1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2024 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.javadoc.utils;
21
22 import java.util.ArrayList;
23 import java.util.List;
24 import java.util.regex.Matcher;
25 import java.util.regex.Pattern;
26
27 import com.puppycrawl.tools.checkstyle.api.LineColumn;
28
29 /**
30 * Tools for parsing block tags from a Javadoc comment.
31 *
32 */
33 public final class BlockTagUtil {
34
35 /** Block tag pattern for a first line. */
36 private static final Pattern BLOCK_TAG_PATTERN_FIRST_LINE = Pattern.compile(
37 "/\\*{2,}\\s*@(\\p{Alpha}+)\\s");
38
39 /** Block tag pattern. */
40 private static final Pattern BLOCK_TAG_PATTERN = Pattern.compile(
41 "^\\s*\\**\\s*@(\\p{Alpha}+)\\s");
42
43 /** Closing tag. */
44 private static final String JAVADOC_CLOSING_TAG = "*/";
45
46 /** Prevent instantiation. */
47 private BlockTagUtil() {
48 }
49
50 /**
51 * Extract the block tags from a Javadoc comment.
52 *
53 * @param lines The text of the comment, as separate lines.
54 * @return The tags extracted from the block.
55 */
56 public static List<TagInfo> extractBlockTags(String... lines) {
57 final List<TagInfo> tags = new ArrayList<>();
58
59 for (int i = 0; i < lines.length; i++) {
60 // Starting lines of a comment have a different first line pattern.
61 final boolean isFirstLine = i == 0;
62 final Pattern pattern;
63 if (isFirstLine) {
64 pattern = BLOCK_TAG_PATTERN_FIRST_LINE;
65 }
66 else {
67 pattern = BLOCK_TAG_PATTERN;
68 }
69
70 final String line = lines[i];
71 final Matcher tagMatcher = pattern.matcher(line);
72
73 if (tagMatcher.find()) {
74 final String tagName = tagMatcher.group(1);
75
76 // offset of one for the @ character
77 final int colNum = tagMatcher.start(1) - 1;
78 final int lineNum = i + 1;
79
80 final String remainder = line.substring(tagMatcher.end(1));
81 String tagValue = remainder.trim();
82
83 // Handle the case where we're on the last line of a Javadoc comment.
84 if (tagValue.endsWith(JAVADOC_CLOSING_TAG)) {
85 final int endIndex = tagValue.length() - JAVADOC_CLOSING_TAG.length();
86 tagValue = tagValue.substring(0, endIndex).trim();
87 }
88
89 final LineColumn position = new LineColumn(lineNum, colNum);
90 tags.add(new TagInfo(tagName, tagValue, position));
91 }
92 }
93
94 return tags;
95 }
96
97 }