001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2019 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;
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;
026
027/**
028 * Checks the style of array type definitions.
029 * Some like Java-style: {@code public static void main(String[] args)}
030 * and some like C-style: {@code public static void main(String args[])}.
031 *
032 * <p>By default the Check enforces Java style.</p>
033 *
034 * <p>This check strictly enforces only Java style for method return types
035 * regardless of the value for 'javaStyle'. For example, {@code byte[] getData()}.
036 * This is because C doesn't compile methods with array declarations on the name.</p>
037 */
038@StatelessCheck
039public class ArrayTypeStyleCheck extends AbstractCheck {
040
041    /**
042     * A key is pointing to the warning message text in "messages.properties"
043     * file.
044     */
045    public static final String MSG_KEY = "array.type.style";
046
047    /** Controls whether to use Java or C style. */
048    private boolean javaStyle = true;
049
050    @Override
051    public int[] getDefaultTokens() {
052        return getRequiredTokens();
053    }
054
055    @Override
056    public int[] getAcceptableTokens() {
057        return getRequiredTokens();
058    }
059
060    @Override
061    public int[] getRequiredTokens() {
062        return new int[] {TokenTypes.ARRAY_DECLARATOR};
063    }
064
065    @Override
066    public void visitToken(DetailAST ast) {
067        final DetailAST typeAST = ast.getParent();
068        if (typeAST.getType() == TokenTypes.TYPE) {
069            final DetailAST variableAST = typeAST.getNextSibling();
070            if (variableAST != null) {
071                final boolean isMethod = typeAST.getParent().getType() == TokenTypes.METHOD_DEF;
072                final boolean isJavaStyle = variableAST.getLineNo() > ast.getLineNo()
073                    || variableAST.getColumnNo() - ast.getColumnNo() > -1;
074
075                // force all methods to be Java style (see note in top Javadoc)
076                final boolean isMethodViolation = isMethod && !isJavaStyle;
077                final boolean isVariableViolation = !isMethod && isJavaStyle != javaStyle;
078
079                if (isMethodViolation || isVariableViolation) {
080                    log(ast, MSG_KEY);
081                }
082            }
083        }
084    }
085
086    /**
087     * Controls whether to check for Java or C style.
088     * @param javaStyle true if Java style should be used.
089     */
090    public void setJavaStyle(boolean javaStyle) {
091        this.javaStyle = javaStyle;
092    }
093
094}