001//////////////////////////////////////////////////////////////////////////////// 002// checkstyle: Checks Java source code for adherence to a set of rules. 003// Copyright (C) 2001-2014 Oliver Burn 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//////////////////////////////////////////////////////////////////////////////// 019package com.puppycrawl.tools.checkstyle.checks.naming; 020 021import com.puppycrawl.tools.checkstyle.api.AnnotationUtility; 022import com.puppycrawl.tools.checkstyle.api.DetailAST; 023import com.puppycrawl.tools.checkstyle.api.TokenTypes; 024 025/** 026 * <p> 027 * Checks that method names conform to a format specified 028 * by the format property. The format is a 029 * {@link java.util.regex.Pattern regular expression} 030 * and defaults to 031 * <strong>^[a-z][a-zA-Z0-9]*$</strong>. 032 * </p> 033 * 034 * <p> 035 * Also, checks if a method name has the same name as the residing class. 036 * The default is false (it is not allowed). It is legal in Java to have 037 * method with the same name as a class. As long as a return type is specified 038 * it is a method and not a constructor which it could be easily confused as. 039 * <h3>Does not check-style the name of an overriden methods</h3> because the developer does not 040 * have a choice in renaming such methods. 041 * </p> 042 * 043 * <p> 044 * An example of how to configure the check is: 045 * </p> 046 * <pre> 047 * <module name="MethodName"/> 048 * </pre> 049 * <p> 050 * An example of how to configure the check for names that begin with 051 * a lower case letter, followed by letters, digits, and underscores is: 052 * </p> 053 * <pre> 054 * <module name="MethodName"> 055 * <property name="format" value="^[a-z](_?[a-zA-Z0-9]+)*$"/> 056 * </module> 057 * </pre> 058 * 059 * <p> 060 * An example of how to configure the check to allow method names 061 * to be equal to the residing class name is: 062 * </p> 063 * <pre> 064 * <module name="MethodName"> 065 * <property name="allowClassName" value="true"/> 066 * </module> 067 * </pre> 068 * @author Oliver Burn 069 * @author Travis Schneeberger 070 * @author Utkarsh Srivastava 071 * @version 1.1 072 */ 073public class MethodNameCheck 074 extends AbstractAccessControlNameCheck 075{ 076 /** 077 * for allowing method name to be the same as the class name. 078 */ 079 private boolean allowClassName; 080 081 /** 082 * {@link Override Override} annotation name. 083 */ 084 private static final String OVERRIDE = "Override"; 085 086 /** 087 * Canonical {@link Override Override} annotation name. 088 */ 089 private static final String CANONICAL_OVERRIDE = "java.lang." + OVERRIDE; 090 091 /** Creates a new <code>MethodNameCheck</code> instance. */ 092 public MethodNameCheck() 093 { 094 super("^[a-z][a-zA-Z0-9]*$"); 095 } 096 097 @Override 098 public int[] getDefaultTokens() 099 { 100 return new int[] {TokenTypes.METHOD_DEF, }; 101 } 102 103 @Override 104 public void visitToken(DetailAST ast) 105 { 106 if (!AnnotationUtility.containsAnnotation(ast, OVERRIDE) 107 && !AnnotationUtility.containsAnnotation(ast, CANONICAL_OVERRIDE)) 108 { 109 super.visitToken(ast); // Will check the name against the format. 110 } 111 112 if (!allowClassName) { 113 final DetailAST method = 114 ast.findFirstToken(TokenTypes.IDENT); 115 //in all cases this will be the classDef type except anon inner 116 //with anon inner classes this will be the Literal_New keyword 117 final DetailAST classDefOrNew = ast.getParent().getParent(); 118 final DetailAST classIdent = 119 classDefOrNew.findFirstToken(TokenTypes.IDENT); 120 // Following logic is to handle when a classIdent can not be 121 // found. This is when you have a Literal_New keyword followed 122 // a DOT, which is when you have: 123 // new Outclass.InnerInterface(x) { ... } 124 // Such a rare case, will not have the logic to handle parsing 125 // down the tree looking for the first ident. 126 if ((null != classIdent) 127 && method.getText().equals(classIdent.getText())) 128 { 129 log(method.getLineNo(), method.getColumnNo(), 130 "method.name.equals.class.name", method.getText()); 131 } 132 } 133 } 134 135 /** 136 * Sets the property for allowing a method to be the same name as a class. 137 * @param allowClassName true to allow false to disallow 138 */ 139 public void setAllowClassName(boolean allowClassName) 140 { 141 this.allowClassName = allowClassName; 142 } 143}