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;
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>Checks that long constants are defined with an upper ell.
027 * That is <span class="code">'L'</span> and not
028 * <span class="code">'l'</span>. This is in accordance to the Java Language
029 * Specification, <a href=
030"http://java.sun.com/docs/books/jls/second_edition/html/lexical.doc.html#48282"
031 * >Section 3.10.1</a>.
032 * </p>
033 * <p>
034 * Rationale: The letter <span class="code">l</span> looks a lot
035 * like the number <span class="code">1</span>.
036 * </p>
037 *
038 * Examples
039 * <p class="body">
040 * To configure the check:
041 *
042 * </p>
043 * <pre class="body">
044 * &lt;module name=&quot;UpperEll&quot;/&gt;
045 * </pre>
046 *
047 * @author Oliver Burn
048 * @version 1.0
049 */
050public class UpperEllCheck extends Check
051{
052    @Override
053    public int[] getDefaultTokens()
054    {
055        return new int[] {TokenTypes.NUM_LONG};
056    }
057
058    @Override
059    public void visitToken(DetailAST ast)
060    {
061        if (ast.getText().endsWith("l")) {
062            log(ast.getLineNo(),
063                ast.getColumnNo() + ast.getText().length() - 1,
064                "upperEll");
065        }
066    }
067}