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.javadoc;
021
022import com.puppycrawl.tools.checkstyle.StatelessCheck;
023import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
024import com.puppycrawl.tools.checkstyle.api.DetailAST;
025import com.puppycrawl.tools.checkstyle.api.TokenTypes;
026import com.puppycrawl.tools.checkstyle.utils.JavadocUtil;
027
028/**
029 * <div>
030 * Checks that Javadocs are located at the correct position. As specified at
031 * <a href="https://docs.oracle.com/en/java/javase/17/docs/specs/javadoc/doc-comment-spec.html">
032 * Documentation Comment Specification for the Standard Doclet</a>, Javadocs are recognized
033 * only when placed immediately before module, package, class, interface,
034 * constructor, method, or field declarations. Any other position, like in the
035 * body of a method, will be ignored by the javadoc tool and is considered invalid by this check.
036 * </div>
037 *
038 * @since 8.23
039 */
040@StatelessCheck
041public class InvalidJavadocPositionCheck extends AbstractCheck {
042
043    /**
044     * A key is pointing to the warning message text in "messages.properties" file.
045     */
046    public static final String MSG_KEY = "invalid.position";
047
048    /**
049     * Creates a new {@code InvalidJavadocPositionCheck} instance.
050     */
051    public InvalidJavadocPositionCheck() {
052        // no code by default
053    }
054
055    @Override
056    public int[] getDefaultTokens() {
057        return new int[] {
058            TokenTypes.BLOCK_COMMENT_BEGIN,
059        };
060    }
061
062    @Override
063    public int[] getAcceptableTokens() {
064        return getDefaultTokens();
065    }
066
067    @Override
068    public int[] getRequiredTokens() {
069        return getDefaultTokens();
070    }
071
072    @Override
073    public boolean isCommentNodesRequired() {
074        return true;
075    }
076
077    @Override
078    public void visitToken(DetailAST ast) {
079        final String commentContent = JavadocUtil.getBlockCommentContent(ast);
080
081        if (JavadocUtil.isJavadocComment(commentContent)
082                && !JavadocUtil.isCorrectJavadocPosition(ast)) {
083            log(ast, MSG_KEY);
084        }
085    }
086
087}