1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2025 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.header;
21
22 import java.io.File;
23 import java.util.BitSet;
24
25 import com.puppycrawl.tools.checkstyle.StatelessCheck;
26 import com.puppycrawl.tools.checkstyle.api.FileText;
27 import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
28
29 /**
30 * <div>
31 * Checks that a source file begins with a specified header.
32 * Property {@code headerFile} specifies a file that contains the required header.
33 * Alternatively, the header specification can be set directly in the
34 * {@code header} property without the need for an external file.
35 * </div>
36 *
37 * <p>
38 * In default configuration, if header is not specified, the default value
39 * of header is set to {@code null} and the check does not rise any violations.
40 * </p>
41 * <ul>
42 * <li>
43 * Property {@code charset} - Specify the character encoding to use when reading the headerFile.
44 * Type is {@code java.lang.String}.
45 * Default value is {@code the charset property of the parent
46 * <a href="https://checkstyle.org/config.html#Checker">Checker</a> module}.
47 * </li>
48 * <li>
49 * Property {@code fileExtensions} - Specify the file extensions of the files to process.
50 * Type is {@code java.lang.String[]}.
51 * Default value is {@code ""}.
52 * </li>
53 * <li>
54 * Property {@code header} - Specify the required header specified inline.
55 * Individual header lines must be separated by the string {@code "\n"}
56 * (even on platforms with a different line separator).
57 * Type is {@code java.lang.String}.
58 * Default value is {@code null}.
59 * </li>
60 * <li>
61 * Property {@code headerFile} - Specify the name of the file containing the required header.
62 * Type is {@code java.net.URI}.
63 * Default value is {@code null}.
64 * </li>
65 * <li>
66 * Property {@code ignoreLines} - Specifies the line
67 * numbers to ignore when matching lines in a content of headerFile.
68 * Type is {@code int[]}.
69 * Default value is {@code ""}.
70 * </li>
71 * </ul>
72 *
73 * <p>
74 * Parent is {@code com.puppycrawl.tools.checkstyle.Checker}
75 * </p>
76 *
77 * <p>
78 * Violation Message Keys:
79 * </p>
80 * <ul>
81 * <li>
82 * {@code header.mismatch}
83 * </li>
84 * <li>
85 * {@code header.missing}
86 * </li>
87 * </ul>
88 *
89 * @since 3.2
90 */
91 @StatelessCheck
92 public class HeaderCheck extends AbstractHeaderCheck {
93
94 /**
95 * A key is pointing to the warning message text in "messages.properties"
96 * file.
97 */
98 public static final String MSG_MISSING = "header.missing";
99
100 /**
101 * A key is pointing to the warning message text in "messages.properties"
102 * file.
103 */
104 public static final String MSG_MISMATCH = "header.mismatch";
105
106 /** Specifies the line numbers to ignore when matching lines in a content of headerFile. */
107 private BitSet ignoreLines = new BitSet();
108
109 /**
110 * Returns true if lineNo is header lines or false.
111 *
112 * @param lineNo a line number
113 * @return if {@code lineNo} is one of the ignored header lines.
114 */
115 private boolean isIgnoreLine(int lineNo) {
116 return ignoreLines.get(lineNo);
117 }
118
119 /**
120 * Checks if a code line matches the required header line.
121 *
122 * @param lineNumber the line number to check against the header
123 * @param line the line contents
124 * @return true if and only if the line matches the required header line
125 */
126 private boolean isMatch(int lineNumber, String line) {
127 // skip lines we are meant to ignore
128 return isIgnoreLine(lineNumber + 1)
129 || getHeaderLines().get(lineNumber).equals(line);
130 }
131
132 /**
133 * Setter to specifies the line numbers
134 * to ignore when matching lines in a content of headerFile.
135 *
136 * @param lines line numbers to ignore in header.
137 * @since 3.2
138 */
139 public void setIgnoreLines(int... lines) {
140 ignoreLines = TokenUtil.asBitSet(lines);
141 }
142
143 @Override
144 protected void processFiltered(File file, FileText fileText) {
145 if (getHeaderLines().size() > fileText.size()) {
146 log(1, MSG_MISSING);
147 }
148 else {
149 for (int i = 0; i < getHeaderLines().size(); i++) {
150 if (!isMatch(i, fileText.get(i))) {
151 log(i + 1, MSG_MISMATCH, getHeaderLines().get(i));
152 break;
153 }
154 }
155 }
156 }
157
158 @Override
159 protected void postProcessHeaderLines() {
160 // no code
161 }
162
163 }