src/main/java/org/apache/maven/plugins/changelog/ChangeLogHandler.java

/*
 * 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.maven.plugins.changelog;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Collection;
import java.util.Date;
import java.util.LinkedList;
import java.util.List;
import java.util.TimeZone;
import java.util.regex.Pattern;

import org.apache.maven.scm.ChangeFile;
import org.apache.maven.scm.ChangeSet;
import org.apache.maven.scm.ScmTag;
import org.apache.maven.scm.command.changelog.ChangeLogSet;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

/**
 * Change log generated xml parser.  SAXParser listener for processing a previously generated xml into several
 * change log sets.
 */
public class ChangeLogHandler extends DefaultHandler {
    // Use the same time zone offset when reading and adding times
    // It doesn't matter which one we use, as long we always use the same one
    private static final String TIMEZONE_STRING = "GMT-00:00";

    private static final TimeZone TIMEZONE = TimeZone.getTimeZone(TIMEZONE_STRING);

    private final Collection<ChangeLogSet> changeSets;

    private String bufData = "";

    private ChangeFile bufFile;

    private ChangeSet bufEntry;

    private List<ChangeSet> bufEntries;

    private ChangeLogSet bufSet;

    private String currentPattern;

    private final Pattern nameRegex = Pattern.compile(" \\(from [^:]+:\\d+\\)");

    /**
     * contructor
     *
     * @param changeSets collection object to store all change sets found within the xml document
     */
    public ChangeLogHandler(Collection<ChangeLogSet> changeSets) {
        this.changeSets = changeSets;
    }

    /**
     * {@inheritDoc}
     */
    public void characters(char[] ch, int start, int length) throws SAXException {
        bufData += new String(ch, start, length);
    }

    /**
     * {@inheritDoc}
     */
    public void endElement(String uri, String localName, String qName) throws SAXException {
        if ("changeset".equals(qName)) {
            changeSets.add(bufSet);
        }

        if ("changelog-entry".equals(qName)) {
            bufEntries.add(bufEntry);
        }

        if ("file".equals(qName)) {
            bufEntry.addFile(bufFile);
        } else if ("date".equals(qName)) {
            try {
                long ms = 0;
                if (bufEntry.getDate() != null) {
                    ms = bufEntry.getDate().getTime();
                }
                bufEntry.setDate(new Date(
                        ms + new SimpleDateFormat(currentPattern).parse(bufData).getTime()));
            } catch (ParseException e) {
                throw new SAXException(e);
            }
        } else if ("time".equals(qName)) {
            try {
                long ms = 0;
                if (bufEntry.getDate() != null) {
                    ms = bufEntry.getDate().getTime();
                }
                SimpleDateFormat simpleDateFormat = new SimpleDateFormat(currentPattern);
                // MCHANGELOG-68 Adjust for time zone when parsing the time
                simpleDateFormat.setTimeZone(TIMEZONE);
                // Adjust for time zone when adding up the milliseconds
                bufEntry.setDate(new Date(ms + simpleDateFormat.parse(bufData).getTime() + TIMEZONE.getRawOffset()));
            } catch (ParseException e) {
                throw new SAXException(e);
            }
        } else if ("author".equals(qName)) {
            bufEntry.setAuthor(bufData);
        } else if ("msg".equals(qName)) {
            bufEntry.setComment(bufData);
        }

        if ("revision".equals(qName)) {
            bufFile.setRevision(bufData);
        } else if ("name".equals(qName)) {
            bufFile.setName(nameRegex.matcher(bufData).replaceFirst(""));
        }
    }

    /**
     * {@inheritDoc}
     */
    public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
        bufData = "";

        if ("file".equals(qName)) {
            bufFile = new ChangeFile("");
        } else if ("changelog-entry".equals(qName)) {
            bufEntry = new ChangeSet();
        } else if ("date".equals(qName)) {
            currentPattern = attributes.getValue("pattern");
            if (currentPattern == null) {
                currentPattern = "yyyy-MM-dd";
            }
        } else if ("time".equals(qName)) {
            currentPattern = attributes.getValue("pattern");
            if (currentPattern == null) {
                currentPattern = "HH:mm:ss";
            }
        } else if ("changeset".equals(qName)) {
            bufEntries = new LinkedList<>();

            currentPattern = attributes.getValue("datePattern");
            if (currentPattern == null) {
                currentPattern = "yyyy-MM-dd";
            }

            SimpleDateFormat formatter = new SimpleDateFormat(currentPattern);

            String start = attributes.getValue("start");

            String end = attributes.getValue("end");

            Date startDate = null;

            Date endDate = null;

            if (start != null) {
                try {
                    startDate = formatter.parse(start);
                } catch (ParseException e) {
                    throw new SAXException("Can't parse start date '" + start + "'.", e);
                }
            }

            if (end != null) {
                try {
                    endDate = formatter.parse(end);
                } catch (ParseException e) {
                    throw new SAXException("Can't parse end date '" + end + "'.", e);
                }
            }

            bufSet = new ChangeLogSet(bufEntries, startDate, endDate);
            String startVersion = attributes.getValue("startVersion");
            if (startVersion != null) {
                bufSet.setStartVersion(new ScmTag(startVersion));
            }
            String endVersion = attributes.getValue("endVersion");
            if (endVersion != null) {
                bufSet.setEndVersion(new ScmTag(endVersion));
            }
        }
    }
}