tim@11: package de.intevation.gnv.util;
tim@11: 
tim@11: import java.io.ByteArrayOutputStream;
tim@11: import java.io.File;
tim@11: import java.io.UnsupportedEncodingException;
ingo@394: import java.util.HashMap;
ingo@394: import java.util.Map;
tim@11: 
tim@11: import javax.xml.transform.Source;
tim@11: import javax.xml.transform.Transformer;
tim@11: import javax.xml.transform.TransformerConfigurationException;
tim@11: import javax.xml.transform.TransformerException;
tim@11: import javax.xml.transform.TransformerFactory;
tim@11: import javax.xml.transform.TransformerFactoryConfigurationError;
tim@11: import javax.xml.transform.dom.DOMSource;
tim@11: import javax.xml.transform.stream.StreamResult;
tim@11: import javax.xml.transform.stream.StreamSource;
tim@11: 
sascha@396: import org.apache.log4j.Logger;
tim@11: import org.w3c.dom.Node;
tim@11: 
tim@11: /**
ingo@690:  * This xsl transformer is used to transform incoming xml documents with the
ingo@690:  * help of templates into a html representation.
sascha@699:  *
sascha@684:  * @author <a href="mailto:tim.englich@intevation.de">Tim Englich</a>
tim@11:  */
tim@11: public class XSLTransformer {
tim@962: 
tim@11:     /**
tim@11:      * the logger, used to log exceptions and additonaly information
tim@11:      */
tim@11:     private static Logger log = Logger.getLogger(XSLTransformer.class);
tim@36: 
tim@962:     /**
tim@962:      * The parameter that is required in the XSL sheet.
tim@962:      */
ingo@394:     private Map<String, String> params;
ingo@394: 
tim@11:     /**
tim@11:      * Constructor
tim@11:      */
tim@11:     public XSLTransformer() {
tim@11:         super();
tim@11:     }
tim@36: 
ingo@690:     /**
ingo@690:      * Turns <i>toTransform</i> into another format using the template <i>
ingo@690:      * templateFileName</i> with the <i>encoding</i>. The parameters added in
ingo@690:      * {@link #addParameter(java.lang.String, java.lang.String)} are available
ingo@690:      * in the transformer.
sascha@699:      *
ingo@690:      * @param toTransform The node to be transformed.
ingo@690:      * @param encoding The encoding to be used.
ingo@690:      * @param templateFileName The template used for transformation.
ingo@690:      * @return the transformed document as string.
ingo@690:      */
tim@36:     public String transform(Node toTransform, String encoding,
tim@38:                             String templateFileName) {
tim@11:         String resultValue = null;
tim@36:         try {
tim@36:             Source templateSource = new StreamSource(new File(templateFileName));
tim@36:             TransformerFactory xformFactory = TransformerFactory.newInstance();
tim@36:             Transformer transformer = xformFactory
tim@36:                     .newTransformer(templateSource);
ingo@394: 
ingo@394:             if (params != null) {
ingo@394:                 for(Map.Entry<String, String> entry: params.entrySet()) {
ingo@394:                     transformer.setParameter(entry.getKey(), entry.getValue());
ingo@394:                 }
ingo@394:             }
ingo@394: 
tim@36:             ByteArrayOutputStream baos = new ByteArrayOutputStream();
tim@36:             StreamResult scrResult = new StreamResult(baos);
tim@36:             // log.debug(xmlUtils.writeNode2String(toTransform));
tim@36:             DOMSource source = new DOMSource(toTransform);
tim@36:             transformer.transform(source, scrResult);
tim@36:             resultValue = new String(baos.toByteArray(), encoding);
tim@36:         } catch (TransformerConfigurationException e) {
tim@36:             log.error(e, e);
tim@36:         } catch (UnsupportedEncodingException e) {
tim@36:             log.error(e, e);
tim@36:         } catch (TransformerFactoryConfigurationError e) {
tim@36:             log.error(e, e);
tim@36:         } catch (TransformerException e) {
tim@36:             log.error(e, e);
tim@36:         }
tim@36: 
tim@11:         return resultValue;
tim@11:     }
tim@11: 
ingo@394: 
ingo@690:     /**
ingo@690:      * Add a parameter that is required in the XSL sheet.
ingo@690:      *
ingo@690:      * @param name The name of the parameter.
ingo@690:      * @param value The value of the parameter.
ingo@690:      */
ingo@394:     public void addParameter(String name, String value) {
ingo@394:         if (params == null) {
ingo@1008:             params = new HashMap<String, String>(3);
ingo@394:         }
ingo@394: 
ingo@394:         params.put(name, value);
ingo@394:     }
tim@11: }
sascha@700: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :