EDIT

/**

* Copyright (C) 2007 EDIT

* European Distributed Institute of Taxonomy 

* http://www.e-taxonomy.eu

* 

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.cdm.print;

import java.util.UUID;

import org.apache.logging.log4j.LogManager;import org.apache.logging.log4j.Logger;

import org.jdom.Element;

import org.jdom.JDOMException;

import org.jdom.Text;

import org.jdom.xpath.XPath;

/**

 * @author n.hoffmann

 * @since Apr 9, 2010

 * @version 1.0

 */

public class XMLHelper {

	private static final Logger logger = LogManager.getLogger(XMLHelper.class);

	public enum EntityType{

		CLASSIFICATION("Classification"), 

		TAXON_NODE("TaxonNode"),

		EMPTY("");

		private String cdmClassName;

		EntityType(String cdmClassName){

			this.cdmClassName = cdmClassName;

		}

		public static EntityType getEntityType(String cdmClassName){

			for(EntityType entityType : values()){

				if(entityType.getCdmClassName().equals(cdmClassName)){

					return entityType;

				}

			}

			return EMPTY;

		}

		private String getCdmClassName() {

			return cdmClassName;

		}

	}

	public static final String ELEMENT_CLASS = "class";

	public static final String ELEMENT_UUID = "uuid";

	public static final String ELEMENT_TITLE_CACHE = "titleCache";

	public static EntityType getEntityType(Element element) {

		return EntityType.getEntityType(getClazz(element));

	}

	public static UUID getUuid(Element element) {

		String content = getContent(element, ELEMENT_UUID);

		UUID uuid = null;

		try{

			uuid = UUID.fromString(content);

		}catch(IllegalArgumentException e){

			throw new RuntimeException(e);

		}

		return uuid;

	}

	public static String getClazz(Element element) {

		return getContent(element, ELEMENT_CLASS);

	}

	public static String getTitleCache(Element element) {

		return getContent(element, ELEMENT_TITLE_CACHE);

	}

	public static String getTitleCacheOfTaxonNode(Element treeNodeElement) {

		if(EntityType.TAXON_NODE.equals(getEntityType(treeNodeElement))){

			Element element;

			try {

				element = (Element) XPath.selectSingleNode(treeNodeElement, "taxon/name");

				if(element != null){

					return getContent(element, ELEMENT_TITLE_CACHE);

				}else{

					logger.error("Could not find title cache for taxonNode/taxon/name path");

				}

			} catch (JDOMException e) {

				logger.error("Could not find title cache for taxonNode/taxon/name path", e);

			} catch (Exception e) {

				logger.error("Exception while trying to retrieve title cache for taxon", e);

			}			

		}

		return getTitleCache(treeNodeElement);

	}

	public static Element getTaxonFromTaxonNode(Element taxonNodeElement) {

		if(EntityType.TAXON_NODE.equals(getEntityType(taxonNodeElement))){

			Element element;

			try {

				element = (Element) XPath.selectSingleNode(taxonNodeElement, "taxon");

				return element;

			} catch (JDOMException e) {

				logger.error("Could not find title cache for taxonNode/taxon/name path", e);

			} catch (Exception e) {

				logger.error("Exception while trying to retrieve title cache for taxon", e);

			}			

		}

		return null;

	}

	/**

	 * Adds an element as a child to another element

	 * 

	 * @param elementToAdd

	 * @param parentElement

	 */

	public static void addContent(Element elementToAdd, Element parentElement){

		elementToAdd.detach();

		parentElement.addContent(elementToAdd);

	}

	/**

	 * Adds an element to the child element of another element using the given name to select the child element

	 * 

	 * @param elementToAdd

	 * @param childElementName

	 * @param parentElement

	 */

	public static void addContent(Element elementToAdd, String childElementName, Element parentElement){

		if(elementToAdd == null){

			logger.warn("Retrieved a null element. Not adding it.");

			return;

		}

		if(parentElement == null){

			throw new IllegalArgumentException("Target element may not be null");

		}

		// create element if it did not exist before

		if(parentElement.getChild(childElementName) == null){

			parentElement.addContent(new Element(childElementName));

		}

		Element elementToAddClone = (Element) elementToAdd.clone();

		elementToAddClone.detach();

		Element childElement = parentElement.getChild(childElementName);

		childElement.addContent(elementToAddClone);

	}

	/*********** PRIVATE METHODS ********************/

	/**

	 * Returns the content of a child of <code>this</code> element 

	 * with the given element name.

	 * 

	 * @param elementName the name of a child element

	 * @return a String represting the content of the XML element with the given name

	 */

	private static String getContent(Element element, String elementName){

		if(element == null){

			logger.error("Element is null");

			return "";

		}

		Element contentElement = element.getChild(elementName);

		if(contentElement != null){

			Text content = (Text) contentElement.getContent().iterator().next();

			return content.getText();

		}

		return null;

	}

}