1   ////////////////////////////////////////////////////////////////////////////////
2   // checkstyle: Checks Java source code for adherence to a set of rules.
3   // Copyright (C) 2001-2019 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.indentation;
21  
22  import java.util.Arrays;
23  
24  import com.puppycrawl.tools.checkstyle.api.DetailAST;
25  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
26  
27  /**
28   * Handler for a list of statements.
29   *
30   */
31  public class SlistHandler extends BlockParentHandler {
32  
33      /**
34       * Parent token types.
35       */
36      private static final int[] PARENT_TOKEN_TYPES = {
37          TokenTypes.CTOR_DEF,
38          TokenTypes.METHOD_DEF,
39          TokenTypes.STATIC_INIT,
40          TokenTypes.LITERAL_SYNCHRONIZED,
41          TokenTypes.LITERAL_IF,
42          TokenTypes.LITERAL_WHILE,
43          TokenTypes.LITERAL_DO,
44          TokenTypes.LITERAL_FOR,
45          TokenTypes.LITERAL_ELSE,
46          TokenTypes.LITERAL_TRY,
47          TokenTypes.LITERAL_CATCH,
48          TokenTypes.LITERAL_FINALLY,
49      };
50  
51      static {
52          // Array sorting for binary search
53          Arrays.sort(PARENT_TOKEN_TYPES);
54      }
55  
56      /**
57       * Construct an instance of this handler with the given indentation check,
58       * abstract syntax tree, and parent handler.
59       *
60       * @param indentCheck   the indentation check
61       * @param ast           the abstract syntax tree
62       * @param parent        the parent handler
63       */
64      public SlistHandler(IndentationCheck indentCheck,
65          DetailAST ast, AbstractExpressionHandler parent) {
66          super(indentCheck, "block", ast, parent);
67      }
68  
69      @Override
70      public IndentLevel getSuggestedChildIndent(AbstractExpressionHandler child) {
71          // this is:
72          //  switch (var) {
73          //     case 3: {
74          //        break;
75          //     }
76          //  }
77          //  ... the case SLIST is followed by a user-created SLIST and
78          //  preceded by a switch
79  
80          final IndentLevel result;
81          // if our parent is a block handler we want to be transparent
82          if (getParent() instanceof BlockParentHandler
83                  && !(getParent() instanceof SlistHandler)
84              || child instanceof SlistHandler
85                  && getParent() instanceof CaseHandler) {
86              result = getParent().getSuggestedChildIndent(child);
87          }
88          else {
89              result = super.getSuggestedChildIndent(child);
90          }
91          return result;
92      }
93  
94      @Override
95      protected DetailAST getListChild() {
96          return getMainAst();
97      }
98  
99      @Override
100     protected DetailAST getLeftCurly() {
101         return getMainAst();
102     }
103 
104     @Override
105     protected DetailAST getRightCurly() {
106         return getMainAst().findFirstToken(TokenTypes.RCURLY);
107     }
108 
109     @Override
110     protected DetailAST getTopLevelAst() {
111         return null;
112     }
113 
114     /**
115      * Determine if the expression we are handling has a block parent.
116      *
117      * @return true if it does, false otherwise
118      */
119     private boolean hasBlockParent() {
120         final int parentType = getMainAst().getParent().getType();
121         return Arrays.binarySearch(PARENT_TOKEN_TYPES, parentType) >= 0;
122     }
123 
124     @Override
125     public void checkIndentation() {
126         // only need to check this if parent is not
127         // an if, else, while, do, ctor, method
128         if (!hasBlockParent() && !isSameLineCaseGroup()) {
129             super.checkIndentation();
130         }
131     }
132 
133     /**
134      * Checks if SLIST node is placed at the same line as CASE_GROUP node.
135      * @return true, if SLIST node is places at the same line as CASE_GROUP node.
136      */
137     private boolean isSameLineCaseGroup() {
138         final DetailAST parentNode = getMainAst().getParent();
139         return parentNode.getType() == TokenTypes.CASE_GROUP
140             && getMainAst().getLineNo() == parentNode.getLineNo();
141     }
142 
143 }