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;
21
22 import com.puppycrawl.tools.checkstyle.StatelessCheck;
23 import com.puppycrawl.tools.checkstyle.api.DetailNode;
24 import com.puppycrawl.tools.checkstyle.api.JavadocTokenTypes;
25 import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
26 import com.puppycrawl.tools.checkstyle.utils.JavadocUtil;
27
28 /**
29 * <p>
30 * Checks that the block tag is followed by description.
31 * </p>
32 * <ul>
33 * <li>
34 * Property {@code violateExecutionOnNonTightHtml} - Control when to print violations
35 * if the Javadoc being examined by this check violates the tight html rules defined at
36 * <a href="https://checkstyle.org/writingjavadocchecks.html#Tight-HTML_rules">Tight-HTML Rules</a>.
37 * Type is {@code boolean}.
38 * Default value is {@code false}.
39 * </li>
40 * <li>
41 * Property {@code javadocTokens} - javadoc tokens to check
42 * Type is {@code java.lang.String[]}.
43 * Validation type is {@code tokenSet}.
44 * Default value is
45 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/JavadocTokenTypes.html#PARAM_LITERAL">
46 * PARAM_LITERAL</a>,
47 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/JavadocTokenTypes.html#RETURN_LITERAL">
48 * RETURN_LITERAL</a>,
49 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/JavadocTokenTypes.html#THROWS_LITERAL">
50 * THROWS_LITERAL</a>,
51 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/JavadocTokenTypes.html#EXCEPTION_LITERAL">
52 * EXCEPTION_LITERAL</a>,
53 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/JavadocTokenTypes.html#DEPRECATED_LITERAL">
54 * DEPRECATED_LITERAL</a>.
55 * </li>
56 * </ul>
57 * <p>
58 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
59 * </p>
60 * <p>
61 * Violation Message Keys:
62 * </p>
63 * <ul>
64 * <li>
65 * {@code javadoc.missed.html.close}
66 * </li>
67 * <li>
68 * {@code javadoc.parse.rule.error}
69 * </li>
70 * <li>
71 * {@code javadoc.unclosedHtml}
72 * </li>
73 * <li>
74 * {@code javadoc.wrong.singleton.html.tag}
75 * </li>
76 * <li>
77 * {@code non.empty.atclause}
78 * </li>
79 * </ul>
80 *
81 * @since 6.0
82 */
83 @StatelessCheck
84 public class NonEmptyAtclauseDescriptionCheck extends AbstractJavadocCheck {
85
86 /**
87 * A key is pointing to the warning message text in "messages.properties"
88 * file.
89 */
90 public static final String MSG_KEY = "non.empty.atclause";
91
92 @Override
93 public int[] getDefaultJavadocTokens() {
94 return new int[] {
95 JavadocTokenTypes.PARAM_LITERAL,
96 JavadocTokenTypes.RETURN_LITERAL,
97 JavadocTokenTypes.THROWS_LITERAL,
98 JavadocTokenTypes.EXCEPTION_LITERAL,
99 JavadocTokenTypes.DEPRECATED_LITERAL,
100 };
101 }
102
103 @Override
104 public void visitJavadocToken(DetailNode ast) {
105 if (isEmptyTag(ast.getParent())) {
106 log(ast.getLineNumber(), MSG_KEY);
107 }
108 }
109
110 /**
111 * Tests if block tag is empty.
112 *
113 * @param tagNode block tag.
114 * @return true, if block tag is empty.
115 */
116 private static boolean isEmptyTag(DetailNode tagNode) {
117 final DetailNode tagDescription =
118 JavadocUtil.findFirstToken(tagNode, JavadocTokenTypes.DESCRIPTION);
119 return tagDescription == null
120 || hasOnlyEmptyText(tagDescription);
121 }
122
123 /**
124 * Tests if description node is empty (has only new lines and blank strings).
125 *
126 * @param description description node.
127 * @return true, if description node has only new lines and blank strings.
128 */
129 private static boolean hasOnlyEmptyText(DetailNode description) {
130 boolean result = true;
131 for (DetailNode child : description.getChildren()) {
132 if (child.getType() != JavadocTokenTypes.LEADING_ASTERISK
133 && !CommonUtil.isBlank(child.getText())) {
134 result = false;
135 break;
136 }
137 }
138 return result;
139 }
140
141 }