributeName);

        if (attr == null) {

            throw new IllegalArgumentException("Attribute " + attributeName

                + " not found in FeatureType " + featureType.toString());

        }

        this.featureStore = featureStore;

        this.featureType = featureType;

        this.attributeName = attributeName;

        this.indexName = indexName;

        this.dataType = attr.getType();

        this.indexProvider = indexProvider;

        attributeNames = new ArrayList();

        attributeNames.add(attributeName);

    }

    public final FeatureAttributeDescriptor getFeatureAttributeDescriptor() {

        return featureType.getAttributeDescriptor(attributeName);

    }

    public final FeatureStoreProviderServices getFeatureStoreProviderServices() {

        return featureStore;

    }

    public final FeatureType getFeatureType() {

        return featureType;

    }

    public final String getAttributeName() {

        return attributeName;

    }

    public final int getDataType() {

        return dataType;

    }

    /**

     * {@link MonitorableTask} and {@link CancellableTask} to perform long

     * operations on the index: filling and inserting or deleting a feature set.

     * 

     * @author gvSIG Team

     * @version $Id$

     */

    private static class FeatureIndexOperationTask extends

        AbstractMonitorableTask {

        private final DefaultFeatureIndex index;

        public static final int OP_FILL = 0;

        public static final int OP_INSERT_FSET = 1;

        public static final int OP_DELETE_FSET = 2;

        private static final String[] OP_NAMES = { //

            Messages.getText("filling_index"), // OP_FILL

                Messages.getText("updating_index"), // OP_INSERT_FSET

                Messages.getText("updating_index"), // OP_DELETE_FSET

            };

        private final int operation;

        private final FeatureSet data;

        private final Observer operationObserver;

        private final FeatureStore store;

        /**

         * Creates a new {@link FeatureIndexOperationTask}

         * 

         * @param index

         *            to operate on

         * @param store

         *            to index data from

         * @param operation

         *            to perform: {@link #OP_FILL}, {@link #OP_INSERT_FSET} or

         *            {@link #OP_DELETE_FSET}

         * @param data

         *            feature set to insert or delete in the insert or delete

         *            operations

         * @param operationObserver

         *            to be notified when the operation starts, finishes, is

         *            cancelled or has finished with errors

         */

        protected FeatureIndexOperationTask(DefaultFeatureIndex index,

            FeatureStore store, int operation, FeatureSet data,

            Observer operationObserver) {

            super(OP_NAMES[operation]);

            this.index = index;

            this.store = store;

            this.operation = operation;

            this.data = data;

            this.operationObserver = operationObserver;

            setDaemon(true);

            setPriority(MIN_PRIORITY);

        }

        public void run() {

            try {

                switch (operation) {

                case OP_FILL:

                    notify(FeatureStoreNotification.INDEX_FILLING_STARTED);

                    clearAndFill();

                    break;

                case OP_INSERT_FSET:

                    notify(FeatureStoreNotification.INDEX_FILLING_STARTED);

                    insert(data);

                    break;

                case OP_DELETE_FSET:

                    notify(FeatureStoreNotification.INDEX_FILLING_STARTED);

                    delete(data);

                    break;

                }

            } catch (Exception e) {

                Exception fioex =

                    new FeatureIndexOperationException(index,

                        OP_NAMES[operation], e);

                notify(FeatureStoreNotification.INDEX_FILLING_ERROR, fioex);

                throw new RuntimeException(fioex);

            } finally {

                index.removeTask(this);

            }

        }

        /**

         * Clears the index data and fills it again.

         */

        private void clearAndFill() throws DataException {

            FeatureSet set = null;

            try {

                synchronized (index) {

                    set = store.getFeatureSet();

                    if (isCancellationRequested()) {

                        cancel();

                        return;

                    }

                    index.clear();

                    if (isCancellationRequested()) {

                        cancel();

                        return;

                    }

                    insert(set);

                    index.setValid(true);

                }

            } catch (IllegalStateException e) {

                    // The feature store has entered in editing or 

                    // append mode again, cancel indexing.

                    cancel();

            } finally {

                DisposeUtils.dispose(set);

