001    /*
002     * Sonar, open source software quality management tool.
003     * Copyright (C) 2009 SonarSource SA
004     * mailto:contact AT sonarsource DOT com
005     *
006     * Sonar is free software; you can redistribute it and/or
007     * modify it under the terms of the GNU Lesser General Public
008     * License as published by the Free Software Foundation; either
009     * version 3 of the License, or (at your option) any later version.
010     *
011     * Sonar is distributed in the hope that it will be useful,
012     * but WITHOUT ANY WARRANTY; without even the implied warranty of
013     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014     * Lesser General Public License for more details.
015     *
016     * You should have received a copy of the GNU Lesser General Public
017     * License along with Sonar; if not, write to the Free Software
018     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019     */
020    package org.sonar.squid.text;
021    
022    public class SingleLineCommentHandler extends LineContextHandler {
023    
024      private StringBuilder comment;
025    
026      private final String commentStartTag;
027      private final String commentNotStartTag;
028    
029      public SingleLineCommentHandler(String commentStartTag) {
030        this(commentStartTag, null);
031      }
032    
033      public SingleLineCommentHandler(String commentStartTag, String commentNotStartTag) {
034        this.commentStartTag = commentStartTag;
035        this.commentNotStartTag = commentNotStartTag;
036      }
037    
038      @Override
039      boolean matchToEnd(Line line, StringBuilder pendingLine) {
040        if (comment == null) {
041          throw new IllegalStateException("Method doContextBegin(StringBuilder pendingLine) has not been called.");
042        }
043        comment.append(getLastCharacter(pendingLine));
044        return false;
045      }
046    
047      @Override
048      boolean matchToBegin(Line line, StringBuilder pendingLine) {
049        boolean doContextBegin = matchEndOfString(pendingLine, commentStartTag)
050            && (commentNotStartTag == null || !matchEndOfString(pendingLine, commentNotStartTag));
051        if (doContextBegin) {
052          comment = new StringBuilder(commentStartTag);
053        }
054        return doContextBegin;
055      }
056    
057      @Override
058      boolean matchWithEndOfLine(Line line, StringBuilder pendingLine) {
059        line.setComment(comment.toString());
060        comment = null;
061        return true;
062      }
063    }