001///////////////////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
003// Copyright (C) 2001-2025 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()&lt;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}