SESConstraintFilter.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.
 */
package org.n52.ses.api.ws;

import java.io.IOException;

import org.apache.muse.util.xml.XmlUtils;
import org.apache.muse.ws.notification.Filter;
import org.apache.muse.ws.notification.NotificationMessage;
import org.apache.muse.ws.notification.WsnConstants;
import org.n52.ses.api.common.SesConstants;
import org.n52.ses.api.eml.IEML;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.xml.sax.SAXException;



/**
 * This is the wrapper class for Level-2/3-Filtering.
 * 
 * @author Matthes Rieke <m.rieke@uni-muenster.de>
 *
 */
public class SESConstraintFilter implements Filter, IConstraintFilter {

	private static final Logger logger = LoggerFactory
			.getLogger(SESConstraintFilter.class);
	
	private IEML emlXml;


	/**
	 * Constructor
	 *
	 * @param eml EML document
	 */
	public SESConstraintFilter(IEML eml) {
		this.emlXml = eml;
	}


	/**
	 * 
	 * @return the EML type of this constraint filter
	 */
	public IEML getEml() {
		if (this.emlXml != null) {
			return this.emlXml;
		}
		return null;
	}

	/* (non-Javadoc)
	 * @see org.apache.muse.ws.notification.Filter#accepts(org.apache.muse.ws.notification.NotificationMessage)
	 */
	@Override
	public boolean accepts(NotificationMessage message) {
		return false;
	}

	@Override
	public Element toXML() {
		return toXML(XmlUtils.createDocument());
	}

	@Override
	public Element toXML(Document doc) {
		Element filter = XmlUtils.createElement(doc, WsnConstants.FILTER_QNAME);

		//hack to get the <Filter> Element of OGCFilter
		String xmlText = "<MessageContent>\n";
		if (this.emlXml != null)
			xmlText += this.emlXml.toString();
		else
			return null;
		xmlText += "\n</MessageContent>";

		Element message = null;
		try {
			Element node = XmlUtils.createDocument(xmlText).getDocumentElement();
			message = XmlUtils.createElement(doc, WsnConstants.MESSAGE_CONTENT_QNAME,
					node);
			message.setAttribute(WsnConstants.DIALECT, SesConstants.SES_FILTER_LEVEL_3_DIALECT);
		} catch (IOException e) {
			logger.warn(e.getMessage(), e);
		} catch (SAXException e) {
			logger.warn(e.getMessage(), e);
		}

		filter.appendChild(message);

		return filter;
	}


	


	@Override
	public String toString() {
		return XmlUtils.toString(toXML(), false).trim();
	}


}