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;

import java.util.List;

import javax.json.JsonArray;

import javax.json.JsonArrayBuilder;

import org.gvsig.expressionevaluator.Expression;

import org.gvsig.fmap.dal.DataSet;

import org.gvsig.fmap.dal.DataStore;

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

import static org.gvsig.fmap.dal.feature.DisposableFeatureSetIterable.EMPTY_DISPOSABLE_FEATURE_SET_ITERABLE;

import org.gvsig.json.Json;

import org.gvsig.tools.dispose.DisposableIterator;

import static org.gvsig.tools.dispose.DisposableIterator.EMPTY_DISPOSABLE_ITERATOR;

import org.gvsig.tools.dynobject.DynObject;

import org.gvsig.tools.dynobject.DynObjectSet;

import static org.gvsig.tools.dynobject.DynObjectSet.EMPTY_DYNOBJECTSET;

import org.gvsig.tools.exception.BaseException;

import org.gvsig.tools.util.IsEmpty;

import org.gvsig.tools.util.Size;

import org.gvsig.tools.util.Size64;

import org.gvsig.tools.visitor.IndexedVisitable;

import org.gvsig.tools.visitor.Visitor;

/**

 * A FeatureSet represents a set of {@link Feature}(s). These sets of features

 * are typically obtained directly from a {@link FeatureStore}, or through a

 * {@link FeatureQuery}.

 *

 * A FeatureSet may contain subsets of {@link Feature}(s) of different

 * {@link FeatureType}(s). It allows iterating and editing the features.

 *

 * FIXME: Actualizar javadoc

 *

 * Si el store en el que esta basado el featureset es modificado, se realiza un

 * update, insert, delete o se modifican los featuretype de este, el FeatureSet

 * quedara invalidado, y cualquier acceso a el provocara que se lance una

 * excepcion de tiempo de ejecucion ConcurrentModificationException.

 *

 * Habria que indicar que invocar al metodo accept del interface visitor

 * provocara la excepcion ConcurrentModificationException si el store a sido

 * modificado desde otro punto.

 *

 * Indicar que los metodos insert/delete/update ademas de actuar sobre el set,

 * actuan sobre el store en el que este esta basado, pero que no invalidan el

 * set sobre el que se ejecutan. No se si esto deberia hacerse mencion en esos

 * metodos o en la doc general del featureset.

 *

 */

public interface FeatureSet extends DataSet, Size64, Size, IsEmpty, IndexedVisitable, Iterable<Feature> {

    public static FeatureSet EMPTY_FEATURESET = new FeatureSet() {

        @Override

        public FeatureType getDefaultFeatureType() {

            return null;

        }

        @Override

        public List getFeatureTypes() {

            return null;

        }

        @Override

        public long getSize() throws DataException {

            return 0;

        }

        @Override

        public DisposableIterator iterator(long index) throws DataException {

            return EMPTY_DISPOSABLE_ITERATOR;

        }

        @Override

        public DisposableIterator iterator(long index, long elements) throws DataException {

            return EMPTY_DISPOSABLE_ITERATOR;

        }

        @Override

        public DisposableFeatureSetIterable iterable() {

            return EMPTY_DISPOSABLE_FEATURE_SET_ITERABLE;

        }

        @Override

        public DisposableFeatureSetIterable iterable(boolean disposeFeatureSet) {

            return EMPTY_DISPOSABLE_FEATURE_SET_ITERABLE;

        }

        @Override

        public DisposableIterator fastIterator() throws DataException {

            return EMPTY_DISPOSABLE_ITERATOR;

        }

        @Override

        public DisposableIterator fastIterator(long index) throws DataException {

            return EMPTY_DISPOSABLE_ITERATOR;

        }

        @Override

        public DisposableIterator fastIterator(long index, long elemets) throws DataException {

            return EMPTY_DISPOSABLE_ITERATOR;

        }

        @Override

        public Feature first() {

            return null;

        }

        @Override

        public void update(EditableFeature feature) throws DataException {

        }

        @Override

        public void commitChanges() throws DataException {

        }

        @Override

        public void delete(Feature feature) throws DataException {

        }

        @Override

        public void insert(EditableFeature feature) throws DataException {

        }

        @Override

        public DynObjectSet getDynObjectSet() {

            return EMPTY_DYNOBJECTSET;

        }

        @Override

        public DynObjectSet getDynObjectSet(boolean fast) {

            return EMPTY_DYNOBJECTSET;

        }

        @Override

        public void accept(Visitor visitor, long firstValueIndex) throws BaseException {

        }

        @Override

        public void accept(Visitor visitor, long firstValueIndex, long elements) throws BaseException {

        }

        @Override

        public FeatureStore getFeatureStore() {

            return null;

