001/////////////////////////////////////////////////////////////////////////////////////////////// 002// checkstyle: Checks Java source code and other text files for adherence to a set of rules. 003// Copyright (C) 2001-2024 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 {@code catch} parameter names conform to a specified pattern. 028 * </p> 029 * <p> 030 * Default pattern has the following characteristic: 031 * </p> 032 * <ul> 033 * <li>allows names beginning with two lowercase letters followed by at least one uppercase or 034 * lowercase letter</li> 035 * <li>allows {@code e} abbreviation (suitable for exceptions end errors)</li> 036 * <li>allows {@code ex} abbreviation (suitable for exceptions)</li> 037 * <li>allows {@code t} abbreviation (suitable for throwables)</li> 038 * <li>prohibits numbered abbreviations like {@code e1} or {@code t2}</li> 039 * <li>prohibits one letter prefixes like {@code pException}</li> 040 * <li>prohibits two letter abbreviations like {@code ie} or {@code ee}</li> 041 * <li>prohibits any other characters than letters</li> 042 * </ul> 043 * <ul> 044 * <li> 045 * Property {@code format} - Sets the pattern to match valid identifiers. 046 * Type is {@code java.util.regex.Pattern}. 047 * Default value is {@code "^(e|t|ex|[a-z][a-z][a-zA-Z]+)$"}. 048 * </li> 049 * </ul> 050 * <p> 051 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker} 052 * </p> 053 * <p> 054 * Violation Message Keys: 055 * </p> 056 * <ul> 057 * <li> 058 * {@code name.invalidPattern} 059 * </li> 060 * </ul> 061 * 062 * @since 6.14 063 */ 064public class CatchParameterNameCheck extends AbstractNameCheck { 065 066 /** 067 * Creates a new {@code CatchParameterNameCheck} instance. 068 */ 069 public CatchParameterNameCheck() { 070 super("^(e|t|ex|[a-z][a-z][a-zA-Z]+)$"); 071 } 072 073 @Override 074 public int[] getDefaultTokens() { 075 return getRequiredTokens(); 076 } 077 078 @Override 079 public int[] getAcceptableTokens() { 080 return getRequiredTokens(); 081 } 082 083 @Override 084 public int[] getRequiredTokens() { 085 return new int[] {TokenTypes.PARAMETER_DEF}; 086 } 087 088 @Override 089 protected boolean mustCheckName(DetailAST ast) { 090 return ast.getParent().getType() == TokenTypes.LITERAL_CATCH; 091 } 092 093}