Application: gvSIG desktop

/* gvSIG. Sistema de Informaci�n Geogr�fica de la Generalitat Valenciana

 *

 * Copyright (C) 2004 IVER T.I. and Generalitat Valenciana.

 *

 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307,USA.

 *

 * For more information, contact:

 *

 *  Generalitat Valenciana

 *   Conselleria d'Infraestructures i Transport

 *   Av. Blasco Ib��ez, 50

 *   46010 VALENCIA

 *   SPAIN

 *

 *      +34 963862235

 *   gvsig@gva.es

 *      www.gvsig.gva.es

 *

 *    or

 *

 *   IVER T.I. S.A

 *   Salamanca 50

 *   46005 Valencia

 *   Spain

 *

 *   +34 963163400

 *   dac@iver.es

 */

package org.gvsig.sldsupport.filterencoding;

import java.io.IOException;

import java.util.ArrayList;

import java.util.HashSet;

import java.util.Set;

import org.gvsig.sldsupport.exception.SLDReadException;

import org.xmlpull.v1.XmlPullParser;

import org.xmlpull.v1.XmlPullParserException;

/**

 * Implements the main functionalities to parse a logical operator

 * of a Filter Encoding expression<br>

 * 

 * A logical operator can be used to combine one or more conditional 

 * expressions. The logical operator AND evaluates to TRUE if all the 

 * combined expressions evaluate to TRUE. The operator OR evaluates to 

 * TRUE if is any of the combined expressions evaluate to TRUE. The NOT

 * operator reverses the logical value of an expression. 

 * 

 * @see http://www.opengeospatial.org/standards/filter

 * @author pepe vidal salvador - jose.vidal.salvador@iver.es

 */

public class FLogicOperator {

        String logicType;

        ArrayList<FComparisonOperator> compOperator = new ArrayList<FComparisonOperator>();

        ArrayList<FLogicOperator> logicOperators = new ArrayList<FLogicOperator>(); 

        ArrayList<FLogicOperatorNot> logicNotOperators = new ArrayList<FLogicOperatorNot>();

        Set <String> fieldNames = new HashSet <String>();

        int numOperators = 0;

        protected String opExpressionStr = "";

        public void parse(XmlPullParser parser, String tag)

                        throws XmlPullParserException, IOException, SLDReadException {

                int currentTag;

                boolean end = false;

                this.logicType = tag;

                parser.require(XmlPullParser.START_TAG, null, tag);

                currentTag = parser.next();

                while (!end)

                {

                        switch(currentTag)

                        {

                        case XmlPullParser.START_TAG:

                                if (parser.getName().compareTo(FilterUtils.remNameSpace(FilterTags.PROPERTYISEQUALTO))==0 ||

                                                parser.getName().compareTo(FilterUtils.remNameSpace(FilterTags.PROPERTYISNOTEQUALTO))==0 ||

                                                parser.getName().compareTo(FilterUtils.remNameSpace(FilterTags.PROPERTYISLESSTHAN))==0 ||

                                                parser.getName().compareTo(FilterUtils.remNameSpace(FilterTags.PROPERTYISGREATERTHAN))==0 ||

                                                parser.getName().compareTo(FilterUtils.remNameSpace(FilterTags.PROPERTYISLESSOREQUALTHAN))==0 ||

                                                parser.getName().compareTo(FilterUtils.remNameSpace(FilterTags.PROPERTYISGREATEROREQUALTHAN))==0)  {

                                        FComparisonOperator compOp = new FComparisonOperator();

                                        if(numOperators >= 1)

                                                opExpressionStr += FilterUtils.getSymbol4Expression("ogc:"+logicType)+" ";

                                        opExpressionStr += "( ";

                                        compOp.parse(parser , parser.getName());

                                        opExpressionStr += compOp.getOpExpressionStr();

                                        opExpressionStr += ") ";

                                        fieldNames.addAll(compOp.getFieldNames());

                                        compOperator.add(compOp);

                                        numOperators++;

                                }

                                else if (parser.getName().compareTo(FilterUtils.remNameSpace(FilterTags.AND)) ==0 ||

                                                parser.getName().compareTo(FilterUtils.remNameSpace(FilterTags.OR)) ==0)  {

                                        FLogicOperator propLog = new FLogicOperator();

                                        if(numOperators >= 1)

                                                opExpressionStr += FilterUtils.getSymbol4Expression("ogc:"+logicType)+" ";

                                        opExpressionStr += "( ";

                                        propLog.parse(parser , parser.getName());

                                        opExpressionStr += propLog.getOpExpressionStr();

                                        opExpressionStr += ") ";

                                        fieldNames.addAll(propLog.getFieldNames());

                                        logicOperators.add(propLog);

                                        numOperators++;

                                        if (propLog.getNumOperators() < 2) {

                                                throw new SLDReadException(new Exception(

                                                                "Found " + propLog.getNumOperators() + " operators, expected 2."));

                                        }

                                }

                                else if (parser.getName().compareTo(FilterUtils.remNameSpace(FilterTags.NOT)) ==0) {

                                        FLogicOperatorNot notlogicOperators = new FLogicOperatorNot();

                                        if(numOperators >= 1)

                                                opExpressionStr += FilterUtils.getSymbol4Expression("ogc:"+logicType)+" ";

                                        opExpressionStr += "( "+"! ";

                                        notlogicOperators.parse(parser,parser.getName());

                                        opExpressionStr += notlogicOperators.getOpExpressionStr();

                                        opExpressionStr += ") ";

                                        fieldNames.addAll(notlogicOperators.getFieldNames());

                                        logicNotOperators.add(notlogicOperators);

                                        numOperators++;

                                }

                                break;

                        case XmlPullParser.END_TAG:

                                if (parser.getName().compareTo(tag) == 0)

                                        end = true;

                                break;

                        case XmlPullParser.TEXT:

                                break;

                        }

                        if (!end)

                                currentTag = parser.next();

                }

                parser.require(XmlPullParser.END_TAG, null, tag);

        }

        public int getNumOperators() { return numOperators; }

        public void setNumOperators(int numOperators) {this.numOperators = numOperators; }

        public Set<String> getFieldNames() { return fieldNames; }

        public String getLogicType() {return logicType;}

        public ArrayList<FComparisonOperator> getCompOperator() {return compOperator;}

        public String getOpExpressionStr() {

                return opExpressionStr;

        }

}