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.coding; 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 * <div> 029 * Detects inline conditionals. Here is one example of an inline conditional: 030 * </div> 031 * <pre> 032 * String a = getParameter("a"); 033 * String b = (a==null || a.length()<1) ? null : a.substring(1); 034 * </pre> 035 * 036 * <p> 037 * Rationale: Some developers find inline conditionals hard to read, so 038 * their employer's coding standards forbid them. 039 * </p> 040 * 041 * <p> 042 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker} 043 * </p> 044 * 045 * <p> 046 * Violation Message Keys: 047 * </p> 048 * <ul> 049 * <li> 050 * {@code inline.conditional.avoid} 051 * </li> 052 * </ul> 053 * 054 * @since 3.1 055 */ 056@StatelessCheck 057public class AvoidInlineConditionalsCheck extends AbstractCheck { 058 059 /** 060 * A key is pointing to the warning message text in "messages.properties" 061 * file. 062 */ 063 public static final String MSG_KEY = "inline.conditional.avoid"; 064 065 @Override 066 public int[] getDefaultTokens() { 067 return getRequiredTokens(); 068 } 069 070 @Override 071 public int[] getRequiredTokens() { 072 return new int[] {TokenTypes.QUESTION}; 073 } 074 075 @Override 076 public int[] getAcceptableTokens() { 077 return getRequiredTokens(); 078 } 079 080 @Override 081 public void visitToken(DetailAST ast) { 082 // the only place a QUESTION token can occur is in inline conditionals 083 // so no need to do any further tricks here - pretty trivial Check! 084 085 log(ast, MSG_KEY); 086 } 087 088}