org.glite.lb.NotifParser.java Source code

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Here is the source code for org.glite.lb.NotifParser.java

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/*
Copyright (c) Members of the EGEE Collaboration. 2004-2010.
See http://www.eu-egee.org/partners for details on the copyright holders.
    
Licensed 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.
*/

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package org.glite.lb;

import java.io.IOException;
import java.io.StringReader;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.apache.commons.lang.StringEscapeUtils;
import org.glite.wsdl.types.lb.JobStatus;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

/**
 * this class parses the received message into a readable format
 *
 * @author Kopac
 */
public class NotifParser {

    Document doc = null;
    String header = null;

    /**
     * constructor takes a notification in String format and parses it into a String
     * containing the header and an XML doc
     *
     * @param notif the string with notification in it
     * @throws javax.xml.parsers.ParserConfigurationException
     * @throws org.xml.sax.SAXException
     * @throws java.io.IOException
     */
    public NotifParser(String notif) throws ParserConfigurationException, SAXException, IOException {
        String[] splitString = notif.split("DG.NOTIFICATION.JOBSTAT=\"", 2);
        header = splitString[0];
        doc = createXML(splitString[1]);
    }

    /**
     * this method reads through an XML document using XPath expressions and
     * fills an instance of JobStatus, which it then returns
     * this is done using automatically generated code
     *
     * @param notification an array of bytes containing the raw notification
     * @return a Jobstatus instance
     */
    public JobStatus getJobInfo() throws ParserConfigurationException, SAXException, IOException {
        JobStatus status = new JobStatus();
        //TODO: insert automated code creation
        status.setJobId(evaluateXPath("//jobId").item(0).getTextContent());
        status.setOwner(evaluateXPath("//owner").item(0).getTextContent());
        return status;
    }

    /**
    * this method returns id of the notification
    *
    * @return notif id
    */
    public String getNotifId() {
        String halfHeader = header.split("DG.NOTIFICATION.NOTIFID=\"")[1];
        return halfHeader.substring(0, halfHeader.indexOf("\""));
    }

    /**
     * a method for handling xpath queries
     *
     * @param xpathString xpath expression
     * @return the result nodelist
     */
    private NodeList evaluateXPath(String xpathString) {
        try {
            XPathFactory xfactory = XPathFactory.newInstance();
            XPath xpath = xfactory.newXPath();
            XPathExpression expr = xpath.compile(xpathString);
            return (NodeList) expr.evaluate(doc, XPathConstants.NODESET);
        } catch (XPathExpressionException ex) {
            ex.printStackTrace();
            return null;
        }
    }

    /**
     * this method creates an XML document out of a provided String
     * note that the string has to be a valid escaped XML document representation,
     * otherwise the process will fail
     *
     * @param body a String containing an XML document
     * @return an XML document in the Document format
     * @throws javax.xml.parsers.ParserConfigurationException
     * @throws org.xml.sax.SAXException
     * @throws java.io.IOException
     */
    private Document createXML(String body) throws ParserConfigurationException, SAXException, IOException {
        String removed = body.substring(0, body.length() - 1);
        String parsed = StringEscapeUtils.unescapeXml(removed);
        //this code removes hexadecimal references from the string (couldn't find
        //a suitable parser for this)
        StringBuilder build = new StringBuilder(parsed);
        int j = build.indexOf("%");
        while (j > 0) {
            if (build.charAt(j - 1) == '>') {
                build.delete(j, j + 3);
                if (build.charAt(j) == '<') {
                    j = build.indexOf("%");
                }
            } else {
                j = build.indexOf("%", j + 1);
            }
        }
        parsed = build.toString();
        //ends here
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        return factory.newDocumentBuilder().parse(new InputSource(new StringReader(parsed)));
    }
}