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.annotation;
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.AnnotationUtil;
027
028/**
029 * <p>
030 * Checks that all package annotations are in the package-info.java file.
031 * </p>
032 * <p>
033 * According to the Java Language Specification.
034 * </p>
035 * <p>
036 * The JLS does not enforce the placement of package annotations.
037 * This placement may vary based on implementation. The JLS
038 * does highly recommend that all package annotations are
039 * placed in the package-info.java file.
040 *
041 * See <a
042 * href="https://docs.oracle.com/javase/specs/jls/se11/html/jls-7.html#jls-7.4.1">
043 * Java Language Specification, &#167;7.4.1</a>.
044 * </p>
045 * <p>
046 * To configure the check:
047 * </p>
048 * <pre>
049 * &lt;module name=&quot;PackageAnnotation&quot;/&gt;
050 * </pre>
051 *
052 * @since 5.0
053 */
054@StatelessCheck
055public class PackageAnnotationCheck extends AbstractCheck {
056
057    /**
058     * A key is pointing to the warning message text in "messages.properties"
059     * file.
060     */
061    public static final String MSG_KEY = "annotation.package.location";
062
063    @Override
064    public int[] getDefaultTokens() {
065        return getRequiredTokens();
066    }
067
068    @Override
069    public int[] getRequiredTokens() {
070        return new int[] {
071            TokenTypes.PACKAGE_DEF,
072        };
073    }
074
075    @Override
076    public int[] getAcceptableTokens() {
077        return getRequiredTokens();
078    }
079
080    @Override
081    public void visitToken(final DetailAST ast) {
082        final boolean containsAnnotation =
083            AnnotationUtil.containsAnnotation(ast);
084        final boolean inPackageInfo =
085            getFileContents().inPackageInfo();
086
087        if (containsAnnotation && !inPackageInfo) {
088            log(ast.getLineNo(), MSG_KEY);
089        }
090    }
091
092}