001//////////////////////////////////////////////////////////////////////////////// 002// checkstyle: Checks Java source code for adherence to a set of rules. 003// Copyright (C) 2001-2016 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 java.util.Optional; 023 024import com.puppycrawl.tools.checkstyle.api.DetailAST; 025import com.puppycrawl.tools.checkstyle.api.TokenTypes; 026import com.puppycrawl.tools.checkstyle.utils.CheckUtils; 027 028/** 029* <p> 030 * Checks that method and <code>catch</code> parameter names conform to a format specified 031 * by the format property. The format is a 032 * {@link java.util.regex.Pattern regular expression} 033 * and defaults to 034 * <strong>^[a-z][a-zA-Z0-9]*$</strong>. 035 * </p> 036 * <p>The check has the following option:</p> 037 * <p><b>ignoreOverridden</b> - allows to skip methods with Override annotation from 038 * validation. Default values is <b>false</b> .</p> 039 * <p> 040 * An example of how to configure the check is: 041 * </p> 042 * <pre> 043 * <module name="ParameterName"/> 044 * </pre> 045 * <p> 046 * An example of how to configure the check for names that begin with 047 * a lower case letter, followed by letters, digits, and underscores is: 048 * </p> 049 * <pre> 050 * <module name="ParameterName"> 051 * <property name="format" value="^[a-z][_a-zA-Z0-9]+$"/> 052 * </module> 053 * </pre> 054 * <p> 055 * An example of how to configure the check to skip methods with Override annotation from 056 * validation: 057 * </p> 058 * <pre> 059 * <module name="ParameterName"> 060 * <property name="ignoreOverridden" value="true"/> 061 * </module> 062 * </pre> 063 * 064 * @author Oliver Burn 065 * @author Andrei Selkin 066 */ 067public class ParameterNameCheck 068 extends AbstractNameCheck { 069 070 /** 071 * Allows to skip methods with Override annotation from validation. 072 */ 073 private boolean ignoreOverridden; 074 075 /** 076 * Creates a new {@code ParameterNameCheck} instance. 077 */ 078 public ParameterNameCheck() { 079 super("^[a-z][a-zA-Z0-9]*$"); 080 } 081 082 /** 083 * Sets whether to skip methods with Override annotation from validation. 084 * 085 * @param ignoreOverridden Flag for skipping methods with Override annotation. 086 */ 087 public void setIgnoreOverridden(boolean ignoreOverridden) { 088 this.ignoreOverridden = ignoreOverridden; 089 } 090 091 @Override 092 public int[] getDefaultTokens() { 093 return getAcceptableTokens(); 094 } 095 096 @Override 097 public int[] getAcceptableTokens() { 098 return new int[] {TokenTypes.PARAMETER_DEF}; 099 } 100 101 @Override 102 public int[] getRequiredTokens() { 103 return getAcceptableTokens(); 104 } 105 106 @Override 107 protected boolean mustCheckName(DetailAST ast) { 108 boolean checkName = true; 109 if (ignoreOverridden && isOverriddenMethod(ast) 110 || ast.getParent().getType() == TokenTypes.LITERAL_CATCH 111 || CheckUtils.isReceiverParameter(ast)) { 112 checkName = false; 113 } 114 return checkName; 115 } 116 117 /** 118 * Checks whether a method is annotated with Override annotation. 119 * @param ast method parameter definition token. 120 * @return true if a method is annotated with Override annotation. 121 */ 122 private static boolean isOverriddenMethod(DetailAST ast) { 123 boolean overridden = false; 124 125 final DetailAST parent = ast.getParent().getParent(); 126 final Optional<DetailAST> annotation = 127 Optional.ofNullable(parent.getFirstChild().getFirstChild()); 128 129 if (annotation.isPresent() && annotation.get().getType() == TokenTypes.ANNOTATION) { 130 final Optional<DetailAST> overrideToken = 131 Optional.ofNullable(annotation.get().findFirstToken(TokenTypes.IDENT)); 132 if (overrideToken.isPresent() && "Override".equals(overrideToken.get().getText())) { 133 overridden = true; 134 } 135 } 136 return overridden; 137 } 138}