Application: gvSIG desktop » Library: org.gvsig.tools

/* gvSIG. Geographic Information System of the Valencian Government

 *

 * Copyright (C) 2007-2008 Infrastructures and Transports Department

 * of the Valencian Government (CIT)

 *

 * 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 2

 * 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.

 *

 */

package org.gvsig.tools.dynobject.impl;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.gvsig.tools.dispose.DisposableIterator;

import org.gvsig.tools.dynobject.DynObject;

import org.gvsig.tools.dynobject.DynObjectSet;

import org.gvsig.tools.exception.BaseException;

import org.gvsig.tools.visitor.Visitor;

/**

 * Fa?ade for a list of {@link DynObjectSet}s as if they were an only contiguous

 * set of {@link DynObject}s.

 * 

 * @author gvSIG Team

 * @version $Id$

 */

public class MultiDynObjectSet implements DynObjectSet {

    private static final Logger LOG = LoggerFactory

        .getLogger(MultiDynObjectSet.class);

    private final DynObjectSet[] innerSets;

    /**

     * Creates a new {@link MultiDynObjectSet} with the list of

     * {@link DynObjectSet}s to fa?ade.

     */

    public MultiDynObjectSet(DynObjectSet[] innerSets) {

        this.innerSets = innerSets == null ? new DynObjectSet[0] : innerSets;

    }

    public void dispose() {

        for (int i = 0; i < innerSets.length; i++) {

            innerSets[i].dispose();

        }

    }

    public void accept(Visitor visitor, long firstValueIndex)

        throws BaseException {

        // Find the set where the global index points to

        int currentSet = 0;

        long currentIndex = 0;

        while (currentIndex + innerSets[currentSet].getSize() <= firstValueIndex) {

            currentIndex += innerSets[currentSet].getSize();

            currentSet++;

        }

        // Get the relative index into the current set

        long firstIndexFromCurrentSet = firstValueIndex - currentIndex;

        // Visit the current set beginning from the relative index

        innerSets[currentSet].accept(visitor, firstIndexFromCurrentSet);

        // Finally, visit the remaining sets fully.

        for (int i = currentSet; i < innerSets.length; i++) {

            innerSets[i].accept(visitor);

        }

    }

    public void accept(Visitor visitor) throws BaseException {

        accept(visitor, 0);

    }

    public long getSize() throws BaseException {

        long size = 0;

        for (int i = 0; i < innerSets.length; i++) {

            size += innerSets[i].getSize();

        }

        return size;

    }

    public DisposableIterator iterator(long index) throws BaseException {

        return new MultiDynObjectSetDisposableIterator(innerSets);

    }

    public DisposableIterator iterator() throws BaseException {

        return iterator(0);

    }

    public boolean isEmpty() throws BaseException {

        for (int i = 0; i < innerSets.length; i++) {

            if (!innerSets[i].isEmpty()) {

                return false;

            }

        }

        return true;

    }

    /**

     * @author gvSIG Team

     * @version $Id$

     * 

     */

    public static class MultiDynObjectSetDisposableIterator implements

        DisposableIterator {

        private DisposableIterator currentIterator = null;

        private int currentSet = 0;

        private final DynObjectSet[] innerSets;

        public MultiDynObjectSetDisposableIterator(DynObjectSet[] innerSets)

            throws BaseException {

            this.innerSets = innerSets;

            if (currentIterator == null && currentSet < innerSets.length) {

                currentIterator = innerSets[currentSet].iterator();

            }

        }

        public void dispose() {

            if (currentIterator != null) {

                currentIterator.dispose();

            }

        }

        private DisposableIterator getCurrentIterator() {

            while (!currentIterator.hasNext()

                && currentSet < innerSets.length - 1) {

                currentSet++;

                try {

                    currentIterator = innerSets[currentSet].iterator();

                } catch (BaseException e) {

                    LOG.error(

                        "Could no get the iterator of the internal DynObjectSet num. "

                            + currentSet + ": " + innerSets[currentSet], e);

                }

            }

            return currentIterator;

        }

        public boolean hasNext() {

            DisposableIterator currentIterator = getCurrentIterator();

            return currentIterator == null ? false : currentIterator.hasNext();

        }

        public Object next() {

            DisposableIterator currentIterator = getCurrentIterator();

            return currentIterator == null ? null : currentIterator.next();

        }

        public void remove() {

            throw new UnsupportedOperationException(

                "Unable to remove on composed DynObjectSet iterator");

        }

    }

}