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.FileStatefulCheck;
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 * <p>
29 * Restricts nested try-catch-finally blocks to a specified depth.
30 * </p>
31 * <ul>
32 * <li>
33 * Property {@code max} - Specify maximum allowed nesting depth.
34 * Type is {@code int}.
35 * Default value is {@code 1}.
36 * </li>
37 * </ul>
38 * <p>
39 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
40 * </p>
41 * <p>
42 * Violation Message Keys:
43 * </p>
44 * <ul>
45 * <li>
46 * {@code nested.try.depth}
47 * </li>
48 * </ul>
49 *
50 * @since 3.2
51 */
52 @FileStatefulCheck
53 public final class NestedTryDepthCheck extends AbstractCheck {
54
55 /**
56 * A key is pointing to the warning message text in "messages.properties"
57 * file.
58 */
59 public static final String MSG_KEY = "nested.try.depth";
60
61 /** Specify maximum allowed nesting depth. */
62 private int max = 1;
63 /** Current nesting depth. */
64 private int depth;
65
66 /**
67 * Setter to specify maximum allowed nesting depth.
68 *
69 * @param max maximum allowed nesting depth.
70 * @since 3.2
71 */
72 public void setMax(int max) {
73 this.max = max;
74 }
75
76 @Override
77 public int[] getDefaultTokens() {
78 return getRequiredTokens();
79 }
80
81 @Override
82 public int[] getAcceptableTokens() {
83 return getRequiredTokens();
84 }
85
86 @Override
87 public int[] getRequiredTokens() {
88 return new int[] {TokenTypes.LITERAL_TRY};
89 }
90
91 @Override
92 public void visitToken(DetailAST literalTry) {
93 if (depth > max) {
94 log(literalTry, MSG_KEY, depth, max);
95 }
96 ++depth;
97 }
98
99 @Override
100 public void leaveToken(DetailAST literalTry) {
101 --depth;
102 }
103
104 }