            }

        }

        private void insert(FeatureSet data) throws DataException {

            DisposableIterator it = null;

            long counter = 0;

            try {

                it = data.fastIterator();

                synchronized (index) {

                    taskStatus.setRangeOfValues(0, data.getSize());

                    taskStatus.add();

                    while (it.hasNext()) {

                        if (isCancellationRequested()) {

                            index.clear();

                            cancel();

                            return;

                        }

                        Feature feat = (Feature) it.next();

                        index.insert(feat);

                        taskStatus.setCurValue(counter++);

                    }

                    notify(FeatureStoreNotification.INDEX_FILLING_SUCCESS);

                }

                taskStatus.terminate();

            } catch (IllegalStateException e) {

                    // The feature store has entered in editing or 

                    // append mode again, cancel indexing.

                    taskStatus.cancel();

            } catch (RuntimeException e) {

                taskStatus.abort();

                throw e;

            } catch (DataException e) {

                taskStatus.abort();

                throw e;

            } finally {

                DisposeUtils.dispose(it);

                taskStatus.remove();

            }

        }

        private void delete(FeatureSet data) throws FeatureIndexException {

            DisposableIterator it = null;

            try {

                it = data.fastIterator();

                synchronized (index) {

                    while (it.hasNext()) {

                        if (isCancellationRequested()) {

                            cancel();

                            return;

                        }

                        Feature feat = (Feature) it.next();

                        index.delete(feat);

                    }

                    notify(FeatureStoreNotification.INDEX_FILLING_SUCCESS);

                }

            } catch (DataException e) {

                throw new FeatureIndexException(e);

            } finally {

                DisposeUtils.dispose(it);

            }

        }

        private void cancel() {

            notify(FeatureStoreNotification.INDEX_FILLING_CANCELLED);

            taskStatus.cancel();

        }

        public void notifyOperationObserver(DataStoreNotification notification) {

            if (this.operationObserver != null) {

                this.operationObserver.update(index, notification);

            }

        }

        private void notify(String notificationType) {

            DataStoreNotification notification =

                new DefaultFeatureStoreNotification(store, notificationType,

                    index);

            notifyOperationObserver(notification);

            index.notifyObservers(notification);

        }

        private void notify(String notificationType, Exception exception) {

            DataStoreNotification notification =

                new DefaultFeatureStoreNotification(store, notificationType,

                    exception);

            notifyOperationObserver(notification);

            index.notifyObservers(notification);

        }

    }

    private FeatureIndexOperationTask createIndexTask(int operation,

        FeatureSet data, Observer observer) {

        synchronized (featureOperationTaskLock) {

            if (featureIndexTask != null) {

                this.featureIndexTask.cancelRequest();

                removeTask(this.featureIndexTask);

            }

            FeatureIndexOperationTask fillingTask =

                new FeatureIndexOperationTask(this,

                    featureStore.getFeatureStore(), operation, data, observer);

            this.featureIndexTask = fillingTask;

            return fillingTask;

        }

    }

    private void removeTask(FeatureIndexOperationTask task) {

        synchronized (featureOperationTaskLock) {

            // Remove if it is not null and the same task

            if (this.featureIndexTask == task) {

                featureIndexTask = null;

            }

        }

    }

    public void fill() throws FeatureIndexException {

        fill(false, null);

    }

    public void fill(boolean background, Observer observer)

        throws FeatureIndexException {

        FeatureIndexOperationTask task =

            createIndexTask(FeatureIndexOperationTask.OP_FILL, null, observer);

        if (background) {

            task.start();

        } else {

            task.run();

        }

    }

    public final void insert(FeatureSet data) throws DataException {

        if (!isValid()) {

            throw new InvalidFeatureIndexException();

        }

        FeatureIndexOperationTask task =

            createIndexTask(FeatureIndexOperationTask.OP_INSERT_FSET, data,

                null);

        task.run();

    }

    public synchronized final void insert(Feature feat) throws DataException {

        try {

                FeatureIndexProvider prov = getIndexProvider();

                Object value = feat.get(getAttributeName());

                if(prov.allowNulls() || value != null ) {

                        prov.insert(value,

                                        (FeatureReferenceProviderServices) feat.getReference());

                }

        } catch (NullPointerException e) {

            throw new IllegalArgumentException("Could not add Feature: " + feat

                + " to index " + this

                + ". It does not contain a column with name "

                + getAttributeName());

