Metacat

/**

 *  '$RCSfile$'

 *  Copyright: 2005 University of New Mexico and the 

 *             Regents of the University of California and the

 *             National Center for Ecological Analysis and Synthesis

 *   '$Author: daigle $'

 *     '$Date: 2008-03-18 16:31:08 -0700 (Tue, 18 Mar 2008) $'

 * '$Revision: 3768 $'

 *

 * 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 2 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, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

 */

package edu.ucsb.nceas.metacat.advancedsearch;

import java.io.*;

import javax.xml.transform.Result;

import javax.xml.transform.Source;

import javax.xml.transform.Transformer;

import javax.xml.transform.TransformerConfigurationException;

import javax.xml.transform.TransformerException;

import javax.xml.transform.TransformerFactory;

import org.apache.log4j.Logger;

import edu.ucsb.nceas.metacat.MetaCatUtil;

/**

 * @author dcosta

 * 

 * Stylizer class applies the resultset.xsl stylesheet to the pathquery

 * results returned by Metacat.

 */

public class Stylizer {

  private Logger logMetacat = Logger.getLogger(Stylizer.class);

  /**

   * Applies the resultset.xsl stylesheet to the pathquery result string

   * returned by Metacat.

   * 

   * @param resultset       the pathquery result string from Metacat

   * @param sessionId       the user's session id

   * @param metacatURL      the URL to the Metacat server

   * @param qformat         The qformat (skin) to use when displaying results.

   * @param xslPath         File path to the resultset.xsl stylesheet.

   * 

   * @return htmlString     the result of the transformation from XML to HTML

   */

  public String resultsetToHTML(final String resultset, 

                                final String sessionId,

                                final String metacatURL,

                                final String qformat,

                                final String xslPath) {

    String htmlString = "";

    Result result;

    StringWriter stringWriter = new StringWriter();

    Transformer transformer;

    TransformerFactory transformerFactory;

    Source xmlSource;

    File xsltFile = new File(xslPath);            

    Source xsltSource;

    StringReader stringReader = new StringReader(resultset);

    xmlSource = new javax.xml.transform.stream.StreamSource(stringReader);

    xsltSource = new javax.xml.transform.stream.StreamSource(xsltFile);

    result = new javax.xml.transform.stream.StreamResult(stringWriter);

    // create an instance of TransformerFactory

    transformerFactory = TransformerFactory.newInstance();

    try {

      transformer = transformerFactory.newTransformer(xsltSource);

      MetaCatUtil metaCatUtil = new MetaCatUtil();

      String httpServer = MetaCatUtil.getOption("httpserver");

      String context = MetaCatUtil.getOption("context");

      // Log error if httpserver or context are not set in metacat

      // configuration, but allow transform to proceed.  User will

      // see data, albeit without pretty formatting.

      if (httpServer == null || context == null) {

    	logMetacat.error("httpserver and context values must be set in " +

    			"metacat configuration for advanced search formatting to " +

    			"work properly");

      } else {

        transformer.setParameter("contextURL", httpServer+"/"+context+"/");

      }

      if (sessionId != null) {

        transformer.setParameter("sessid", sessionId);

      }

      transformer.setParameter("metacatURL", metacatURL);

      if ((qformat != null) && (!qformat.equals(""))) {

        transformer.setParameter("qformat", qformat);

      }

      transformer.transform(xmlSource, result);

      htmlString = stringWriter.toString();

    }

    catch (TransformerConfigurationException tce) {

      // Error generated by the parser

      Throwable x = tce;  // Use the contained exception, if any

      if (tce.getException() != null) {

        x = tce.getException();    

      }

      x.printStackTrace();   

    }

    catch (TransformerException te) {

      // Error generated by the parser

      Throwable x = te;  // Use the contained exception, if any

      if (te.getException() != null) {

        x = te.getException();    

      }

      x.printStackTrace(); 

    }

    return htmlString;

  }

}