        }

        @Override

        public JsonArray toJSON() {

            return toJson();

        }

        @Override

        public JsonArray toJson() {

            return Json.createArrayBuilder().build();

        }

        @Override

        public JsonArrayBuilder toJsonBuilder() {

            return Json.createArrayBuilder();

        }

        @Override

        public boolean isFromStore(DataStore store) {

            return false;

        }

        @Override

        public void accept(Visitor visitor) throws BaseException {

        }

        @Override

        public void dispose() {

            // Do nothing

        }

        @Override

        public long size64() {

            return 0;

        }

        @Override

        public int size() {

            return 0;

        }

        @Override

        public boolean isEmpty() {

            return true;

        }

        @Override

        public DisposableIterator<Feature> iterator() {

            return EMPTY_DISPOSABLE_ITERATOR;

        }

        @Override

        public Expression makeFilter(int maxfeatures) {

            return null;

        }

    };

    /**

     * Returns the default {@link FeatureType} of this FeatureSet.

     *

     * @return default {@link FeatureType} in this FeatureSet.

     */

    public FeatureType getDefaultFeatureType();

    /**

     * Returns a list of the {@link FeatureType}(s) in this FeatureSet.

     *

     * @return list of the {@link FeatureType}(s) in this FeatureSet.

     */

    public List getFeatureTypes();

    /**

     * Returns the number of {@link Feature}(s) contained in this FeatureSet.

     *

     * The value returned by this method won't be accurate when the FeatureStore

     * is being edited and this set's features are modified, added or deleted.

     *

     * @return number of {@link Feature}(s) contained in this FeatureSet.

     *

     * @throws DataException

     */

    public long getSize() throws DataException;

    /**

     * Returns an iterator over the elements in this collection, in the order

     * (if any) defined when the collection was obtained.

     *

     * The iterator starts at the specified position in this collection. The

     * specified index indicates the first element that would be returned by an

     * initial call to the <tt>next</tt> method. An initial call to the

     * <tt>previous</tt> method would return the element with the specified

     * index minus one.

     *

     * <p>

     * <em>

     * <strong>NOTE:</strong> if you use this method to get the iterator, you

     * must get sure the iterator is disposed (@see

     * {@link DisposableIterator#dispose()}) in any case, even if an error

     * occurs while getting the data. It is recommended to use the

     * <code>accept</code> methods instead, which handle everything for you.

     * Take into account the accept methods may use a fast iterator to get the

     * features.

     * </em>

     * </p>

     *

     * @see #accept(org.gvsig.tools.visitor.Visitor)

     * @see #accept(org.gvsig.tools.visitor.Visitor, long)

     * @see #fastIterator()

     * @see #fastIterator(long)

     *

     * @param index index of first element to be returned from the iterator (by

     * a call to the <tt>next</tt> method).

     * @return an iterator of the elements in this collection (in proper

     * sequence), starting at the specified position in the collection.

     * @throws DataException if the index is out of range (index < 0 || index

     * > size()).

     * @deprecated use {@link #fastIterator(long)} instead

     */

    DisposableIterator iterator(long index) throws DataException;

    DisposableIterator iterator(long index, long elements) throws DataException;

    /**

     * Returns an iterator over the elements in this collection, in the order

     * (if any) defined when the collection was obtained.

     *

     * @see #accept(org.gvsig.tools.visitor.Visitor)

     * @see #accept(org.gvsig.tools.visitor.Visitor, long)

     * @see #fastIterator()

     * @see #fastIterator(long)

     *

     * @return an iterator of the elements in this collection (in proper

     * sequence).

     *

     * @deprecated use fastiterator. In next versions the signature of this

     * method will be changed to "Iterator<Feature> iterator()".

     */

    @Override

    DisposableIterator iterator();

    DisposableFeatureSetIterable iterable();

    DisposableFeatureSetIterable iterable(boolean disposeFeatureSet);

    /**

     * Returns a fast iterator over this set.

     * <p>

     * Fast in this case means that each of the elements returned may be a

     * reused or pooled object instance, so don't use it to be stored in any

     * way.

     * </p>

     * <p>

     * If you need to store one of the {@link Feature} of the iterator, use the

     * {@link Feature#getCopy()} to create a clone of the object.

     * </p>

     *

     * <p>

     * <em>

     * <strong>NOTE:</strong> if you use this method to get the iterator, you

     * must get sure the iterator is disposed (@see

     * {@link DisposableIterator#dispose()}) in any case, even if an error

     * occurs while getting the data. It is recommended to use the

     * <code>accept</code> methods instead, which handle everything for you.

     * Take into account the accept methods may use a fast iterator to get the

     * features.

