org.apache.oodt.cas.product.jaxrs.configurations.RssConfiguration.java Source code

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Here is the source code for org.apache.oodt.cas.product.jaxrs.configurations.RssConfiguration.java

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/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

package org.apache.oodt.cas.product.jaxrs.configurations;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.List;
import java.util.Vector;

import org.apache.commons.lang.StringEscapeUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.lang.WordUtils;
import org.apache.oodt.cas.metadata.Metadata;
import org.apache.oodt.cas.metadata.util.PathUtils;
import org.apache.oodt.commons.xml.XMLUtils;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

/**
 * Class representing custom configurations for RSS XML outputs.
 * @author rlaidlaw
 * @version $Revision$
 */
public class RssConfiguration {
    private static final String CHANNEL_LINK = "channelLink";
    private static final String NAMESPACE = "namespace";
    private static final String NAMESPACE_KEY = "prefix";
    private static final String NAMESPACE_VALUE = "uri";
    private static final String TAG = "tag";
    private static final String TAG_NAME = "name";
    private static final String TAG_SOURCE = "source";
    private static final String ATTRIBUTE = "attribute";
    private static final String ATTRIBUTE_NAME = "name";
    private static final String ATTRIBUTE_VALUE = "value";

    private List<RssNamespace> namespaceList = new Vector<RssNamespace>();
    private List<RssTag> tagList = new Vector<RssTag>();
    private String channelLink = null;

    /**
     * Initializes the parameters in the configuration object using values from
     * the supplied file.
     * @param file the configuration file
     * @throws IOException if the file does not exist and cannot be read
     */
    public void initialize(File file) throws IOException {
        FileInputStream fis = new FileInputStream(file);
        Document document = XMLUtils.getDocumentRoot(fis);
        Element root = document.getDocumentElement();

        channelLink = root.getAttribute(CHANNEL_LINK);
        namespaceList = readNamespaces(root);
        tagList = readTags(root);

        fis.close();
    }

    private List<RssNamespace> readNamespaces(Element root) {
        List<RssNamespace> namespaces = new Vector<RssNamespace>();
        NodeList nodeList = root.getElementsByTagName(NAMESPACE);
        if (nodeList != null && nodeList.getLength() > 0) {
            for (int i = 0; i < nodeList.getLength(); i++) {
                Element element = (Element) nodeList.item(i);
                namespaces.add(new RssNamespace(element.getAttribute(NAMESPACE_KEY),
                        element.getAttribute(NAMESPACE_VALUE)));
            }
        }
        return namespaces;
    }

    private List<RssTag> readTags(Element root) {
        List<RssTag> tags = new Vector<RssTag>();
        NodeList list = root.getElementsByTagName(TAG);
        if (list != null && list.getLength() > 0) {
            for (int i = 0; i < list.getLength(); i++) {
                Element element = (Element) list.item(i);
                tags.add(new RssTag(element.getAttribute(TAG_NAME), element.getAttribute(TAG_SOURCE),
                        readAttributes(element)));
            }
        }
        return tags;
    }

    private List<RssTagAttribute> readAttributes(Element element) {
        List<RssTagAttribute> attributes = new Vector<RssTagAttribute>();
        NodeList nodeList = element.getElementsByTagName(ATTRIBUTE);
        if (nodeList != null && nodeList.getLength() > 0) {
            for (int i = 0; i < nodeList.getLength(); i++) {
                Element attribute = (Element) nodeList.item(i);
                attributes.add(new RssTagAttribute(attribute.getAttribute(ATTRIBUTE_NAME),
                        attribute.getAttribute(ATTRIBUTE_VALUE)));
            }
        }
        return attributes;
    }

    /**
     * Gets the list of namespaces.
     * @return the list of namespaces
     */
    public List<RssNamespace> getNamespaceList() {
        return namespaceList;
    }

    /**
     * Gets the channel link URL string.
     * @return the channel link URL string
     */
    public String getChannelLink() {
        return channelLink;
    }

    /**
     * Appends elements (tags) defined in a configuration file to a specific
     * parent element.
     * @param metadata the metadata for the product
     * @param document the document to which these elements belong
     * @param parent the parent element to attach these elements to
     */
    public void appendTags(Metadata metadata, Document document, Element parent) {
        for (RssTag tag : tagList) {
            String tagName = tag.getName();
            if (tagName.contains(" ")) {
                tagName = StringUtils.join(WordUtils.capitalizeFully(tagName).split(" "));
            }

            // Create a new element for the tag.
            Element element = XMLUtils.addNode(document, parent, tagName);

            // Add a value for the tag from the tag source.
            if (tag.getSource() != null) {
                element.appendChild(document.createTextNode(
                        StringEscapeUtils.escapeXml(PathUtils.replaceEnvVariables(tag.getSource(), metadata))));
            }

            // Add attributes to the tag as defined in the configuration.
            for (RssTagAttribute attribute : tag.getAttributes()) {
                element.setAttribute(attribute.getName(),
                        PathUtils.replaceEnvVariables(attribute.getValue(), metadata));
            }
        }
    }
}