Source code

001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2022 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 com.puppycrawl.tools.checkstyle.PropertyType;
023import com.puppycrawl.tools.checkstyle.StatelessCheck;
024import com.puppycrawl.tools.checkstyle.XdocsPropertyType;
025import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
026import com.puppycrawl.tools.checkstyle.api.DetailAST;
027import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
028
029/**
030 * <p>
031 * Checks that a specified pattern matches a single line in Java files.
032 * </p>
033 * <p>
034 * This class is variation on
035 * <a href="https://checkstyle.org/config_regexp.html#RegexpSingleline">RegexpSingleline</a>
036 * for detecting single lines that match a supplied regular expression in Java files.
037 * It supports suppressing matches in Java comments.
038 * </p>
039 * <ul>
040 * <li>
041 * Property {@code format} - Specify the format of the regular expression to match.
042 * Type is {@code java.util.regex.Pattern}.
043 * Default value is {@code "$."}.
044 * </li>
045 * <li>
046 * Property {@code message} - Specify the message which is used to notify about
047 * violations, if empty then default (hard-coded) message is used.
048 * Type is {@code java.lang.String}.
049 * Default value is {@code null}.
050 * </li>
051 * <li>
052 * Property {@code ignoreCase} - Control whether to ignore case when searching.
053 * Type is {@code boolean}.
054 * Default value is {@code false}.
055 * </li>
056 * <li>
057 * Property {@code minimum} - Specify the minimum number of matches required in each file.
058 * Type is {@code int}.
059 * Default value is {@code 0}.
060 * </li>
061 * <li>
062 * Property {@code maximum} - Specify the maximum number of matches required in each file.
063 * Type is {@code int}.
064 * Default value is {@code 0}.
065 * </li>
066 * <li>
067 * Property {@code ignoreComments} - Control whether to ignore text in comments when searching.
068 * Type is {@code boolean}.
069 * Default value is {@code false}.
070 * </li>
071 * </ul>
072 * <p>
073 *   To configure the default check:
074 * </p>
075 * <pre>
076 * &lt;module name=&quot;RegexpSinglelineJava&quot;/&gt;
077 * </pre>
078 * <p>
079 *   This configuration does not match to anything,
080 *   so we do not provide any code example for it
081 *   as no violation will ever be reported.
082 * </p>
083 * <p>
084 * To configure the check for calls to {@code System.out.println}, except in comments:
085 * </p>
086 * <pre>
087 * &lt;module name="RegexpSinglelineJava"&gt;
088 *   &lt;!-- . matches any character, so we need to
089 *        escape it and use \. to match dots. --&gt;
090 *   &lt;property name="format" value="System\.out\.println"/&gt;
091 *   &lt;property name="ignoreComments" value="true"/&gt;
092 * &lt;/module&gt;
093 * </pre>
094 * <p>Example:</p>
095 * <pre>
096 * System.out.println(""); // violation, instruction matches illegal pattern
097 * System.out.
098 *   println(""); // OK
099 * &#47;* System.out.println *&#47; // OK, comments are ignored
100 * </pre>
101 * <p>
102 * To configure the check to find case-insensitive occurrences of "debug":
103 * </p>
104 * <pre>
105 * &lt;module name="RegexpSinglelineJava"&gt;
106 *   &lt;property name="format" value="debug"/&gt;
107 *   &lt;property name="ignoreCase" value="true"/&gt;
108 * &lt;/module&gt;
109 * </pre>
110 * <p>Example:</p>
111 * <pre>
112 * int debug = 0; // violation, variable name matches illegal pattern
113 * public class Debug { // violation, class name matches illegal pattern
114 * &#47;* this is for de
115 *   bug only; *&#47; // OK
116 * </pre>
117 * <p>
118 * To configure the check to find occurrences of
119 * &quot;\.read(.*)|\.write(.*)&quot;
120 * and display &quot;IO found&quot; for each violation.
121 * </p>
122 * <pre>
123 * &lt;module name=&quot;RegexpSinglelineJava&quot;&gt;
124 *   &lt;property name=&quot;format&quot; value=&quot;\.read(.*)|\.write(.*)&quot;/&gt;
125 *   &lt;property name=&quot;message&quot; value=&quot;IO found&quot;/&gt;
126 * &lt;/module&gt;
127 * </pre>
128 * <p>Example:</p>
129 * <pre>
130 * FileReader in = new FileReader("path/to/input");
131 * int ch = in.read(); // violation
132 * while(ch != -1) {
133 *   System.out.print((char)ch);
134 *   ch = in.read(); // violation
135 * }
136 *
137 * FileWriter out = new FileWriter("path/to/output");
138 * out.write("something"); // violation
139 * </pre>
140 * <p>
141 * To configure the check to find occurrences of
142 * &quot;\.log(.*)&quot;. We want to allow a maximum of 2 occurrences.
143 * </p>
144 * <pre>
145 * &lt;module name=&quot;RegexpSinglelineJava&quot;&gt;
146 *   &lt;property name=&quot;format&quot; value=&quot;\.log(.*)&quot;/&gt;
147 *   &lt;property name=&quot;maximum&quot; value=&quot;2&quot;/&gt;
148 * &lt;/module&gt;
149 * </pre>
150 * <p>Example:</p>
151 * <pre>
152 * public class Foo{
153 *   public void bar(){
154 *     Logger.log("first"); // OK, first occurrence is allowed
155 *     Logger.log("second"); // OK, second occurrence is allowed
156 *     Logger.log("third"); // violation
157 *     System.out.println("fourth");
158 *     Logger.log("fifth"); // violation
159 *   }
160 * }
161 * </pre>
162 * <p>
163 * To configure the check to find all occurrences of
164 * &quot;public&quot;. We want to ignore comments,
165 * display &quot;public member found&quot; for each violation
166 * and say if less than 2 occurrences.