     * </em>

     * </p>

     *

     * @see #accept(org.gvsig.tools.visitor.Visitor)

     * @see #accept(org.gvsig.tools.visitor.Visitor, long)

     *

     * @return an iterator over this set.

     *

     * @throws DataException

     */

    public DisposableIterator fastIterator() throws DataException;

    /**

     * Returns a fast iterator over this set, starting from the given index.

     * <p>

     * Fast in this case means that each of the elements returned may be a

     * reused or pooled object instance, so don't use it to be stored in any

     * way.

     * </p>

     * <p>

     * If you need to store one of the {@link Feature} of the iterator, use the

     * {@link Feature#getCopy()} to create a clone of the object.

     * </p>

     *

     * <p>

     * <em>

     * <strong>NOTE:</strong> if you use this method to get the iterator, you

     * must get sure the iterator is disposed (@see

     * {@link DisposableIterator#dispose()}) in any case, even if an error

     * occurs while getting the data. It is recommended to use the

     * <code>accept</code> methods instead, which handle everything for you.

     * Take into account the accept methods may use a fast iterator to get the

     * features.

     * </em>

     * </p>

     *

     * @see #accept(org.gvsig.tools.visitor.Visitor)

     * @see #accept(org.gvsig.tools.visitor.Visitor, long)

     *

     * @param index position in which the iterator is initially located.

     *

     * @return an iterator initially located at the position indicated by the

     * given index

     *

     * @throws DataException

     */

    public DisposableIterator fastIterator(long index) throws DataException;

    public DisposableIterator fastIterator(long index, long elemets) throws DataException;

    /**

     * Return the first feature of the set. If the set is empty return null.

     *

     * This not is a good method to determine if the set is empty. Use isEmpty

     * instead.

     *

     * This is a utility method that call iterator and retrieve the first

     * feature of the iterator.

     *

     * @return the first fearure of the set or null.

     */

    public Feature first();

    /**

     * Updates a {@link Feature} with the given {@link EditableFeature}.<br>

     *

     * Any {@link DisposableIterator} from this store that was still in use can

     * will not reflect this change.

     *

     * @param feature an instance of {@link EditableFeature} with which to

     * update the associated {@link Feature}.

     *

     * @throws DataException

     */

    public void update(EditableFeature feature) throws DataException;

    public void commitChanges() throws DataException;

    /**

     * Deletes a {@link Feature} from this FeatureSet.<br>

     *

     * Any {@link DisposableIterator} from this store that was still in use will

     * be

     * <i>unsafe</i>. Use {@link DisposableIterator#remove()} instead.

     *

     * @param feature the {@link Feature} to delete.

     *

     * @throws DataException

     */

    public void delete(Feature feature) throws DataException;

    /**

     * Inserts a new feature in this set. It needs to be an instance of

     * {@link EditableFeature} as it has not been stored yet.<br>

     *

     * Any {@link DisposableIterator} from this store that was still in use can

     * will not reflect this change.

     *

     * @param feature the {@link EditableFeature} to insert.

     *

     * @throws DataException

     */

    public void insert(EditableFeature feature) throws DataException;

    /**

     * Returns a {@link DynObjectSet} of the contents of this set. Defaults to

     * fast iteration.

     *

     * @return a {@link DynObjectSet}

     */

    public DynObjectSet getDynObjectSet();

    /**

     * Returns a {@link DynObjectSet} of the contents of this set.

     *

     * @param fast if the set will be able to be iterated in a fast way, by

     * reusing the {@link DynObject} instance for each {@link Feature} instance.

     * @return a {@link DynObjectSet}

     */

    public DynObjectSet getDynObjectSet(boolean fast);

    /**

     * Provides each value of this Store to the provided {@link Visitor},

     * beginning from the provided index position. The values received through

     * the {@link Visitor#visit(Object)} method may be transient, reused or

     * externally modifiable, so they can't be used to be stored in any external

     * form out of the visit method.

     *

     * If you need to store any of the values out of the

     * {@link Visitor#visit(Object)} method execution, create a copy or clone

     * the received value in order to be stored.

     *

     * @param visitor the visitor to apply to each value.

     * @param firstValueIndex index of first element to be visited by the

     * {@link Visitor}

     * @exception BaseException if there is an error while performing the visit

     */

    @Override

    void accept(Visitor visitor, long firstValueIndex) throws BaseException;

    void accept(Visitor visitor, long firstValueIndex, long elements) throws BaseException;

    public FeatureStore getFeatureStore();

    @Deprecated 

    public JsonArray toJSON();

    public JsonArray toJson();

    public JsonArrayBuilder toJsonBuilder();

    public Expression makeFilter(int maxfeatures);

}