View Javadoc
1   ////////////////////////////////////////////////////////////////////////////////
2   // checkstyle: Checks Java source code for adherence to a set of rules.
3   // Copyright (C) 2001-2018 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  import com.puppycrawl.tools.checkstyle.utils.CheckUtils;
27  
28  /**
29   * Restricts nested if-else blocks to a specified depth (default = 1).
30   *
31   * @author <a href="mailto:simon@redhillconsulting.com.au">Simon Harris</a>
32   */
33  @FileStatefulCheck
34  public final class NestedIfDepthCheck extends AbstractCheck {
35  
36      /**
37       * A key is pointing to the warning message text in "messages.properties"
38       * file.
39       */
40      public static final String MSG_KEY = "nested.if.depth";
41  
42      /** Maximum allowed nesting depth. */
43      private int max = 1;
44      /** Current nesting depth. */
45      private int depth;
46  
47      /**
48       * Setter for maximum allowed nesting depth.
49       * @param max maximum allowed nesting depth.
50       */
51      public void setMax(int max) {
52          this.max = max;
53      }
54  
55      @Override
56      public int[] getDefaultTokens() {
57          return getRequiredTokens();
58      }
59  
60      @Override
61      public int[] getAcceptableTokens() {
62          return getRequiredTokens();
63      }
64  
65      @Override
66      public int[] getRequiredTokens() {
67          return new int[] {TokenTypes.LITERAL_IF};
68      }
69  
70      @Override
71      public void beginTree(DetailAST rootAST) {
72          depth = 0;
73      }
74  
75      @Override
76      public void visitToken(DetailAST literalIf) {
77          if (!CheckUtils.isElseIf(literalIf)) {
78              if (depth > max) {
79                  log(literalIf, MSG_KEY, depth, max);
80              }
81              ++depth;
82          }
83      }
84  
85      @Override
86      public void leaveToken(DetailAST literalIf) {
87          if (!CheckUtils.isElseIf(literalIf)) {
88              --depth;
89          }
90      }
91  
92  }