source: trunk/EventBenchConsole/src/de/ugoe/cs/eventbench/jfc/JFCLogParser.java @ 357

package de.ugoe.cs.eventbench.jfc;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.security.InvalidParameterException;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;

import de.ugoe.cs.eventbench.jfc.data.JFCEvent;
import de.ugoe.cs.util.console.Console;

/**
 * <p>
 * This class provides functionality to parse XML log files generated by the
 * JFCMonitor of EventBench. The result of parsing a file is a collection of
 * event sequences.
 * </p>
 * 
 * @author Steffen Herbold
 * @version 1.0
 */
public class JFCLogParser extends DefaultHandler {

        /**
         * <p>
         * Collection of event sequences that is contained in the log file, which is
         * parsed.
         * </p>
         */
        private Collection<List<JFCEvent>> sequences;

        /**
         * <p>
         * Internal handle to the event that is currently being parsed.
         * </p>
         */
        private JFCEvent currentEvent;

        /**
         * <p>
         * Internal handle to the event sequence that is currently being parsed.
         * </p>
         */
        private List<JFCEvent> currentSequence = null;

        /**
         * <p>
         * Enumeration to differentiate if a parameter belongs to an event, a source
         * or the parent of a source.
         * </p>
         * 
         * @author Steffen Herbold
         * @version 1.0
         */
        private enum ParamSource {
                EVENT, SOURCE, PARENT
        };

        /**
         * <p>
         * Specifies whether the parameters that are currently being read belong the
         * the event, the source or the parent.
         * </p>
         */
        ParamSource paramSource = null;

        /**
         * <p>
         * Constructor. Creates a new JFCLogParser.
         * </p>
         */
        public JFCLogParser() {
                sequences = new LinkedList<List<JFCEvent>>();
                currentSequence = new LinkedList<JFCEvent>();
        }

        /**
         * <p>
         * Returns the collection of event sequences that is obtained from parsing
         * log files.
         * </p>
         * 
         * @return collection of event sequences
         */
        public Collection<List<JFCEvent>> getSequences() {
                return sequences;
        }

        /*
         * (non-Javadoc)
         * 
         * @see org.xml.sax.helpers.DefaultHandler#startElement(java.lang.String,
         * java.lang.String, java.lang.String, org.xml.sax.Attributes)
         */
        public void startElement(String uri, String localName, String qName,
                        Attributes atts) throws SAXException {
                if( qName.equals("sessions") ) {
                        currentSequence = new LinkedList<JFCEvent>();
                }
                if (qName.equals("newsession")) {
                        Console.traceln("start of session");
                        if (currentSequence != null && !currentSequence.isEmpty()) {
                                sequences.add(currentSequence);
                        }
                        currentSequence = new LinkedList<JFCEvent>();
                } else if (qName.equals("event")) {
                        currentEvent = new JFCEvent(atts.getValue("id"));
                        paramSource = ParamSource.EVENT;
                } else if (qName.equals("param")) {
                        if (paramSource == ParamSource.EVENT) {
                                currentEvent.addParameter(atts.getValue("name"),
                                                atts.getValue("value"));
                        } else if (paramSource == ParamSource.SOURCE) {
                                currentEvent.addSourceInformation(atts.getValue("name"),
                                                atts.getValue("value"));
                        } else if (paramSource == ParamSource.PARENT) {
                                currentEvent.addParentInformation(atts.getValue("name"),
                                                atts.getValue("value"));
                        }
                } else if (qName.equals("source")) {
                        paramSource = ParamSource.SOURCE;
                } else if (qName.equals("parent")) {
                        paramSource = ParamSource.PARENT;
                }
        }

        /*
         * (non-Javadoc)
         * 
         * @see org.xml.sax.helpers.DefaultHandler#endElement(java.lang.String,
         * java.lang.String, java.lang.String)
         */
        @Override
        public void endElement(String uri, String localName, String qName)
                        throws SAXException {
                if (qName.equals("event")) {
                        currentSequence.add(currentEvent);
                } else if (qName.equals("source")) {
                        paramSource = ParamSource.EVENT;
                } else if (qName.equals("parent")) {
                        paramSource = ParamSource.SOURCE;
                } else if (qName.equals("sessions")) {
                        if(currentSequence!=null && !currentSequence.isEmpty() ) {
                                sequences.add(currentSequence);
                        }
                        currentSequence = null;
                }
        }

        /**
         * <p>
         * Parses a log file written by the JFCMonitor and creates a collection of
         * event sequences.
         * </p>
         * 
         * @param filename
         *            name and path of the log file
         */
        public void parseFile(String filename) {
                if (filename == null) {
                        throw new InvalidParameterException("filename must not be null");
                }

                SAXParserFactory spf = SAXParserFactory.newInstance();
                spf.setValidating(true);

                SAXParser saxParser = null;
                InputSource inputSource = null;
                try {
                        saxParser = spf.newSAXParser();
                        inputSource = new InputSource(new InputStreamReader(
                                        new FileInputStream(filename), "UTF-16"));
                } catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                } catch (ParserConfigurationException e) {
                        e.printStackTrace();
                } catch (SAXException e) {
                        e.printStackTrace();
                } catch (FileNotFoundException e) {
                        e.printStackTrace();
                }
                if (inputSource != null) {
                        inputSource.setSystemId("file://"
                                        + new File(filename).getAbsolutePath());
                        try {
                                if (saxParser == null) {
                                        throw new RuntimeException("SAXParser creation failed");
                                }
                                saxParser.parse(inputSource, this);
                        } catch (SAXParseException e) {
                                Console.printerrln("Failure parsing file in line "
                                                + e.getLineNumber() + ", column " + e.getColumnNumber()
                                                + ".");
                                e.printStackTrace();
                        } catch (SAXException e) {
                                e.printStackTrace();
                        } catch (IOException e) {
                                e.printStackTrace();
                        }
                }
        }

}