Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
MultipleVariableDeclarationsCheck |
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| 4.75;4.75 |
1 | //////////////////////////////////////////////////////////////////////////////// | |
2 | // checkstyle: Checks Java source code for adherence to a set of rules. | |
3 | // Copyright (C) 2001-2014 Oliver Burn | |
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 | package com.puppycrawl.tools.checkstyle.checks.coding; | |
20 | ||
21 | import com.puppycrawl.tools.checkstyle.api.Check; | |
22 | import com.puppycrawl.tools.checkstyle.api.DetailAST; | |
23 | import com.puppycrawl.tools.checkstyle.api.TokenTypes; | |
24 | import com.puppycrawl.tools.checkstyle.checks.CheckUtils; | |
25 | ||
26 | /** | |
27 | * <p> | |
28 | * Checks that each variable declaration is in its own statement | |
29 | * and on its own line. | |
30 | * </p> | |
31 | * <p> | |
32 | * Rationale: <a | |
33 | * href="http://java.sun.com/docs/codeconv/html/CodeConventions.doc5.html#2991"> | |
34 | * the SUN Code conventions chapter 6.1</a> recommends that | |
35 | * declarations should be one per line. | |
36 | * </p> | |
37 | * <p> | |
38 | * An example of how to configure the check is: | |
39 | * </p> | |
40 | * <pre> | |
41 | * <module name="MultipleVariableDeclarations"/> | |
42 | * </pre> | |
43 | * @author o_sukhodolsky | |
44 | */ | |
45 | public class MultipleVariableDeclarationsCheck extends Check | |
46 | { | |
47 | /** Creates new instance of the check. */ | |
48 | public MultipleVariableDeclarationsCheck() | |
49 | 1 | { |
50 | 1 | } |
51 | ||
52 | @Override | |
53 | public int[] getDefaultTokens() | |
54 | { | |
55 | 1 | return new int[] {TokenTypes.VARIABLE_DEF}; |
56 | } | |
57 | ||
58 | @Override | |
59 | public void visitToken(DetailAST aAST) | |
60 | { | |
61 | 15 | DetailAST nextNode = aAST.getNextSibling(); |
62 | 15 | final boolean isCommaSeparated = |
63 | ((nextNode != null) && (nextNode.getType() == TokenTypes.COMMA)); | |
64 | ||
65 | 15 | if (nextNode == null) { |
66 | // no next statement - no check | |
67 | 2 | return; |
68 | } | |
69 | ||
70 | 13 | if ((nextNode.getType() == TokenTypes.COMMA) |
71 | || (nextNode.getType() == TokenTypes.SEMI)) | |
72 | { | |
73 | 6 | nextNode = nextNode.getNextSibling(); |
74 | } | |
75 | ||
76 | 13 | if ((nextNode != null) |
77 | && (nextNode.getType() == TokenTypes.VARIABLE_DEF)) | |
78 | { | |
79 | 10 | final DetailAST firstNode = CheckUtils.getFirstNode(aAST); |
80 | 10 | if (isCommaSeparated) { |
81 | // Check if the multiple variable declarations are in a | |
82 | // for loop initializer. If they are, then no warning | |
83 | // should be displayed. Declaring multiple variables in | |
84 | // a for loop initializer is a good way to minimize | |
85 | // variable scope. Refer Feature Request Id - 2895985 | |
86 | // for more details | |
87 | 3 | if (aAST.getParent().getType() != TokenTypes.FOR_INIT) { |
88 | 2 | log(firstNode, "multiple.variable.declarations.comma"); |
89 | } | |
90 | 3 | return; |
91 | } | |
92 | ||
93 | 7 | final DetailAST lastNode = getLastNode(aAST); |
94 | 7 | final DetailAST firstNextNode = CheckUtils.getFirstNode(nextNode); |
95 | ||
96 | 7 | if (firstNextNode.getLineNo() == lastNode.getLineNo()) { |
97 | 4 | log(firstNode, "multiple.variable.declarations"); |
98 | } | |
99 | } | |
100 | ||
101 | 10 | } |
102 | ||
103 | /** | |
104 | * Finds sub-node for given node maximum (line, column) pair. | |
105 | * @param aNode the root of tree for search. | |
106 | * @return sub-node with maximum (line, column) pair. | |
107 | */ | |
108 | private static DetailAST getLastNode(final DetailAST aNode) | |
109 | { | |
110 | 57 | DetailAST currentNode = aNode; |
111 | 57 | DetailAST child = aNode.getFirstChild(); |
112 | 107 | while (child != null) { |
113 | 50 | final DetailAST newNode = getLastNode(child); |
114 | 50 | if ((newNode.getLineNo() > currentNode.getLineNo()) |
115 | || ((newNode.getLineNo() == currentNode.getLineNo()) | |
116 | && (newNode.getColumnNo() > currentNode.getColumnNo()))) | |
117 | { | |
118 | 27 | currentNode = newNode; |
119 | } | |
120 | 50 | child = child.getNextSibling(); |
121 | 50 | } |
122 | ||
123 | 57 | return currentNode; |
124 | } | |
125 | } |