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.javadoc;
21
22 import java.util.Arrays;
23 import java.util.regex.Pattern;
24
25 import com.puppycrawl.tools.checkstyle.StatelessCheck;
26 import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
27 import com.puppycrawl.tools.checkstyle.api.DetailAST;
28 import com.puppycrawl.tools.checkstyle.api.FileContents;
29 import com.puppycrawl.tools.checkstyle.api.TextBlock;
30 import com.puppycrawl.tools.checkstyle.api.TokenTypes;
31 import com.puppycrawl.tools.checkstyle.checks.naming.AccessModifierOption;
32 import com.puppycrawl.tools.checkstyle.utils.CheckUtil;
33 import com.puppycrawl.tools.checkstyle.utils.ScopeUtil;
34 import com.puppycrawl.tools.checkstyle.utils.UnmodifiableCollectionUtil;
35
36 /**
37 * <div>
38 * Checks that a variable has a Javadoc comment. Ignores {@code serialVersionUID} fields.
39 * </div>
40 * <ul>
41 * <li>
42 * Property {@code accessModifiers} - Specify the set of access modifiers used to determine which
43 * fields should be checked. This includes both explicitly declared modifiers and implicit ones,
44 * such as package-private for fields without an explicit modifier.
45 * It also accounts for special cases where fields have implicit modifiers,
46 * such as {@code public static final} for interface fields and {@code public static}
47 * for enum constants, or where the nesting types accessibility is more restrictive and hides the
48 * nested field. Only fields matching the specified modifiers will be analyzed.
49 * Type is {@code com.puppycrawl.tools.checkstyle.checks.naming.AccessModifierOption[]}.
50 * Default value is {@code public, protected, package, private}.
51 * </li>
52 * <li>
53 * Property {@code ignoreNamePattern} - Specify the regexp to define variable names to ignore.
54 * Type is {@code java.util.regex.Pattern}.
55 * Default value is {@code null}.
56 * </li>
57 * <li>
58 * Property {@code tokens} - tokens to check
59 * Type is {@code java.lang.String[]}.
60 * Validation type is {@code tokenSet}.
61 * Default value is:
62 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#ENUM_CONSTANT_DEF">
63 * ENUM_CONSTANT_DEF</a>.
64 * </li>
65 * </ul>
66 *
67 * <p>
68 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
69 * </p>
70 *
71 * <p>
72 * Violation Message Keys:
73 * </p>
74 * <ul>
75 * <li>
76 * {@code javadoc.missing}
77 * </li>
78 * </ul>
79 *
80 * @since 3.0
81 */
82 @StatelessCheck
83 public class JavadocVariableCheck
84 extends AbstractCheck {
85
86 /**
87 * A key is pointing to the warning message text in "messages.properties"
88 * file.
89 */
90
91 public static final String MSG_JAVADOC_MISSING = "javadoc.missing";
92 /**
93 * Specify the set of access modifiers used to determine which fields should be checked.
94 * This includes both explicitly declared modifiers and implicit ones, such as package-private
95 * for fields without an explicit modifier. It also accounts for special cases where fields
96 * have implicit modifiers, such as {@code public static final} for interface fields and
97 * {@code public static} for enum constants, or where the nesting types accessibility is more
98 * restrictive and hides the nested field.
99 * Only fields matching the specified modifiers will be analyzed.
100 */
101 private AccessModifierOption[] accessModifiers = {
102 AccessModifierOption.PUBLIC,
103 AccessModifierOption.PROTECTED,
104 AccessModifierOption.PACKAGE,
105 AccessModifierOption.PRIVATE,
106 };
107
108 /** Specify the regexp to define variable names to ignore. */
109 private Pattern ignoreNamePattern;
110
111 /**
112 * Setter to specify the set of access modifiers used to determine which fields should be
113 * checked. This includes both explicitly declared modifiers and implicit ones, such as
114 * package-private for fields without an explicit modifier. It also accounts for special
115 * cases where fields have implicit modifiers, such as {@code public static final}
116 * for interface fields and {@code public static} for enum constants, or where the nesting
117 * types accessibility is more restrictive and hides the nested field.
118 * Only fields matching the specified modifiers will be analyzed.
119 *
120 * @param accessModifiers access modifiers of fields to check.
