001    package org.apache.maven.scm.provider.git.gitexe.command.update;
002    
003    /*
004     * Licensed to the Apache Software Foundation (ASF) under one
005     * or more contributor license agreements.  See the NOTICE file
006     * distributed with this work for additional information
007     * regarding copyright ownership.  The ASF licenses this file
008     * to you under the Apache License, Version 2.0 (the
009     * "License"); you may not use this file except in compliance
010     * with the License.  You may obtain a copy of the License at
011     *
012     *   http://www.apache.org/licenses/LICENSE-2.0
013     *
014     * Unless required by applicable law or agreed to in writing,
015     * software distributed under the License is distributed on an
016     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017     * KIND, either express or implied.  See the License for the
018     * specific language governing permissions and limitations
019     * under the License.
020     */
021    
022    import org.apache.maven.scm.log.ScmLogger;
023    import org.apache.maven.scm.util.AbstractConsumer;
024    import org.apache.regexp.RE;
025    import org.apache.regexp.RESyntaxException;
026    import org.codehaus.plexus.util.StringUtils;
027    
028    /**
029     * @author <a href="mailto:struberg@yahoo.de">Mark Struberg</a>
030     *
031     */
032    public class GitLatestRevisionCommandConsumer
033        extends AbstractConsumer
034    {
035    
036        /**
037         * The pattern used to match git log latest revision lines
038         */
039        private static final String LATESTREV_PATTERN = "^commit \\s*(.*)";
040    
041        /**
042         * The regular expression used to match git log latest revision lines
043         */
044        private RE latestRevRegexp;
045    
046        private String latestRevision;
047    
048        public GitLatestRevisionCommandConsumer( ScmLogger logger )
049        {
050            super( logger );
051    
052            try
053            {
054                latestRevRegexp = new RE( LATESTREV_PATTERN );
055            }
056            catch ( RESyntaxException ex )
057            {
058                throw new RuntimeException( "INTERNAL ERROR: Could not create regexp to parse git log file. This shouldn't happen. "
059                                            + "Something is probably wrong with the oro installation.",
060                                            ex );
061            }
062    
063        }
064    
065        /** {@inheritDoc} */
066        public void consumeLine( String line )
067        {
068            if ( getLogger().isDebugEnabled() )
069            {
070                getLogger().debug( "GitLatestRevisionCommandConsumer consumeLine : " + line );
071            }
072            if ( line == null || StringUtils.isEmpty( line ) )
073            {
074                return;
075            }
076    
077            processGetLatestRevision( line );
078        }
079    
080        public String getLatestRevision()
081        {
082            return latestRevision;
083        }
084    
085        /**
086         * Process the current input line for the latest revision
087         *
088         * @param line A line of text from the git log output
089         */
090        private void processGetLatestRevision( String line )
091        {
092            if ( !latestRevRegexp.match( line ) )
093            {
094                return;
095            }
096    
097            latestRevision = latestRevRegexp.getParen( 1 );
098        }
099    
100    }