001///////////////////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
003// Copyright (C) 2001-2024 the original author or authors.
004//
005// This library is free software; you can redistribute it and/or
006// modify it under the terms of the GNU Lesser General Public
007// License as published by the Free Software Foundation; either
008// version 2.1 of the License, or (at your option) any later version.
009//
010// This library is distributed in the hope that it will be useful,
011// but WITHOUT ANY WARRANTY; without even the implied warranty of
012// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
013// Lesser General Public License for more details.
014//
015// You should have received a copy of the GNU Lesser General Public
016// License along with this library; if not, write to the Free Software
017// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
018///////////////////////////////////////////////////////////////////////////////////////////////
019
020package com.puppycrawl.tools.checkstyle.checks.regexp;
021
022import java.util.regex.Matcher;
023
024import com.puppycrawl.tools.checkstyle.api.FileText;
025
026/**
027 * A detector that matches individual lines.
028 */
029class SinglelineDetector {
030
031    /**
032     * A key is pointing to the warning message text in "messages.properties"
033     * file.
034     */
035    public static final String MSG_REGEXP_EXCEEDED = "regexp.exceeded";
036
037    /**
038     * A key is pointing to the warning message text in "messages.properties"
039     * file.
040     */
041    public static final String MSG_REGEXP_MINIMUM = "regexp.minimum";
042
043    /**
044     * The detection options to use.
045     */
046    private final DetectorOptions options;
047    /**
048     * Tracks the number of matches.
049     */
050    private int currentMatches;
051
052    /**
053     * Creates an instance.
054     *
055     * @param options the options to use.
056     */
057    /* package */ SinglelineDetector(DetectorOptions options) {
058        this.options = options;
059    }
060
061    /**
062     * Processes a set of lines looking for matches.
063     *
064     * @param fileText {@link FileText} object contains the lines to process.
065     */
066    public void processLines(FileText fileText) {
067        currentMatches = 0;
068        int lineNo = 0;
069        for (int index = 0; index < fileText.size(); index++) {
070            final String line = fileText.get(index);
071            lineNo++;
072            checkLine(lineNo, options.getPattern().matcher(line));
073        }
074        finish();
075    }
076
077    /**
078     * Perform processing at the end of a set of lines.
079     */
080    private void finish() {
081        if (currentMatches < options.getMinimum()) {
082            if (options.getMessage().isEmpty()) {
083                options.getReporter().log(1, MSG_REGEXP_MINIMUM,
084                        options.getMinimum(), options.getFormat());
085            }
086            else {
087                options.getReporter().log(1, options.getMessage());
088            }
089        }
090    }
091
092    /**
093     * Check a line for matches.
094     *
095     * @param lineNo        the line number of the line to check
096     * @param matcher       the matcher to use
097     */
098    private void checkLine(int lineNo, Matcher matcher) {
099        int startPosition = 0;
100        while (matcher.find(startPosition)) {
101            // match is found, check for intersection with comment
102            final int startCol = matcher.start(0);
103            final int endCol = matcher.end(0);
104            // Note that Matcher.end(int) returns the offset AFTER the
105            // last matched character, but shouldSuppress()
106            // needs column number of the last character.
107            // So we need to use (endCol - 1) here.
108
109            if (options.getSuppressor()
110                    .shouldSuppress(lineNo, startCol, lineNo, endCol - 1)) {
111                startPosition = endCol;
112            }
113            else {
114                currentMatches++;
115                if (currentMatches > options.getMaximum()) {
116                    if (options.getMessage().isEmpty()) {
117                        options.getReporter().log(lineNo, MSG_REGEXP_EXCEEDED,
118                                matcher.pattern().toString());
119                    }
120                    else {
121                        options.getReporter().log(lineNo, options.getMessage());
122                    }
123                }
124                break;
125            }
126        }
127    }
128}