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.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 * <p>
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 * </p>
36 * <p>
37 * Property {@code ignoreLines} specifies the line numbers to ignore when matching
38 * lines in a header file. This property is very useful for supporting headers
39 * that contain copyright dates. For example, consider the following header:
40 * </p>
41 * <pre>
42 * line 1: ////////////////////////////////////////////////////////////////////
43 * line 2: // checkstyle:
44 * line 3: // Checks Java source code for adherence to a set of rules.
45 * line 4: // Copyright (C) 2002 Oliver Burn
46 * line 5: ////////////////////////////////////////////////////////////////////
47 * </pre>
48 * <p>
49 * Since the year information will change over time, you can tell Checkstyle
50 * to ignore line 4 by setting property {@code ignoreLines} to {@code 4}.
51 * </p>
52 * <p>
53 * In default configuration, if header is not specified, the default value
54 * of header is set to {@code null} and the check does not rise any violations.
55 * </p>
56 * <ul>
57 * <li>
58 * Property {@code charset} - Specify the character encoding to use when reading the headerFile.
59 * Type is {@code java.lang.String}.
60 * Default value is {@code the charset property of the parent
61 * <a href="https://checkstyle.org/config.html#Checker">Checker</a> module}.
62 * </li>
63 * <li>
64 * Property {@code fileExtensions} - Specify the file extensions of the files to process.
65 * Type is {@code java.lang.String[]}.
66 * Default value is {@code ""}.
67 * </li>
68 * <li>
69 * Property {@code header} - Specify the required header specified inline.
70 * Individual header lines must be separated by the string {@code "\n"}
71 * (even on platforms with a different line separator).
72 * Type is {@code java.lang.String}.
73 * Default value is {@code null}.
74 * </li>
75 * <li>
76 * Property {@code headerFile} - Specify the name of the file containing the required header.
77 * Type is {@code java.net.URI}.
78 * Default value is {@code null}.
79 * </li>
80 * <li>
81 * Property {@code ignoreLines} - Specify the line numbers to ignore.
82 * Type is {@code int[]}.
83 * Default value is {@code ""}.
84 * </li>
85 * </ul>
86 * <p>
87 * Parent is {@code com.puppycrawl.tools.checkstyle.Checker}
88 * </p>
89 * <p>
90 * Violation Message Keys:
91 * </p>
92 * <ul>
93 * <li>
94 * {@code header.mismatch}
95 * </li>
96 * <li>
97 * {@code header.missing}
98 * </li>
99 * </ul>
100 *
101 * @since 6.9
102 */
103 @StatelessCheck
104 public class HeaderCheck extends AbstractHeaderCheck {
105
106 /**
107 * A key is pointing to the warning message text in "messages.properties"
108 * file.
109 */
110 public static final String MSG_MISSING = "header.missing";
111
112 /**
113 * A key is pointing to the warning message text in "messages.properties"
114 * file.
115 */
116 public static final String MSG_MISMATCH = "header.mismatch";
117
118 /** Specify the line numbers to ignore. */
119 private BitSet ignoreLines = new BitSet();
120
121 /**
122 * Returns true if lineNo is header lines or false.
123 *
124 * @param lineNo a line number
125 * @return if {@code lineNo} is one of the ignored header lines.
126 */
127 private boolean isIgnoreLine(int lineNo) {
128 return ignoreLines.get(lineNo);
129 }
130
131 /**
132 * Checks if a code line matches the required header line.
133 *
134 * @param lineNumber the line number to check against the header
135 * @param line the line contents
136 * @return true if and only if the line matches the required header line
137 */
138 private boolean isMatch(int lineNumber, String line) {
139 // skip lines we are meant to ignore
140 return isIgnoreLine(lineNumber + 1)
141 || getHeaderLines().get(lineNumber).equals(line);
142 }
143
144 /**
145 * Setter to specify the line numbers to ignore.
146 *
147 * @param lines line numbers to ignore in header.
148 * @since 3.2
149 */
150 public void setIgnoreLines(int... lines) {
151 ignoreLines = TokenUtil.asBitSet(lines);
152 }
153
154 @Override
155 protected void processFiltered(File file, FileText fileText) {
156 if (getHeaderLines().size() > fileText.size()) {
157 log(1, MSG_MISSING);
158 }
159 else {
160 for (int i = 0; i < getHeaderLines().size(); i++) {
161 if (!isMatch(i, fileText.get(i))) {
162 log(i + 1, MSG_MISMATCH, getHeaderLines().get(i));
163 break;
164 }
165 }
166 }
167 }
168
169 @Override
170 protected void postProcessHeaderLines() {
171 // no code
172 }
173
174 }