001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2020 the original author or authors.
004//
005// This library is free software; you can redistribute it and/or
006// modify it under the terms of the GNU Lesser General Public
007// License as published by the Free Software Foundation; either
008// version 2.1 of the License, or (at your option) any later version.
009//
010// This library is distributed in the hope that it will be useful,
011// but WITHOUT ANY WARRANTY; without even the implied warranty of
012// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
013// Lesser General Public License for more details.
014//
015// You should have received a copy of the GNU Lesser General Public
016// License along with this library; if not, write to the Free Software
017// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
018////////////////////////////////////////////////////////////////////////////////
019
020package com.puppycrawl.tools.checkstyle.checks.javadoc;
021
022import java.util.regex.Pattern;
023
024import com.puppycrawl.tools.checkstyle.StatelessCheck;
025import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
026import com.puppycrawl.tools.checkstyle.api.DetailAST;
027import com.puppycrawl.tools.checkstyle.api.FileContents;
028import com.puppycrawl.tools.checkstyle.api.Scope;
029import com.puppycrawl.tools.checkstyle.api.TextBlock;
030import com.puppycrawl.tools.checkstyle.api.TokenTypes;
031import com.puppycrawl.tools.checkstyle.utils.ScopeUtil;
032
033/**
034 * <p>
035 * Checks that a variable has a Javadoc comment. Ignores {@code serialVersionUID} fields.
036 * </p>
037 * <ul>
038 * <li>
039 * Property {@code scope} - Specify the visibility scope where Javadoc comments are checked.
040 * Default value is {@code private}.
041 * </li>
042 * <li>
043 * Property {@code excludeScope} - Specify the visibility scope where Javadoc
044 * comments are not checked.
045 * Default value is {@code null}.
046 * </li>
047 * <li>
048 * Property {@code ignoreNamePattern} - Specify the regexp to define variable names to ignore.
049 * Default value is {@code null}.
050 * </li>
051 * <li>
052 * Property {@code tokens} - tokens to check Default value is:
053 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#ENUM_CONSTANT_DEF">
054 * ENUM_CONSTANT_DEF</a>.
055 * </li>
056 * </ul>
057 * <p>
058 * To configure the default check:
059 * </p>
060 * <pre>
061 * &lt;module name="JavadocVariable"/&gt;
062 * </pre>
063 * <p>
064 * To configure the check for {@code public} scope:
065 * </p>
066 * <pre>
067 * &lt;module name="JavadocVariable"&gt;
068 *   &lt;property name="scope" value="public"/&gt;
069 * &lt;/module&gt;
070 * </pre>
071 * <p>
072 * To configure the check for members which are in {@code private},
073 * but not in {@code protected} scope:
074 * </p>
075 * <pre>
076 * &lt;module name="JavadocVariable"&gt;
077 *   &lt;property name="scope" value="private"/&gt;
078 *   &lt;property name="excludeScope" value="protected"/&gt;
079 * &lt;/module&gt;
080 * </pre>
081 * <p>
082 * To ignore absence of Javadoc comments for variables with names {@code log} or {@code logger}:
083 * </p>
084 * <pre>
085 * &lt;module name="JavadocVariable"&gt;
086 *   &lt;property name="ignoreNamePattern" value="log|logger"/&gt;
087 * &lt;/module&gt;
088 * </pre>
089 *
090 * @since 3.0
091 */
092@StatelessCheck
093public class JavadocVariableCheck
094    extends AbstractCheck {
095
096    /**
097     * A key is pointing to the warning message text in "messages.properties"
098     * file.
099     */
100    public static final String MSG_JAVADOC_MISSING = "javadoc.missing";
101
102    /** Specify the visibility scope where Javadoc comments are checked. */
103    private Scope scope = Scope.PRIVATE;
104
105    /** Specify the visibility scope where Javadoc comments are not checked. */
106    private Scope excludeScope;
107
108    /** Specify the regexp to define variable names to ignore. */
109    private Pattern ignoreNamePattern;
110
111    /**
112     * Setter to specify the visibility scope where Javadoc comments are checked.
113     *
114     * @param scope a scope.
115     */
116    public void setScope(Scope scope) {
117        this.scope = scope;
118    }
119
120    /**
121     * Setter to specify the visibility scope where Javadoc comments are not checked.
122     *
123     * @param excludeScope a scope.
124     */
125    public void setExcludeScope(Scope excludeScope) {
126        this.excludeScope = excludeScope;
127    }
128
129    /**
130     * Setter to specify the regexp to define variable names to ignore.
131     *
132     * @param pattern a pattern.
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    @Override
163    public void visitToken(DetailAST ast) {
164        if (shouldCheck(ast)) {
165            final FileContents contents = getFileContents();
166            final TextBlock textBlock =
167                contents.getJavadocBefore(ast.getLineNo());
168
169            if (textBlock == null) {
170                log(ast, MSG_JAVADOC_MISSING);
171            }
172        }
173    }
174
175    /**
176     * Decides whether the variable name of an AST is in the ignore list.
177     * @param ast the AST to check
178     * @return true if the variable name of ast is in the ignore list.
179     */
180    private boolean isIgnored(DetailAST ast) {
181        final String name = ast.findFirstToken(TokenTypes.IDENT).getText();
182        return ignoreNamePattern != null && ignoreNamePattern.matcher(name).matches()
183            || "serialVersionUID".equals(name);
184    }
185
186    /**
187     * Whether we should check this node.
188     * @param ast a given node.
189     * @return whether we should check a given node.
190     */
191    private boolean shouldCheck(final DetailAST ast) {
192        boolean result = false;
193        if (!ScopeUtil.isInCodeBlock(ast) && !isIgnored(ast)) {
194            Scope customScope = Scope.PUBLIC;
195            if (ast.getType() != TokenTypes.ENUM_CONSTANT_DEF
196                    && !ScopeUtil.isInInterfaceOrAnnotationBlock(ast)) {
197                final DetailAST mods = ast.findFirstToken(TokenTypes.MODIFIERS);
198                customScope = ScopeUtil.getScopeFromMods(mods);
199            }
200
201            final Scope surroundingScope = ScopeUtil.getSurroundingScope(ast);
202            result = customScope.isIn(scope) && surroundingScope.isIn(scope)
203                && (excludeScope == null
204                    || !customScope.isIn(excludeScope)
205                    || !surroundingScope.isIn(excludeScope));
206        }
207        return result;
208    }
209
210}