XpathAttributesDynamicConfiguration.java

/*
 * gvNIX is an open source tool for rapid application development (RAD).
 * Copyright (C) 2010 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 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, see <http://www.gnu.org/licenses/>.
 */
package org.gvnix.dynamic.configuration.roo.addon.config;

import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;

import org.apache.felix.scr.annotations.Component;
import org.gvnix.dynamic.configuration.roo.addon.entity.DynProperty;
import org.gvnix.dynamic.configuration.roo.addon.entity.DynPropertyList;
import org.springframework.roo.process.manager.MutableFile;
import org.springframework.roo.support.logging.HandlerUtils;
import org.springframework.roo.support.util.XmlUtils;
import org.w3c.dom.Attr;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

/**
 * Abstract dynamic configuration component of XML files for managing elements
 * attributes with Xpath expressions.
 * <p>
 * Extends this class to manage new XML file values with Xpath attributes
 * expressions.
 * </p>
 * 
 * @author <a href="http://www.disid.com">DISID Corporation S.L.</a> made for <a
 *         href="http://www.dgti.gva.es">General Directorate for Information
 *         Technologies (DGTI)</a>
 */
@Component(componentAbstract = true)
public abstract class XpathAttributesDynamicConfiguration extends
        XpathDynamicConfiguration {

    private static final Logger logger = HandlerUtils
            .getLogger(XpathAttributesDynamicConfiguration.class);

    /**
     * {@inheritDoc}
     */
    @Override
    public DynPropertyList read() {

        DynPropertyList dynProps = new DynPropertyList();

        // Get the XML file path
        MutableFile file = getFile();

        // If managed file not exists, nothing to do
        if (file != null) {

            // Obtain the XML file on DOM document format
            Document doc = getXmlDocument(file);

            // Obtain all xpath elements that contains the key attribute
            List<Element> elems = XmlUtils.findElements(getXpath()
                    + XPATH_ARRAY_PREFIX + XPATH_ATTRIBUTE_PREFIX + getKey()
                    + XPATH_ARRAY_SUFIX, doc.getDocumentElement());
            for (Element elem : elems) {

                // If key attribute exists, create current dynamic property
                String key = elem.getAttribute(getKey());
                String value = elem.getAttribute(getValue());
                if (key.isEmpty()) {

                    logger.log(Level.WARNING, "Element attribute " + elem
                            + " to get not exists on file");
                    continue;
                }
                dynProps.add(new DynProperty(setKeyValue(key), value));
            }
        }

        return dynProps;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void write(DynPropertyList dynProps) {

        // Get the XML file path
        MutableFile file = getFile();
        if (file != null) {

            // Obtain document representation of the XML file
            Document doc = getXmlDocument(file);

            // Update the root element property values with dynamic properties
            for (DynProperty dynProp : dynProps) {

                // Obtain the element related to this dynamic property
                String xpath = getXpath() + XPATH_ARRAY_PREFIX
                        + XPATH_ATTRIBUTE_PREFIX + getKey()
                        + XPATH_EQUALS_SYMBOL + XPATH_STRING_DELIMITER
                        + getKeyValue(dynProp.getKey())
                        + XPATH_STRING_DELIMITER + XPATH_ARRAY_SUFIX;
                Element elem = XmlUtils.findFirstElement(xpath,
                        doc.getDocumentElement());
                if (elem == null) {

                    logger.log(Level.WARNING, "Element " + xpath
                            + " to set attribute value not exists on file");
                }
                else {

                    // If value attribute exists, set new value
                    Attr attr = elem.getAttributeNode(getValue());
                    if (attr == null) {

                        logger.log(Level.WARNING, "Element attribute " + xpath
                                + " to set value not exists on file");
                    }
                    else {

                        attr.setValue(dynProp.getValue());
                    }
                }
            }

            // Update the XML file
            XmlUtils.writeXml(file.getOutputStream(), doc);

        }
        else if (!dynProps.isEmpty()) {

            logger.log(Level.WARNING, "File " + getFilePath()
                    + " not exists and there are dynamic properties to set it");
        }
    }

}