001///////////////////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
003// Copyright (C) 2001-2026 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.annotation;
021
022import java.util.HashSet;
023import java.util.Set;
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.utils.AnnotationUtil;
030import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
031
032/**
033 * <div>
034 * Verifies that explicitly declared record accessor methods include
035 * the {@code @Override} annotation.
036 * </div>
037 *
038 * <p>
039 * Per <a href="https://openjdk.org/jeps/395">JEP 395</a>, the meaning of the
040 * {@code @Override} annotation was extended to include explicitly declared
041 * accessor methods for record components.
042 * </p>
043 *
044 * <p>
045 * This check focuses only on record component accessor methods. It does not
046 * attempt to detect general method overrides from interfaces or superclasses,
047 * due to Checkstyle's single-file analysis limitations.
048 * </p>
049 *
050 * @since 13.1.0
051 */
052@StatelessCheck
053public class MissingOverrideOnRecordAccessorCheck extends AbstractCheck {
054
055    /**
056     * A key is pointing to the warning message text in "messages.properties" file.
057     */
058    public static final String MSG_KEY = "annotation.missing.override.record.accessor";
059
060    /**
061     * Creates a new {@code MissingOverrideOnRecordAccessorCheck} instance.
062     */
063    public MissingOverrideOnRecordAccessorCheck() {
064        // no code by default
065    }
066
067    @Override
068    public int[] getDefaultTokens() {
069        return getRequiredTokens();
070    }
071
072    @Override
073    public int[] getAcceptableTokens() {
074        return getRequiredTokens();
075    }
076
077    @Override
078    public int[] getRequiredTokens() {
079        return new int[] {TokenTypes.METHOD_DEF};
080    }
081
082    @Override
083    public void visitToken(DetailAST ast) {
084        if (isRecordAccessorMethod(ast) && !AnnotationUtil.hasOverrideAnnotation(ast)) {
085            log(ast, MSG_KEY);
086        }
087    }
088
089    /**
090     * Checks if the given method is an explicitly declared accessor for a record component.
091     *
092     * @param ast the METHOD_DEF AST node
093     * @return true if this method is a record accessor
094     */
095    private static boolean isRecordAccessorMethod(DetailAST ast) {
096        boolean result = false;
097        final DetailAST grandParent = ast.getParent().getParent();
098        if (grandParent != null && grandParent.getType() == TokenTypes.RECORD_DEF) {
099            final DetailAST parameters = ast.findFirstToken(TokenTypes.PARAMETERS);
100            if (parameters.getChildCount() == 0) {
101                final String methodName = getMethodName(ast);
102                result = getRecordComponentNames(grandParent).contains(methodName);
103            }
104        }
105        return result;
106    }
107
108    /**
109     * Gets the method name from a method definition AST.
110     *
111     * @param methodDef the METHOD_DEF AST node
112     * @return the method name
113     */
114    private static String getMethodName(DetailAST methodDef) {
115        return TokenUtil.getIdent(methodDef).getText();
116    }
117
118    /**
119     * Gets the set of record component names from a record definition.
120     *
121     * @param recordDef the RECORD_DEF AST node
122     * @return set of component names
123     */
124    private static Set<String> getRecordComponentNames(DetailAST recordDef) {
125        final Set<String> names = new HashSet<>();
126        final DetailAST recordComponents = recordDef.findFirstToken(TokenTypes.RECORD_COMPONENTS);
127        DetailAST child = recordComponents.getFirstChild();
128        while (child != null) {
129            if (child.getType() == TokenTypes.RECORD_COMPONENT_DEF) {
130                names.add(TokenUtil.getIdent(child).getText());
131            }
132            child = child.getNextSibling();
133        }
134        return names;
135    }
136
137}