001///////////////////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
003// Copyright (C) 2001-2024 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.sizes;
021
022import java.util.Arrays;
023import java.util.concurrent.atomic.AtomicInteger;
024
025import com.puppycrawl.tools.checkstyle.StatelessCheck;
026import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
027import com.puppycrawl.tools.checkstyle.api.DetailAST;
028import com.puppycrawl.tools.checkstyle.api.TokenTypes;
029import com.puppycrawl.tools.checkstyle.checks.naming.AccessModifierOption;
030import com.puppycrawl.tools.checkstyle.utils.CheckUtil;
031import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
032
033/**
034 * <p>
035 * Checks the number of record components in the
036 * <a href="https://docs.oracle.com/javase/specs/jls/se14/preview/specs/records-jls.html#jls-8.10.1">
037 * header</a> of a record definition.
038 * </p>
039 * <ul>
040 * <li>
041 * Property {@code accessModifiers} - Access modifiers of record definitions where
042 * the number of record components should be checked.
043 * Type is {@code com.puppycrawl.tools.checkstyle.checks.naming.AccessModifierOption[]}.
044 * Default value is {@code public, protected, package, private}.
045 * </li>
046 * <li>
047 * Property {@code max} - Specify the maximum number of components allowed in the header of a
048 * record definition.
049 * Type is {@code int}.
050 * Default value is {@code 8}.
051 * </li>
052 * </ul>
053 * <p>
054 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
055 * </p>
056 * <p>
057 * Violation Message Keys:
058 * </p>
059 * <ul>
060 * <li>
061 * {@code too.many.components}
062 * </li>
063 * </ul>
064 *
065 * @since 8.36
066 */
067@StatelessCheck
068public class RecordComponentNumberCheck extends AbstractCheck {
069
070    /**
071     * A key is pointing to the warning message text in "messages.properties"
072     * file.
073     */
074    public static final String MSG_KEY = "too.many.components";
075
076    /** Default maximum number of allowed components. */
077    private static final int DEFAULT_MAX_COMPONENTS = 8;
078
079    /** Specify the maximum number of components allowed in the header of a record definition. */
080    private int max = DEFAULT_MAX_COMPONENTS;
081
082    /**
083     * Access modifiers of record definitions where the number
084     * of record components should be checked.
085     */
086    private AccessModifierOption[] accessModifiers = {
087        AccessModifierOption.PUBLIC,
088        AccessModifierOption.PROTECTED,
089        AccessModifierOption.PACKAGE,
090        AccessModifierOption.PRIVATE,
091    };
092
093    /**
094     * Setter to specify the maximum number of components allowed in the header
095     * of a record definition.
096     *
097     * @param value the maximum allowed.
098     * @since 8.36
099     */
100    public void setMax(int value) {
101        max = value;
102    }
103
104    /**
105     * Setter to access modifiers of record definitions where the number of record
106     * components should be checked.
107     *
108     * @param accessModifiers access modifiers of record definitions which should be checked.
109     * @since 8.36
110     */
111    public void setAccessModifiers(AccessModifierOption... accessModifiers) {
112        this.accessModifiers =
113                Arrays.copyOf(accessModifiers, accessModifiers.length);
114    }
115
116    @Override
117    public int[] getDefaultTokens() {
118        return getAcceptableTokens();
119    }
120
121    @Override
122    public int[] getAcceptableTokens() {
123        return new int[] {
124            TokenTypes.RECORD_DEF,
125        };
126    }
127
128    @Override
129    public int[] getRequiredTokens() {
130        return getAcceptableTokens();
131    }
132
133    @Override
134    public void visitToken(DetailAST ast) {
135        final AccessModifierOption accessModifier =
136            CheckUtil.getAccessModifierFromModifiersToken(ast);
137
138        if (matchAccessModifiers(accessModifier)) {
139            final DetailAST recordComponents =
140                ast.findFirstToken(TokenTypes.RECORD_COMPONENTS);
141            final int componentCount = countComponents(recordComponents);
142
143            if (componentCount > max) {
144                log(ast, MSG_KEY, componentCount, max);
145            }
146        }
147    }
148
149    /**
150     * Method to count the number of record components in this record definition.
151     *
152     * @param recordComponents the ast to check
153     * @return the number of record components in this record definition
154     */
155    private static int countComponents(DetailAST recordComponents) {
156        final AtomicInteger count = new AtomicInteger(0);
157        TokenUtil.forEachChild(recordComponents,
158            TokenTypes.RECORD_COMPONENT_DEF,
159            node -> count.getAndIncrement());
160        return count.get();
161    }
162
163    /**
164     * Checks whether a record definition has the correct access modifier to be checked.
165     *
166     * @param accessModifier the access modifier of the record definition.
167     * @return whether the record definition matches the expected access modifier.
168     */
169    private boolean matchAccessModifiers(final AccessModifierOption accessModifier) {
170        return Arrays.stream(accessModifiers)
171                .anyMatch(modifier -> modifier == accessModifier);
172    }
173}