EqualToFilter.java

/**
 * Copyright (C) 2008 - 2014 52°North Initiative for Geospatial Open Source
 * Software GmbH
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 *
 * If the program is linked with libraries which are licensed under one of
 * the following licenses, the combination of the program with the linked
 * library is not considered a "derivative work" of the program:
 *
 *     - Apache License, version 2.0
 *     - Apache Software License, version 1.0
 *     - GNU Lesser General Public License, version 3
 *     - Mozilla Public License, versions 1.0, 1.1 and 2.0
 *     - Common Development and Distribution License (CDDL), version 1.0
 *
 * Therefore the distribution of the program linked with libraries licensed
 * under the aforementioned licenses, is permitted by the copyright holders
 * if the distribution is compliant with both the GNU General Public
 * icense version 2 and the aforementioned licenses.
 *
 * 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.
 */
/**
 * Part of the diploma thesis of Thomas Everding.
 * @author Thomas Everding
 */

package org.n52.ses.eml.v002.filter.comparison;

import java.util.HashSet;


import net.opengis.fes.x20.BinaryComparisonOpType;


/**
 * filters via ==
 * 
 * @author Thomas Everding
 *
 */
public class EqualToFilter extends ABinaryComparisonFilter{
	
	/**
	 * 
	 * Constructor
	 *
	 * @param binaryOp filter definition
	 * @param propertyNames names of the properties used in this filter / pattern
	 */
	public EqualToFilter(BinaryComparisonOpType binaryOp, HashSet<Object > propertyNames) {
		this.initialize(binaryOp, propertyNames);
	}

	
	@Override
	public String createExpressionString(boolean complexPatternGuard) {
		String result = "";
		
		if (this.first.getUsedProperty() != null || this.second.getUsedProperty() != null) {
			
			result += createUsedPropertyString();

		}
		
		String firstString = this.first.createExpressionString(complexPatternGuard);
		String secondString = this.second.createExpressionString(complexPatternGuard);
		
		/*
		 * check if the format is parsable with esper. otherwise
		 * change it (add quotes etc.)
		 */
		String[] a = checkDataTypes(complexPatternGuard, firstString, secondString);
		firstString = a[0];
		secondString = a[1];
		
		result += "("
						+ firstString
						+ " = "
						+ secondString
						+")";
		return result;
	}
}