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1   /*
2    * Copyright (c) 2011-2024 Qulice.com
3    *
4    * All rights reserved.
5    *
6    * Redistribution and use in source and binary forms, with or without
7    * modification, are permitted provided that the following conditions
8    * are met: 1) Redistributions of source code must retain the above
9    * copyright notice, this list of conditions and the following
10   * disclaimer. 2) Redistributions in binary form must reproduce the above
11   * copyright notice, this list of conditions and the following
12   * disclaimer in the documentation and/or other materials provided
13   * with the distribution. 3) Neither the name of the Qulice.com nor
14   * the names of its contributors may be used to endorse or promote
15   * products derived from this software without specific prior written
16   * permission.
17   *
18   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
20   * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
21   * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
22   * THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
23   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
27   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
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30   */
31  package com.qulice.checkstyle;
32  
33  import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
34  import com.puppycrawl.tools.checkstyle.api.DetailAST;
35  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
36  
37  /**
38   * Checks node/closing brackets to be the last symbols on the line.
39   *
40   * <p>This is how a correct bracket structure should look like:
41   *
42   * <pre>
43   * String text = String.format(
44   *   "some text: %s",
45   *   new Foo().with(
46   *     "abc",
47   *     "foo"
48   *   )
49   * );
50   * </pre>
51   *
52   * <p>The motivation for such formatting is simple - we want to see the entire
53   * block as fast as possible. When you look at a block of code you should be
54   * able to see where it starts and where it ends. In exactly the same way
55   * we organize curled brackets.
56   *
57   * <p>In other words, when you open a bracket and can't close it at the same
58   * line - you should leave it as the last symbol at this line.
59   *
60   * @since 0.3
61   */
62  public final class BracketsStructureCheck extends AbstractCheck {
63  
64      @Override
65      public int[] getDefaultTokens() {
66          return new int[] {
67              TokenTypes.LITERAL_NEW,
68              TokenTypes.METHOD_CALL,
69          };
70      }
71  
72      @Override
73      public int[] getAcceptableTokens() {
74          return this.getDefaultTokens();
75      }
76  
77      @Override
78      public int[] getRequiredTokens() {
79          return this.getDefaultTokens();
80      }
81  
82      @Override
83      public void visitToken(final DetailAST ast) {
84          if (ast.getType() == TokenTypes.METHOD_CALL
85              || ast.getType() == TokenTypes.LITERAL_NEW) {
86              this.checkParams(ast);
87          } else {
88              final DetailAST brackets = ast.findFirstToken(TokenTypes.LPAREN);
89              if (brackets != null) {
90                  this.checkParams(brackets);
91              }
92          }
93      }
94  
95      /**
96       * Checks params statement to satisfy the rule.
97       * @param node Tree node, containing method call statement.
98       */
99      private void checkParams(final DetailAST node) {
100         final DetailAST closing = node.findFirstToken(TokenTypes.RPAREN);
101         if (closing != null) {
102             this.checkLines(node, node.getLineNo(), closing.getLineNo());
103         }
104     }
105 
106     /**
107      * Checks params statement to satisfy the rule.
108      * @param node Tree node, containing method call statement.
109      * @param start First line
110      * @param end Final line
111      */
112     private void checkLines(final DetailAST node, final int start,
113         final int end) {
114         if (start != end) {
115             final DetailAST elist = node.findFirstToken(TokenTypes.ELIST);
116             final int pline = elist.getLineNo();
117             if (pline == start) {
118                 this.log(pline, "Parameters should start on a new line");
119             }
120             this.checkExpressionList(elist, end);
121         }
122     }
123 
124     /**
125      * Checks expression list if closing bracket is on new line.
126      * @param elist Tree node, containing expression list
127      * @param end Final line
128      */
129     private void checkExpressionList(final DetailAST elist, final int end) {
130         if (elist.getChildCount() > 0) {
131             final DetailAST last = elist.getLastChild();
132             final int lline = last.getLineNo();
133             if (lline == end) {
134                 this.log(lline, "Closing bracket should be on a new line");
135             }
136         }
137     }
138 
139 }