////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2012  Oliver Burn
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
////////////////////////////////////////////////////////////////////////////////
package com.puppycrawl.tools.checkstyle.checks.naming;

import com.puppycrawl.tools.checkstyle.api.DetailAST;
import com.puppycrawl.tools.checkstyle.api.TokenTypes;

/**
* <p>
 * Checks that parameter names conform to a format specified
 * by the format property. The format is a
 * {@link java.util.regex.Pattern regular expression}
 * and defaults to
 * <strong>^[a-z][a-zA-Z0-9]*$</strong>.
 * </p>
 * <p>
 * An example of how to configure the check is:
 * </p>
 * <pre>
 * &lt;module name="ParameterName"/&gt;
 * </pre>
 * <p>
  * An example of how to configure the check for names that begin with
 * a lower case letter, followed by letters, digits, and underscores is:
 * </p>
 * <pre>
 * &lt;module name="ParameterName"&gt;
 *    &lt;property name="format" value="^^[a-z](_?[a-zA-Z0-9]+)*$"/&gt;
 * &lt;/module&gt;
 * </pre>
 *
 * @author Oliver Burn
 */
public class ParameterNameCheck
    extends AbstractNameCheck
{
    /**
     * Creates a new <code>ParameterNameCheck</code> instance.
     */
    public ParameterNameCheck()
    {
        super("^[a-z][a-zA-Z0-9]*$");
    }

    @Override
    public int[] getDefaultTokens()
    {
        return new int[] {TokenTypes.PARAMETER_DEF};
    }

    @Override
    protected boolean mustCheckName(DetailAST aAST)
    {
        return !(
            (aAST.getParent() != null)
                && (aAST.getParent().getType() == TokenTypes.LITERAL_CATCH));
    }
}
