Source code

001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2020 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;
023
024import com.puppycrawl.tools.checkstyle.StatelessCheck;
025import com.puppycrawl.tools.checkstyle.api.AbstractFileSetCheck;
026import com.puppycrawl.tools.checkstyle.api.FileText;
027
028/**
029 * <p>
030 * Checks that a specified pattern matches a single line in any file type.
031 * </p>
032 * <p>
033 * Rationale: This check can be used to prototype checks and to find common bad
034 * practice such as calling {@code ex.printStacktrace()},
035 * {@code System.out.println()}, {@code System.exit()}, etc.
036 * </p>
037 * <ul>
038 * <li>
039 * Property {@code format} - Specify the format of the regular expression to match.
040 * Default value is {@code "$."}.
041 * </li>
042 * <li>
043 * Property {@code message} - Specify the message which is used to notify about
044 * violations, if empty then default (hard-coded) message is used.
045 * Default value is {@code null}.
046 * </li>
047 * <li>
048 * Property {@code ignoreCase} - Control whether to ignore case when searching.
049 * Default value is {@code false}.
050 * </li>
051 * <li>
052 * Property {@code minimum} - Specify the minimum number of matches required in each file.
053 * Default value is {@code 0}.
054 * </li>
055 * <li>
056 * Property {@code maximum} - Specify the maximum number of matches required in each file.
057 * Default value is {@code 0}.
058 * </li>
059 * <li>
060 * Property {@code fileExtensions} - Specify the file type extension of files to process.
061 * Default value is {@code all files}.
062 * </li>
063 * </ul>
064 * <p>
065 *   To configure the check with default values:
066 * </p>
067 * <pre>
068 * &lt;module name="RegexpSingleline" /&gt;
069 * </pre>
070 * <p>
071 *   This configuration does not match to anything,
072 *   so we do not provide any code example for it
073 *   as no violation will ever be reported.
074 * </p>
075 * <p>
076 * To configure the check to find occurrences of 'System.exit('
077 * with some <i>slack</i> of allowing only one occurrence per file:
078 * </p>
079 * <pre>
080 * &lt;module name="RegexpSingleline"&gt;
081 *   &lt;property name="format" value="System.exit\("/&gt;
082 *   &lt;!-- next line not required as 0 is the default --&gt;
083 *   &lt;property name="minimum" value="0"/&gt;
084 *   &lt;property name="maximum" value="1"/&gt;
085 * &lt;/module&gt;
086 * </pre>
087 * <p>Example:</p>
088 * <pre>
089 * class MyClass {
090 *      void myFunction() {
091 *          try {
092 *             doSomething();
093 *          } catch (Exception e) {
094 *             System.exit(1); // OK, as only there is only one occurrence.
095 *          }
096 *      }
097 *      void doSomething(){};
098 * }
099 * </pre>
100 * <pre>
101 * class MyClass {
102 *     void myFunction() {
103 *         try {
104 *             doSomething();
105 *             System.exit(0);
106 *         } catch (Exception e) {
107 *             System.exit(1); // Violation, as there are more than one occurrence.
108 *         }
109 *     }
110 *     void doSomething(){};
111 * }
112 * </pre>
113 * <p>
114 * An example of how to configure the check to make sure a copyright statement
115 * is included in the file:
116 * </p>
117 * <pre>
118 * &lt;module name="RegexpSingleline"&gt;
119 *   &lt;property name="format" value="This file is copyrighted"/&gt;
120 *   &lt;property name="minimum" value="1"/&gt;
121 *   &lt;!--  Need to specify a maximum, so 10 times is more than enough. --&gt;
122 *   &lt;property name="maximum" value="10"/&gt;
123 * &lt;/module&gt;
124 * </pre>
125 * <p>Example:</p>
126 * <pre>
127 * &#47;**
128 * * This file is copyrighted under CC. // Ok, as the file contains a copyright statement.
