001///////////////////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
003// Copyright (C) 2001-2026 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.io.File;
023import java.util.regex.Pattern;
024
025import com.puppycrawl.tools.checkstyle.PropertyType;
026import com.puppycrawl.tools.checkstyle.StatelessCheck;
027import com.puppycrawl.tools.checkstyle.XdocsPropertyType;
028import com.puppycrawl.tools.checkstyle.api.AbstractFileSetCheck;
029import com.puppycrawl.tools.checkstyle.api.FileText;
030
031/**
032 * <div>
033 * Checks that a specified pattern matches across multiple lines in any file type.
034 * </div>
035 *
036 * <p>
037 * Rationale: This check can be used to when the regular expression can be span multiple lines.
038 * </p>
039 *
040 * @since 5.0
041 */
042@StatelessCheck
043public class RegexpMultilineCheck extends AbstractFileSetCheck {
044
045    /** Specify the format of the regular expression to match. */
046    @XdocsPropertyType(PropertyType.PATTERN)
047    private String format = "$.";
048    /**
049     * Specify the message which is used to notify about violations,
050     * if empty then default (hard-coded) message is used.
051     */
052    private String message;
053    /** Specify the minimum number of matches required in each file. */
054    private int minimum;
055    /** Specify the maximum number of matches required in each file. */
056    private int maximum;
057    /** Control whether to ignore case when searching. */
058    private boolean ignoreCase;
059    /** Control whether to match expressions across multiple lines. */
060    private boolean matchAcrossLines;
061    /** Specify which capturing group to use for violation reporting. */
062    private int reportGroup;
063
064    /** The detector to use. */
065    private MultilineDetector detector;
066
067    @Override
068    public void beginProcessing(String charset) {
069        final DetectorOptions options = DetectorOptions.newBuilder()
070            .reporter(this)
071            .compileFlags(getRegexCompileFlags())
072            .format(format)
073            .message(message)
074            .minimum(minimum)
075            .maximum(maximum)
076            .ignoreCase(ignoreCase)
077            .reportGroup(reportGroup)
078            .build();
079        detector = new MultilineDetector(options);
080    }
081
082    @Override
083    protected void processFiltered(File file, FileText fileText) {
084        detector.processLines(fileText);
085    }
086
087    /**
088     * Retrieves the compile-flags for the regular expression being built based
089     * on {@code matchAcrossLines}.
090     *
091     * @return The compile-flags.
092     */
093    private int getRegexCompileFlags() {
094        final int result;
095
096        if (matchAcrossLines) {
097            result = Pattern.DOTALL;
098        }
099        else {
100            result = Pattern.MULTILINE;
101        }
102
103        return result;
104    }
105
106    /**
107     * Setter to specify the format of the regular expression to match.
108     *
109     * @param format the format of the regular expression to match.
110     * @since 5.0
111     */
112    public void setFormat(String format) {
113        this.format = format;
114    }
115
116    /**
117     * Setter to specify the message which is used to notify about violations,
118     * if empty then default (hard-coded) message is used.
119     *
120     * @param message the message to report for a match.
121     * @since 5.0
122     */
123    public void setMessage(String message) {
124        this.message = message;
125    }
126
127    /**
128     * Setter to specify the minimum number of matches required in each file.
129     *
130     * @param minimum the minimum number of matches required in each file.
131     * @since 5.0
132     */
133    public void setMinimum(int minimum) {
134        this.minimum = minimum;
135    }
136
137    /**
138     * Setter to specify the maximum number of matches required in each file.
139     *
140     * @param maximum the maximum number of matches required in each file.
141     * @since 5.0
142     */
143    public void setMaximum(int maximum) {
144        this.maximum = maximum;
145    }
146
147    /**
148     * Setter to control whether to ignore case when searching.
149     *
150     * @param ignoreCase whether to ignore case when searching.
151     * @since 5.0
152     */
153    public void setIgnoreCase(boolean ignoreCase) {
154        this.ignoreCase = ignoreCase;
155    }
156
157    /**
158     * Setter to control whether to match expressions across multiple lines.
159     *
160     * @param matchAcrossLines whether to match expressions across multiple lines.
161     * @since 8.25
162     */
163    public void setMatchAcrossLines(boolean matchAcrossLines) {
164        this.matchAcrossLines = matchAcrossLines;
165    }
166
167    /**
168     * Setter to specify which capturing group to use for violation reporting.
169     *
170     * @param reportGroup the capturing group number to use (0 for entire match).
171     * @since 13.3.0
172     */
173    public void setReportGroup(int reportGroup) {
174        this.reportGroup = reportGroup;
175    }
176
177}