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; 021 022import com.puppycrawl.tools.checkstyle.StatelessCheck; 023import com.puppycrawl.tools.checkstyle.api.AbstractCheck; 024import com.puppycrawl.tools.checkstyle.api.DetailAST; 025import com.puppycrawl.tools.checkstyle.api.TokenTypes; 026 027/** 028 * <p> 029 * Checks the style of array type definitions. 030 * Some like Java style: {@code public static void main(String[] args)} 031 * and some like C style: {@code public static void main(String args[])}. 032 * </p> 033 * <p> 034 * By default, the Check enforces Java style. 035 * </p> 036 * <p> 037 * This check strictly enforces only Java style for method return types regardless 038 * of the value for 'javaStyle'. For example, {@code byte[] getData()}. 039 * This is because C doesn't compile methods with array declarations on the name. 040 * </p> 041 * <ul> 042 * <li> 043 * Property {@code javaStyle} - Control whether to enforce Java style (true) or C style (false). 044 * Type is {@code boolean}. 045 * Default value is {@code true}. 046 * </li> 047 * </ul> 048 * <p> 049 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker} 050 * </p> 051 * <p> 052 * Violation Message Keys: 053 * </p> 054 * <ul> 055 * <li> 056 * {@code array.type.style} 057 * </li> 058 * </ul> 059 * 060 * @since 3.1 061 */ 062@StatelessCheck 063public class ArrayTypeStyleCheck extends AbstractCheck { 064 065 /** 066 * A key is pointing to the warning message text in "messages.properties" 067 * file. 068 */ 069 public static final String MSG_KEY = "array.type.style"; 070 071 /** Control whether to enforce Java style (true) or C style (false). */ 072 private boolean javaStyle = true; 073 074 @Override 075 public int[] getDefaultTokens() { 076 return getRequiredTokens(); 077 } 078 079 @Override 080 public int[] getAcceptableTokens() { 081 return getRequiredTokens(); 082 } 083 084 @Override 085 public int[] getRequiredTokens() { 086 return new int[] {TokenTypes.ARRAY_DECLARATOR}; 087 } 088 089 @Override 090 public void visitToken(DetailAST ast) { 091 final DetailAST typeAST = ast.getParent(); 092 final DetailAST identAst = typeAST.getNextSibling(); 093 // If identAst is null, we have a 'LITERAL_NEW' expression, i.e. 'new int[2][2]' 094 if (identAst != null) { 095 final boolean isMethod = typeAST.getParent().getType() == TokenTypes.METHOD_DEF; 096 final boolean isJavaStyle = identAst.getLineNo() > ast.getLineNo() 097 || identAst.getColumnNo() - ast.getColumnNo() > -1; 098 099 // force all methods to be Java style (see note in top Javadoc) 100 final boolean isMethodViolation = isMethod && !isJavaStyle; 101 final boolean isVariableViolation = !isMethod 102 && isJavaStyle != javaStyle; 103 104 if (isMethodViolation || isVariableViolation) { 105 log(ast, MSG_KEY); 106 } 107 } 108 } 109 110 /** 111 * Setter to control whether to enforce Java style (true) or C style (false). 112 * 113 * @param javaStyle true if Java style should be used. 114 * @since 3.1 115 */ 116 public void setJavaStyle(boolean javaStyle) { 117 this.javaStyle = javaStyle; 118 } 119 120}