001///////////////////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
003// Copyright (C) 2001-2025 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.DetailNode;
024import com.puppycrawl.tools.checkstyle.api.JavadocTokenTypes;
025import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
026import com.puppycrawl.tools.checkstyle.utils.JavadocUtil;
027
028/**
029 * <div>
030 * Checks that the block tag is followed by description.
031 * </div>
032 *
033 * @since 6.0
034 */
035@StatelessCheck
036public class NonEmptyAtclauseDescriptionCheck extends AbstractJavadocCheck {
037
038    /**
039     * A key is pointing to the warning message text in "messages.properties"
040     * file.
041     */
042    public static final String MSG_KEY = "non.empty.atclause";
043
044    @Override
045    public int[] getDefaultJavadocTokens() {
046        return new int[] {
047            JavadocTokenTypes.PARAM_LITERAL,
048            JavadocTokenTypes.RETURN_LITERAL,
049            JavadocTokenTypes.THROWS_LITERAL,
050            JavadocTokenTypes.EXCEPTION_LITERAL,
051            JavadocTokenTypes.DEPRECATED_LITERAL,
052        };
053    }
054
055    /**
056     * Adds a set of tokens the check is interested in.
057     *
058     * @param strRep the string representation of the tokens interested in
059     * @propertySince 7.3
060     * @noinspection RedundantMethodOverride
061     * @noinspectionreason Display module's unique property version
062     */
063    @Override
064    public void setJavadocTokens(String... strRep) {
065        super.setJavadocTokens(strRep);
066    }
067
068    @Override
069    public void visitJavadocToken(DetailNode ast) {
070        if (isEmptyTag(ast.getParent())) {
071            log(ast.getLineNumber(), MSG_KEY);
072        }
073    }
074
075    /**
076     * Tests if block tag is empty.
077     *
078     * @param tagNode block tag.
079     * @return true, if block tag is empty.
080     */
081    private static boolean isEmptyTag(DetailNode tagNode) {
082        final DetailNode tagDescription =
083                JavadocUtil.findFirstToken(tagNode, JavadocTokenTypes.DESCRIPTION);
084        return tagDescription == null
085            || hasOnlyEmptyText(tagDescription);
086    }
087
088    /**
089     * Tests if description node is empty (has only new lines and blank strings).
090     *
091     * @param description description node.
092     * @return true, if description node has only new lines and blank strings.
093     */
094    private static boolean hasOnlyEmptyText(DetailNode description) {
095        boolean result = true;
096        for (DetailNode child : description.getChildren()) {
097            if (child.getType() != JavadocTokenTypes.LEADING_ASTERISK
098                    && !CommonUtil.isBlank(child.getText())) {
099                result = false;
100                break;
101            }
102        }
103        return result;
104    }
105
106}