001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2014  Oliver Burn
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////////////////////////////////////////////////////////////////////////////////
019package com.puppycrawl.tools.checkstyle.checks.coding;
020
021import com.puppycrawl.tools.checkstyle.api.Check;
022import com.puppycrawl.tools.checkstyle.api.DetailAST;
023import com.puppycrawl.tools.checkstyle.api.TokenTypes;
024
025/**
026 * <p>
027 * Check that the <code>default</code> is after all the <code>case</code>s
028 * in a <code>switch</code> statement.
029 * </p>
030 * <p>
031 * Rationale: Java allows <code>default</code> anywhere within the
032 * <code>switch</code> statement. But if it comes after the last
033 * <code>case</code> then it is more readable.
034 * </p>
035 * <p>
036 * An example of how to configure the check is:
037 * </p>
038 * <pre>
039 * &lt;module name="DefaultComesLast"/&gt;
040 * </pre>
041 * @author o_sukhodolsky
042 */
043public class DefaultComesLastCheck extends Check
044{
045    /** Creates new instance of the check. */
046    public DefaultComesLastCheck()
047    {
048        // do nothing
049    }
050
051    @Override
052    public int[] getDefaultTokens()
053    {
054        return new int[] {
055            TokenTypes.LITERAL_DEFAULT,
056        };
057    }
058
059    @Override
060    public int[] getAcceptableTokens()
061    {
062        return getDefaultTokens();
063    }
064
065    @Override
066    public void visitToken(DetailAST ast)
067    {
068        final DetailAST defaultGroupAST = ast.getParent();
069        //default keywords used in annotations too - not what we're
070        //interested in
071        if (defaultGroupAST.getType() != TokenTypes.ANNOTATION_FIELD_DEF
072                && defaultGroupAST.getType() != TokenTypes.MODIFIERS)
073        {
074            final DetailAST switchAST = defaultGroupAST.getParent();
075            final DetailAST lastGroupAST =
076                switchAST.getLastChild().getPreviousSibling();
077
078            if ((defaultGroupAST.getLineNo() != lastGroupAST.getLineNo())
079                || (defaultGroupAST.getColumnNo()
080                    != lastGroupAST.getColumnNo()))
081            {
082                log(ast, "default.comes.last");
083            }
084        }
085    }
086}