1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2026 the original author or authors.
4 //
5 // This library is free software; you can redistribute it and/or
6 // modify it under the terms of the GNU Lesser General Public
7 // License as published by the Free Software Foundation; either
8 // version 2.1 of the License, or (at your option) any later version.
9 //
10 // This library is distributed in the hope that it will be useful,
11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 // Lesser General Public License for more details.
14 //
15 // You should have received a copy of the GNU Lesser General Public
16 // License along with this library; if not, write to the Free Software
17 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 ///////////////////////////////////////////////////////////////////////////////////////////////
19
20 package com.puppycrawl.tools.checkstyle.checks.regexp;
21
22 import java.util.regex.Matcher;
23
24 import com.puppycrawl.tools.checkstyle.api.FileText;
25 import com.puppycrawl.tools.checkstyle.api.LineColumn;
26
27 /**
28 * A detector that matches across multiple lines.
29 */
30 public class MultilineDetector {
31
32 /** The detection options to use. */
33 private final DetectorOptions options;
34 /** The message key for exceeded matches. */
35 private final String exceededMessage;
36 /** The message key for minimum matches not met. */
37 private final String minimumMessage;
38 /** The message key for empty format. */
39 private final String emptyMessage;
40 /** The message key for StackOverflow error. */
41 private final String stackOverflowMessage;
42 /** Tracks the number of matches. */
43 private int currentMatches;
44 /** The matcher. */
45 private Matcher matcher;
46 /** The file text content. */
47 private FileText text;
48
49 /**
50 * Creates an instance.
51 *
52 * @param options the options to use.
53 * @param exceededMessage the message key for exceeded matches.
54 * @param minimumMessage the message key for minimum matches not met.
55 * @param emptyMessage the message key for empty format.
56 * @param stackOverflowMessage the message key for StackOverflow error.
57 */
58 /* package */ MultilineDetector(DetectorOptions options,
59 String exceededMessage, String minimumMessage,
60 String emptyMessage, String stackOverflowMessage) {
61 this.options = options;
62 this.exceededMessage = exceededMessage;
63 this.minimumMessage = minimumMessage;
64 this.emptyMessage = emptyMessage;
65 this.stackOverflowMessage = stackOverflowMessage;
66 }
67
68 /**
69 * Processes an entire text file looking for matches.
70 *
71 * @param fileText the text to process
72 */
73 public void processLines(FileText fileText) {
74 text = new FileText(fileText);
75 resetState();
76
77 final String format = options.getFormat();
78 if (format == null || format.isEmpty()) {
79 options.getReporter().log(1, emptyMessage);
80 }
81 else {
82 matcher = options.getPattern().matcher(fileText.getFullText());
83 findMatch();
84 finish();
85 }
86 }
87
88 /** Method that finds the matches. */
89 private void findMatch() {
90 try {
91 boolean foundMatch = matcher.find();
92
93 while (foundMatch) {
94 currentMatches++;
95 if (currentMatches > options.getMaximum()) {
96 final LineColumn start = text.lineColumn(matcher.start());
97 if (options.getMessage().isEmpty()) {
98 options.getReporter().log(start.getLine(),
99 exceededMessage,
100 matcher.pattern().toString());
101 }
102 else {
103 options.getReporter()
104 .log(start.getLine(), options.getMessage());
105 }
106 }
107 foundMatch = matcher.find();
108 }
109 }
110 // see http://bugs.java.com/bugdatabase/view_bug.do?bug_id=6337993 et al.
111 catch (StackOverflowError ignored) {
112 // ok http://blog.igorminar.com/2008/05/catching-stackoverflowerror-and-bug-in.html
113 // http://programmers.stackexchange.com/questions/
114 // 209099/is-it-ever-okay-to-catch-stackoverflowerror-in-java
115 options.getReporter().log(1, stackOverflowMessage,
116 matcher.pattern().toString());
117 }
118 }
119
120 /** Perform processing at the end of a set of lines. */
121 private void finish() {
122 if (currentMatches < options.getMinimum()) {
123 if (options.getMessage().isEmpty()) {
124 options.getReporter().log(1, minimumMessage,
125 options.getMinimum(), options.getFormat());
126 }
127 else {
128 options.getReporter().log(1, options.getMessage());
129 }
130 }
131 }
132
133 /**
134 * Reset the state of the detector.
135 */
136 private void resetState() {
137 currentMatches = 0;
138 }
139
140 }