167 * </p>
168 * <pre>
169 * &lt;module name=&quot;RegexpSinglelineJava&quot;&gt;
170 *   &lt;property name=&quot;format&quot; value=&quot;public&quot;/&gt;
171 *   &lt;property name=&quot;minimum&quot; value=&quot;2&quot;/&gt;
172 *   &lt;property name=&quot;message&quot; value=&quot;public member found&quot;/&gt;
173 *   &lt;property name=&quot;ignoreComments&quot; value=&quot;true&quot;/&gt;
174 * &lt;/module&gt;
175 * </pre>
176 * <p>Example:</p>
177 * <pre>
178 * class Foo{ // violation, file contains less than 2 occurrences of "public"
179 *   private int a;
180 *   &#47;* public comment *&#47; // OK, comment is ignored
181 *   private void bar1() {}
182 *   public void bar2() {} // violation
183 * }
184 * </pre>
185 * <p>Example:</p>
186 * <pre>
187 * class Foo{
188 *   private int a;
189 *  &#47;* public comment *&#47; // OK, comment is ignored
190 *   public void bar1() {} // violation
191 *   public void bar2() {} // violation
192 * }
193 * </pre>
194 * <p>
195 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
196 * </p>
197 * <p>
198 * Violation Message Keys:
199 * </p>
200 * <ul>
201 * <li>
202 * {@code regexp.exceeded}
203 * </li>
204 * <li>
205 * {@code regexp.minimum}
206 * </li>
207 * </ul>
208 *
209 * @since 6.0
210 */
211@StatelessCheck
212public class RegexpSinglelineJavaCheck extends AbstractCheck {
213
214    /** Specify the format of the regular expression to match. */
215    @XdocsPropertyType(PropertyType.PATTERN)
216    private String format = "$.";
217    /**
218     * Specify the message which is used to notify about violations,
219     * if empty then default (hard-coded) message is used.
220     */
221    private String message;
222    /** Specify the minimum number of matches required in each file. */
223    private int minimum;
224    /** Specify the maximum number of matches required in each file. */
225    private int maximum;
226    /** Control whether to ignore case when searching. */
227    private boolean ignoreCase;
228    /** Control whether to ignore text in comments when searching. */
229    private boolean ignoreComments;
230
231    @Override
232    public int[] getDefaultTokens() {
233        return getRequiredTokens();
234    }
235
236    @Override
237    public int[] getAcceptableTokens() {
238        return getRequiredTokens();
239    }
240
241    @Override
242    public int[] getRequiredTokens() {
243        return CommonUtil.EMPTY_INT_ARRAY;
244    }
245
246    // suppress deprecation until https://github.com/checkstyle/checkstyle/issues/11166
247    @SuppressWarnings("deprecation")
248    @Override
249    public void beginTree(DetailAST rootAST) {
250        MatchSuppressor suppressor = null;
251        if (ignoreComments) {
252            suppressor = new CommentSuppressor(getFileContents());
253        }
254
255        final DetectorOptions options = DetectorOptions.newBuilder()
256            .reporter(this)
257            .compileFlags(0)
258            .suppressor(suppressor)
259            .format(format)
260            .message(message)
261            .minimum(minimum)
262            .maximum(maximum)
263            .ignoreCase(ignoreCase)
264            .build();
265        final SinglelineDetector detector = new SinglelineDetector(options);
266        detector.processLines(getFileContents().getText());
267    }
268
269    /**
270     * Setter to specify the format of the regular expression to match.
271     *
272     * @param format the format of the regular expression to match.
273     */
274    public void setFormat(String format) {
275        this.format = format;
276    }
277
278    /**
279     * Setter to specify the message which is used to notify about violations,
280     * if empty then default (hard-coded) message is used.
281     *
282     * @param message the message to report for a match.
283     */
284    public void setMessage(String message) {
285        this.message = message;
286    }
287
288    /**
289     * Setter to specify the minimum number of matches required in each file.
290     *
291     * @param minimum the minimum number of matches required in each file.
292     */
293    public void setMinimum(int minimum) {
294        this.minimum = minimum;
295    }
296
297    /**
298     * Setter to specify the maximum number of matches required in each file.
299     *
300     * @param maximum the maximum number of matches required in each file.
301     */
302    public void setMaximum(int maximum) {
303        this.maximum = maximum;
304    }
305
306    /**
307     * Setter to control whether to ignore case when searching.
308     *
309     * @param ignoreCase whether to ignore case when searching.
310     */
311    public void setIgnoreCase(boolean ignoreCase) {
312        this.ignoreCase = ignoreCase;
313    }
314
315    /**
316     * Setter to control whether to ignore text in comments when searching.
317     *
318     * @param ignore whether to ignore text in comments when searching.
319     */
320    public void setIgnoreComments(boolean ignore) {
321        ignoreComments = ignore;
322    }
323
324}