        } catch (ClassCastException e) {

            throw new IllegalArgumentException("Could not add Feature: " + feat

                + " to index " + this + ". Attribute " + getAttributeName()

                + " data type is not valid.");

        }

    }

    public final void delete(FeatureSet data) throws FeatureIndexException {

        if (!isValid()) {

            throw new InvalidFeatureIndexException();

        }

        FeatureIndexOperationTask task =

            createIndexTask(FeatureIndexOperationTask.OP_DELETE_FSET, data,

                null);

        task.run();

    }

    public synchronized final void delete(Feature feat) throws DataException {

        getIndexProvider().delete(feat.get(getAttributeName()),

            (FeatureReferenceProviderServices) feat.getReference());

    }

    private synchronized void clear() throws DataException {

        getIndexProvider().clear();

    }

    public synchronized FeatureSet getMatchFeatureSet(Object value)

        throws FeatureIndexException {

        if (!isValid()) {

            throw new InvalidFeatureIndexException();

        }

        return new IndexFeatureSet(this, new DefaultLongList(

            indexProvider.match(value)));

    }

    public synchronized FeatureSet getRangeFeatureSet(Object value1,

        Object value2) throws FeatureIndexException {

        if (!isValid()) {

            throw new InvalidFeatureIndexException();

        }

        return new IndexFeatureSet(this, new DefaultLongList(

            indexProvider.range(value1, value2)));

    }

    public synchronized FeatureSet getNearestFeatureSet(int count, Object value)

        throws FeatureIndexException {

        if (!isValid()) {

            throw new InvalidFeatureIndexException();

        }

        return new IndexFeatureSet(this, new DefaultLongList(

            indexProvider.nearest(count, value)));

    }

    public synchronized FeatureSet getNearestFeatureSet(int count,

        Object value, Object tolerance) throws FeatureIndexException {

        if (!isValid()) {

            throw new InvalidFeatureIndexException();

        }

        return new IndexFeatureSet(this, new DefaultLongList(

            indexProvider.nearest(count, value, tolerance)));

    }

    public void initialize() throws InitializeException {

        indexProvider.setFeatureIndexProviderServices(this);

        indexProvider.initialize();

    }

    public List getAttributeNames() {

        return attributeNames;

    }

    public String getNewFileName(String prefix, String sufix) {

        int n = 0;

        File file = new File(prefix + getName(), sufix);

        while (file.exists()) {

            n++;

            file = new File(prefix + getName() + n, sufix);

        }

        return file.getAbsolutePath();

    }

    public String getFileName() {

        // TODO Auto-generated method stub

        return null;

    }

    public String getTemporaryFileName() {

        // TODO Auto-generated method stub

        return null;

    }

    public FeatureIndexProvider getFeatureIndexProvider() {

        return this.indexProvider;

    }

    public boolean isFilling() {

        synchronized (featureOperationTaskLock) {

            return featureIndexTask != null;

        }

    }

    public boolean isValid() {

        synchronized (featureOperationTaskLock) {

            return !isFilling() && valid;

        }

    }

    public synchronized void waitForIndex() {

        // Nothing to do, this is just used for anyone to block until the index

        // has finished being used by a FeatureIndexOperation.

        LOG.debug("Wait finished for index: {}", this);

    }

    public void setValid(boolean valid) {

        synchronized (featureOperationTaskLock) {

            this.valid = valid;

        }

    }

    protected void doDispose() throws BaseException {

        synchronized (featureOperationTaskLock) {

            setValid(false);

            if (this.featureIndexTask != null) {

                this.featureIndexTask.cancelRequest();

                this.featureIndexTask = null;

            }

        }

        // Wait for any task until it finishes running

        synchronized (this) {

            return;

        }

    }

    public String toString() {

        return "Feature index with name" + indexName

            + ", for the FeatureType: " + featureType + ", and the attribute: "

            + attributeName;

    }

    public void notifyObservers(Object notification) {

        observable.notifyObservers(notification);

    }

    public String getName() {

        return indexName;

    }

    private FeatureIndexProvider getIndexProvider() {

        return indexProvider;

    }

    public void addObserver(Observer observer) {

        observable.addObserver(observer);

    }

    public void deleteObserver(Observer observer) {

        observable.deleteObserver(observer);

    }

    public void deleteObservers() {

        observable.deleteObservers();

    }

}