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 * Notes:
39 * In default configuration, if header is not specified, the default value
40 * of header is set to {@code null} and the check does not rise any violations.
41 * </p>
42 * <ul>
43 * <li>
44 * Property {@code charset} - Specify the character encoding to use when reading the headerFile.
45 * Type is {@code java.lang.String}.
46 * Default value is {@code the charset property of the parent
47 * <a href="https://checkstyle.org/config.html#Checker">Checker</a> module}.
48 * </li>
49 * <li>
50 * Property {@code fileExtensions} - Specify the file extensions of the files to process.
51 * Type is {@code java.lang.String[]}.
52 * Default value is {@code ""}.
53 * </li>
54 * <li>
55 * Property {@code header} - Specify the required header specified inline.
56 * Individual header lines must be separated by the string {@code "\n"}
57 * (even on platforms with a different line separator).
58 * Type is {@code java.lang.String}.
59 * Default value is {@code null}.
60 * </li>
61 * <li>
62 * Property {@code headerFile} - Specify the name of the file containing the required header.
63 * Type is {@code java.net.URI}.
64 * Default value is {@code null}.
65 * </li>
66 * <li>
67 * Property {@code ignoreLines} - Specifies the line
68 * numbers to ignore when matching lines in a content of headerFile.
69 * Type is {@code int[]}.
70 * Default value is {@code ""}.
71 * </li>
72 * </ul>
73 *
74 * <p>
75 * Parent is {@code com.puppycrawl.tools.checkstyle.Checker}
76 * </p>
77 *
78 * <p>
79 * Violation Message Keys:
80 * </p>
81 * <ul>
82 * <li>
83 * {@code header.mismatch}
84 * </li>
85 * <li>
86 * {@code header.missing}
87 * </li>
88 * </ul>
89 *
90 * @since 3.2
91 */
92 @StatelessCheck
93 public class HeaderCheck extends AbstractHeaderCheck {
94
95 /**
96 * A key is pointing to the warning message text in "messages.properties"
97 * file.
98 */
99 public static final String MSG_MISSING = "header.missing";
100
101 /**
102 * A key is pointing to the warning message text in "messages.properties"
103 * file.
104 */
105 public static final String MSG_MISMATCH = "header.mismatch";
106
107 /** Specifies the line numbers to ignore when matching lines in a content of headerFile. */
108 private BitSet ignoreLines = new BitSet();
109
110 /**
111 * Returns true if lineNo is header lines or false.
112 *
113 * @param lineNo a line number
114 * @return if {@code lineNo} is one of the ignored header lines.
115 */
116 private boolean isIgnoreLine(int lineNo) {
117 return ignoreLines.get(lineNo);
118 }
119
120 /**
121 * Checks if a code line matches the required header line.
122 *
123 * @param lineNumber the line number to check against the header
124 * @param line the line contents
125 * @return true if and only if the line matches the required header line
126 */
127 private boolean isMatch(int lineNumber, String line) {
128 // skip lines we are meant to ignore
129 return isIgnoreLine(lineNumber + 1)
130 || getHeaderLines().get(lineNumber).equals(line);
131 }
132
133 /**
134 * Setter to specifies the line numbers
135 * to ignore when matching lines in a content of headerFile.
136 *
137 * @param lines line numbers to ignore in header.
138 * @since 3.2
139 */
140 public void setIgnoreLines(int... lines) {
141 ignoreLines = TokenUtil.asBitSet(lines);
142 }
143
144 @Override
145 protected void processFiltered(File file, FileText fileText) {
146 if (getHeaderLines().size() > fileText.size()) {
147 log(1, MSG_MISSING);
148 }
149 else {
150 for (int i = 0; i < getHeaderLines().size(); i++) {
151 if (!isMatch(i, fileText.get(i))) {
152 log(i + 1, MSG_MISMATCH, getHeaderLines().get(i));
153 break;
154 }
155 }
156 }
157 }
158
159 @Override
160 protected void postProcessHeaderLines() {
161 // no code
162 }
163
164 }