1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2024 the original author or authors.
4 //
5 // This library is free software; you can redistribute it and/or
6 // modify it under the terms of the GNU Lesser General Public
7 // License as published by the Free Software Foundation; either
8 // version 2.1 of the License, or (at your option) any later version.
9 //
10 // This library is distributed in the hope that it will be useful,
11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 // Lesser General Public License for more details.
14 //
15 // You should have received a copy of the GNU Lesser General Public
16 // License along with this library; if not, write to the Free Software
17 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 ///////////////////////////////////////////////////////////////////////////////////////////////
19
20 package com.puppycrawl.tools.checkstyle.checks.coding;
21
22 import com.puppycrawl.tools.checkstyle.StatelessCheck;
23 import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
24 import com.puppycrawl.tools.checkstyle.api.DetailAST;
25 import com.puppycrawl.tools.checkstyle.api.TokenTypes;
26
27 /**
28 * <div>
29 * Detects inline conditionals. Here is one example of an inline conditional:
30 * </div>
31 * <pre>
32 * String a = getParameter("a");
33 * String b = (a==null || a.length()<1) ? null : a.substring(1);
34 * </pre>
35 *
36 * <p>
37 * Rationale: Some developers find inline conditionals hard to read, so
38 * their employer's coding standards forbid them.
39 * </p>
40 *
41 * <p>
42 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
43 * </p>
44 *
45 * <p>
46 * Violation Message Keys:
47 * </p>
48 * <ul>
49 * <li>
50 * {@code inline.conditional.avoid}
51 * </li>
52 * </ul>
53 *
54 * @since 3.1
55 */
56 @StatelessCheck
57 public class AvoidInlineConditionalsCheck extends AbstractCheck {
58
59 /**
60 * A key is pointing to the warning message text in "messages.properties"
61 * file.
62 */
63 public static final String MSG_KEY = "inline.conditional.avoid";
64
65 @Override
66 public int[] getDefaultTokens() {
67 return getRequiredTokens();
68 }
69
70 @Override
71 public int[] getRequiredTokens() {
72 return new int[] {TokenTypes.QUESTION};
73 }
74
75 @Override
76 public int[] getAcceptableTokens() {
77 return getRequiredTokens();
78 }
79
80 @Override
81 public void visitToken(DetailAST ast) {
82 // the only place a QUESTION token can occur is in inline conditionals
83 // so no need to do any further tricks here - pretty trivial Check!
84
85 log(ast, MSG_KEY);
86 }
87
88 }