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.gui.beans.comboboxconfigurablelookup.agents;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import java.util.Vector;

import org.gvsig.gui.beans.comboboxconfigurablelookup.ILookUp;

import org.gvsig.gui.beans.comboboxconfigurablelookup.StringComparator;

/**

 * <p>Agent that looks up items of an locale-rules alphabetically sort ordered <code>Vector</code> that

 *  start with a text. Those items will be returned as a {@link List List}.</p>

 * 

 * <p>Supports two versions: with or without considering case sensitive.</p>

 * 

 * @version 07/02/2008

 * @author Pablo Piqueras Bartolom? (pablo.piqueras@iver.es) 

 */

public class StartsWithLookUpAgent implements ILookUp {

        /**

         * <p>Creates a new instance of the class <code>StartsWithLookUpAgent</code>.</p>

         */

        public StartsWithLookUpAgent() {

        }

        /*

         * (non-Javadoc)

         * @see org.gvsig.gui.beans.comboboxconfigurablelookup.ILookUp#doLookUpConsideringCaseSensitive(java.lang.String, java.util.Vector, org.gvsig.gui.beans.comboboxconfigurablelookup.StringComparator)

         */

        public synchronized List<Object> doLookUpConsideringCaseSensitive(String text, Vector<Object> sortOrderedItems, StringComparator comp) {

                if (text == null)

                        return null;

                List<Object> results_list = doLookUpIgnoringCaseSensitive(text, sortOrderedItems, comp);

                if (results_list == null)

                        return null;

                List<Object> results = new ArrayList<Object>();

                for (int i = 0; i < (results_list.size()); i++) {

                        if (results_list.get(i).toString().startsWith(text)) {

                                results.add(results_list.get(i));

                        }

                }

                return results;

        }

        /*

         * (non-Javadoc)

         * @see org.gvsig.gui.beans.comboboxconfigurablelookup.ILookUp#doLookUpIgnoringCaseSensitive(java.lang.String, java.util.Vector, org.gvsig.gui.beans.comboboxconfigurablelookup.StringComparator)

         */

        public synchronized List<Object> doLookUpIgnoringCaseSensitive(String text, Vector<Object> sortOrderedItems, StringComparator comp) {

                if (text == null)

                        return null;

                int currentIteration = 0;

                int size = sortOrderedItems.size();

                int maxNumberOfIterations = (int) (Math.log(size) / Math.log(2));

                int lowIndex = 0;

                int highIndex = sortOrderedItems.size() - 1;

                int mIndx;

                while ((lowIndex <= highIndex) && (currentIteration <= maxNumberOfIterations)) {

                        mIndx = ( lowIndex + highIndex ) / 2;

                        if ( sortOrderedItems.get( mIndx ).toString().toLowerCase().startsWith( text.toLowerCase() ) ) {

                                lowIndex = highIndex = mIndx;

                                highIndex ++;

                                // Expand the rank to up

                                while ( ( highIndex < size ) && ( sortOrderedItems.get( highIndex ).toString().toLowerCase().startsWith( text.toLowerCase() ) ) ) {

                                        highIndex ++;

                                }

                                // Expand the rank to down

                                while ( ( (lowIndex - 1) > -1 ) && ( sortOrderedItems.get( (lowIndex - 1) ).toString().toLowerCase().startsWith( text.toLowerCase() ) ) ) {

                                        lowIndex --;

                                }

                                // Returns all items in the rank                        

                                return Arrays.asList((sortOrderedItems.subList(lowIndex, highIndex)).toArray()); // Breaks the loop

                        }

                        else {

                                if ( comp.compare(sortOrderedItems.get( mIndx ).toString().toLowerCase(), text.toLowerCase() ) > 0 ) {

                                        highIndex = mIndx - 1;

                                }

                                else {

                                        lowIndex = mIndx + 1;

                                }

                        }

                        currentIteration ++;

                }

                return null;

        }

}