121 * @since 10.22.0
122 */
123 public void setAccessModifiers(AccessModifierOption... accessModifiers) {
124 this.accessModifiers =
125 UnmodifiableCollectionUtil.copyOfArray(accessModifiers, accessModifiers.length);
126 }
127
128 /**
129 * Setter to specify the regexp to define variable names to ignore.
130 *
131 * @param pattern a pattern.
132 * @since 5.8
133 */
134 public void setIgnoreNamePattern(Pattern pattern) {
135 ignoreNamePattern = pattern;
136 }
137
138 @Override
139 public int[] getDefaultTokens() {
140 return getAcceptableTokens();
141 }
142
143 @Override
144 public int[] getAcceptableTokens() {
145 return new int[] {
146 TokenTypes.VARIABLE_DEF,
147 TokenTypes.ENUM_CONSTANT_DEF,
148 };
149 }
150
151 /*
152 * Skipping enum values is requested.
153 * Checkstyle's issue #1669: https://github.com/checkstyle/checkstyle/issues/1669
154 */
155 @Override
156 public int[] getRequiredTokens() {
157 return new int[] {
158 TokenTypes.VARIABLE_DEF,
159 };
160 }
161
162 // suppress deprecation until https://github.com/checkstyle/checkstyle/issues/11166
163 @SuppressWarnings("deprecation")
164 @Override
165 public void visitToken(DetailAST ast) {
166 if (shouldCheck(ast)) {
167 final FileContents contents = getFileContents();
168 final TextBlock textBlock =
169 contents.getJavadocBefore(ast.getLineNo());
170
171 if (textBlock == null) {
172 log(ast, MSG_JAVADOC_MISSING);
173 }
174 }
175 }
176
177 /**
178 * Decides whether the variable name of an AST is in the ignore list.
179 *
180 * @param ast the AST to check
181 * @return true if the variable name of ast is in the ignore list.
182 */
183 private boolean isIgnored(DetailAST ast) {
184 final String name = ast.findFirstToken(TokenTypes.IDENT).getText();
185 return ignoreNamePattern != null && ignoreNamePattern.matcher(name).matches()
186 || "serialVersionUID".equals(name);
187 }
188
189 /**
190 * Checks whether a method has the correct access modifier to be checked.
191 *
192 * @param accessModifier the access modifier of the method.
193 * @return whether the method matches the expected access modifier.
194 */
195 private boolean matchAccessModifiers(AccessModifierOption accessModifier) {
196 return Arrays.stream(accessModifiers)
197 .anyMatch(modifier -> modifier == accessModifier);
198 }
199
200 /**
201 * Whether we should check this node.
202 *
203 * @param ast a given node.
204 * @return whether we should check a given node.
205 */
206 private boolean shouldCheck(final DetailAST ast) {
207 boolean result = false;
208 if (!ScopeUtil.isInCodeBlock(ast) && !isIgnored(ast)) {
209 final AccessModifierOption accessModifier =
210 getAccessModifierFromModifiersTokenWithPrivateEnumSupport(ast);
211 result = matchAccessModifiers(accessModifier);
212 }
213 return result;
214 }
215
216 /**
217 * A derivative of {@link CheckUtil#getAccessModifierFromModifiersToken(DetailAST)} that
218 * considers enum definitions' visibility when evaluating the accessibility of an enum
219 * constant.
220 * <br>
221 * <a href="https://github.com/checkstyle/checkstyle/pull/16787/files#r2073671898">Implemented
222 * separately</a> to reduce scope of fix for
223 * <a href="https://github.com/checkstyle/checkstyle/issues/16786">issue #16786</a> until a
224 * wider solution can be developed.
225 *
226 * @param ast the token of the method/constructor.
227 * @return the access modifier of the method/constructor.
228 */
229 public static AccessModifierOption getAccessModifierFromModifiersTokenWithPrivateEnumSupport(
230 DetailAST ast) {
231 // In some scenarios we want to investigate a parent AST instead
232 DetailAST selectedAst = ast;
233
234 if (selectedAst.getType() == TokenTypes.ENUM_CONSTANT_DEF) {
235 // Enum constants don't have modifiers
236 // implicitly public but validate against parent(s)
237 while (selectedAst.getType() != TokenTypes.ENUM_DEF) {
238 selectedAst = selectedAst.getParent();
239 }
240 }
241
242 return CheckUtil.getAccessModifierFromModifiersToken(selectedAst);
243 }
244 }