CatchParameterNameCheck.java
///////////////////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
// Copyright (C) 2001-2024 the original author or authors.
//
// 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 {@code catch} parameter names conform to a specified pattern.
* </p>
* <p>
* Default pattern has the following characteristic:
* </p>
* <ul>
* <li>allows names beginning with two lowercase letters followed by at least one uppercase or
* lowercase letter</li>
* <li>allows {@code e} abbreviation (suitable for exceptions end errors)</li>
* <li>allows {@code ex} abbreviation (suitable for exceptions)</li>
* <li>allows {@code t} abbreviation (suitable for throwables)</li>
* <li>allows {@code _} for unnamed catch parameters</li>
* <li>prohibits numbered abbreviations like {@code e1} or {@code t2}</li>
* <li>prohibits one letter prefixes like {@code pException}</li>
* <li>prohibits two letter abbreviations like {@code ie} or {@code ee}</li>
* <li>prohibits any other characters than letters</li>
* </ul>
* <ul>
* <li>
* Property {@code format} - Sets the pattern to match valid identifiers.
* Type is {@code java.util.regex.Pattern}.
* Default value is {@code "^(e|t|ex|[a-z][a-z][a-zA-Z]+|_)$"}.
* </li>
* </ul>
* <p>
* Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
* </p>
* <p>
* Violation Message Keys:
* </p>
* <ul>
* <li>
* {@code name.invalidPattern}
* </li>
* </ul>
*
* @since 6.14
*/
public class CatchParameterNameCheck extends AbstractNameCheck {
/**
* Creates a new {@code CatchParameterNameCheck} instance.
*/
public CatchParameterNameCheck() {
super("^(e|t|ex|[a-z][a-z][a-zA-Z]+|_)$");
}
@Override
public int[] getDefaultTokens() {
return getRequiredTokens();
}
@Override
public int[] getAcceptableTokens() {
return getRequiredTokens();
}
@Override
public int[] getRequiredTokens() {
return new int[] {TokenTypes.PARAMETER_DEF};
}
@Override
protected boolean mustCheckName(DetailAST ast) {
return ast.getParent().getType() == TokenTypes.LITERAL_CATCH;
}
}