001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2017 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.naming;
021
022import com.puppycrawl.tools.checkstyle.api.DetailAST;
023import com.puppycrawl.tools.checkstyle.api.TokenTypes;
024
025/**
026 * <p>
027 * Checks that interface type parameter names conform to a format specified
028 * by the format property.  The format is a
029 * {@link java.util.regex.Pattern regular expression} and defaults to
030 * <strong>^[A-Z]$</strong>.
031 * </p>
032 * <p>
033 * An example of how to configure the check is:
034 * </p>
035 * <pre>
036 * &lt;module name="InterfaceTypeParameterName"/&gt;
037 * </pre>
038 * <p>
039 * An example of how to configure the check for names that are only a single
040 * letter is
041 * </p>
042 * <pre>
043 * &lt;module name="InterfaceTypeParameterName"&gt;
044 *    &lt;property name="format" value="^[a-zA-Z]$"/&gt;
045 * &lt;/module&gt;
046 * </pre>
047 *
048 * @author maxvetrenko
049 */
050public class InterfaceTypeParameterNameCheck
051    extends AbstractNameCheck {
052    /** Creates a new {@code InterfaceTypeParameterNameCheck} instance. */
053    public InterfaceTypeParameterNameCheck() {
054        super("^[A-Z]$");
055    }
056
057    @Override
058    public int[] getDefaultTokens() {
059        return getAcceptableTokens();
060    }
061
062    @Override
063    public int[] getAcceptableTokens() {
064        return new int[] {
065            TokenTypes.TYPE_PARAMETER,
066        };
067    }
068
069    @Override
070    public int[] getRequiredTokens() {
071        return getAcceptableTokens();
072    }
073
074    @Override
075    protected final boolean mustCheckName(DetailAST ast) {
076        final DetailAST location =
077            ast.getParent().getParent();
078        return location.getType() == TokenTypes.INTERFACE_DEF;
079    }
080}