129 * *&#47;
130 * class MyClass {
131 *
132 * }
133 * </pre>
134 * <pre>
135 * &#47;** // violation, as the file doesn't contain a copyright statement.
136 * * MyClass as a configuration example.
137 * *&#47;
138 * class MyClass {
139 *
140 * }
141 * </pre>
142 * <p>
143 *  An example of how to configure the check to make sure sql files contains the term 'license'.
144 * </p>
145 * <pre>
146 * &lt;module name="RegexpSingleline"&gt;
147 *     &lt;property name="format" value="license"/&gt;
148 *     &lt;property name="minimum" value="1"/&gt;
149 *     &lt;property name="maximum" value="9999"/&gt;
150 *     &lt;property name="ignoreCase" value="true"/&gt;
151 *     &lt;!--  Configure a message to be shown on violation of the Check. --&gt;
152 *     &lt;property name="message"
153 *           value="File must contain at least one occurrence of 'license' term"/&gt;
154*      &lt;!--  Perform the Check only on files with java extension. --&gt;
155 *     &lt;property name="fileExtensions" value="sql"/&gt;
156 * &lt;/module&gt;
157 * </pre>
158 * <p>Example:</p>
159 * <pre>
160 * &#47;*
161 * AP 2.0 License. // Ok, Check ignores the case of the term.
162 * *&#47;
163 * CREATE DATABASE MyDB;
164 * </pre>
165 * <pre>
166 * &#47;* // violation, file doesn't contain the term.
167 * Example sql file.
168 * *&#47;
169 * CREATE DATABASE MyDB;
170 * </pre>
171 *
172 * @since 5.0
173 */
174@StatelessCheck
175public class RegexpSinglelineCheck extends AbstractFileSetCheck {
176
177    /** Specify the format of the regular expression to match. */
178    private String format = "$.";
179    /**
180     * Specify the message which is used to notify about violations,
181     * if empty then default (hard-coded) message is used.
182     */
183    private String message;
184    /** Specify the minimum number of matches required in each file. */
185    private int minimum;
186    /** Specify the maximum number of matches required in each file. */
187    private int maximum;
188    /** Control whether to ignore case when searching. */
189    private boolean ignoreCase;
190
191    /** The detector to use. */
192    private SinglelineDetector detector;
193
194    @Override
195    public void beginProcessing(String charset) {
196        final DetectorOptions options = DetectorOptions.newBuilder()
197            .reporter(this)
198            .compileFlags(0)
199            .format(format)
200            .message(message)
201            .minimum(minimum)
202            .maximum(maximum)
203            .ignoreCase(ignoreCase)
204            .build();
205        detector = new SinglelineDetector(options);
206    }
207
208    @Override
209    protected void processFiltered(File file, FileText fileText) {
210        detector.processLines(fileText);
211    }
212
213    /**
214     * Setter to specify the format of the regular expression to match.
215     *
216     * @param format the format of the regular expression to match.
217     */
218    public void setFormat(String format) {
219        this.format = format;
220    }
221
222    /**
223     * Setter to specify the message which is used to notify about violations,
224     * if empty then default (hard-coded) message is used.
225     *
226     * @param message the message to report for a match.
227     */
228    public void setMessage(String message) {
229        this.message = message;
230    }
231
232    /**
233     * Setter to specify the minimum number of matches required in each file.
234     *
235     * @param minimum the minimum number of matches required in each file.
236     */
237    public void setMinimum(int minimum) {
238        this.minimum = minimum;
239    }
240
241    /**
242     * Setter to specify the maximum number of matches required in each file.
243     *
244     * @param maximum the maximum number of matches required in each file.
245     */
246    public void setMaximum(int maximum) {
247        this.maximum = maximum;
248    }
249
250    /**
251     * Setter to control whether to ignore case when searching.
252     *
253     * @param ignoreCase whether to ignore case when searching.
254     */
255    public void setIgnoreCase(boolean ignoreCase) {
256        this.ignoreCase = ignoreCase;
257    }
258
259}