Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
AvoidStaticImportCheck |
|
| 3.25;3.25 |
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.imports; | |
20 | ||
21 | import com.puppycrawl.tools.checkstyle.api.Check; | |
22 | import com.puppycrawl.tools.checkstyle.api.DetailAST; | |
23 | import com.puppycrawl.tools.checkstyle.api.FullIdent; | |
24 | import com.puppycrawl.tools.checkstyle.api.TokenTypes; | |
25 | ||
26 | /** | |
27 | * <p> | |
28 | * Check that finds static imports. | |
29 | * </p> | |
30 | * <p> | |
31 | * Rationale: Importing static members can lead to naming conflicts | |
32 | * between class' members. It may lead to poor code readability since it | |
33 | * may no longer be clear what class a member resides (without looking | |
34 | * at the import statement). | |
35 | * </p> | |
36 | * <p> | |
37 | * An example of how to configure the check is: | |
38 | * </p> | |
39 | * <pre> | |
40 | * <module name="AvoidStaticImport"> | |
41 | * <property name="excludes" | |
42 | * value="java.lang.System.out,java.lang.Math.*"/> | |
43 | * </module> | |
44 | * </pre> | |
45 | * | |
46 | * The optional "excludes" property allows for certain classes via a star | |
47 | * notation to be excluded such as java.lang.Math.* or specific | |
48 | * static members to be excluded like java.lang.System.out for a variable | |
49 | * or java.lang.Math.random for a method. | |
50 | * | |
51 | * <p> | |
52 | * If you exclude a starred import on a class this automatically | |
53 | * excludes each member individually. | |
54 | * </p> | |
55 | * | |
56 | * <p> | |
57 | * For example: | |
58 | * Excluding java.lang.Math.* will allow the import of | |
59 | * each static member in the Math class individually like | |
60 | * java.lang.Math.PI | |
61 | * </p> | |
62 | * @author Travis Schneeberger | |
63 | * @version 1.0 | |
64 | */ | |
65 | 4 | public class AvoidStaticImportCheck |
66 | extends Check | |
67 | { | |
68 | /** the classes/static members to exempt from this check. */ | |
69 | 4 | private String[] mExcludes = new String[0]; |
70 | ||
71 | @Override | |
72 | public int[] getDefaultTokens() | |
73 | { | |
74 | 4 | return new int[] {TokenTypes.STATIC_IMPORT}; |
75 | } | |
76 | ||
77 | /** | |
78 | * Sets the list of classes or static members to be exempt from the check. | |
79 | * @param aExcludes a list of fully-qualified class names/specific | |
80 | * static members where static imports are ok | |
81 | */ | |
82 | public void setExcludes(String[] aExcludes) | |
83 | { | |
84 | 3 | mExcludes = aExcludes.clone(); |
85 | 3 | } |
86 | ||
87 | @Override | |
88 | public void visitToken(final DetailAST aAST) | |
89 | { | |
90 | 20 | final DetailAST startingDot = |
91 | aAST.getFirstChild().getNextSibling(); | |
92 | 20 | final FullIdent name = FullIdent.createFullIdent(startingDot); |
93 | ||
94 | 20 | if ((null != name) && !isExempt(name.getText())) { |
95 | 16 | log(startingDot.getLineNo(), "import.avoidStatic", name.getText()); |
96 | } | |
97 | 20 | } |
98 | ||
99 | /** | |
100 | * Checks if a class or static member is exempt from known excludes. | |
101 | * | |
102 | * @param aClassOrStaticMember | |
103 | * the class or static member | |
104 | * @return true if except false if not | |
105 | */ | |
106 | private boolean isExempt(String aClassOrStaticMember) | |
107 | { | |
108 | 54 | for (String exclude : mExcludes) { |
109 | 38 | if (aClassOrStaticMember.equals(exclude)) { |
110 | 2 | return true; |
111 | } | |
112 | 36 | else if (exclude.endsWith(".*")) { |
113 | //this section allows explicit imports | |
114 | //to be exempt when configured using | |
115 | //a starred import | |
116 | 7 | final String excludeMinusDotStar = |
117 | exclude.substring(0, exclude.length() - 2); | |
118 | 7 | if (aClassOrStaticMember.startsWith(excludeMinusDotStar)) { |
119 | 2 | final String member = |
120 | aClassOrStaticMember.substring( | |
121 | excludeMinusDotStar.length() + 1); | |
122 | //if it contains a dot then it is not a member but a package | |
123 | 2 | if (member.indexOf('.') == -1) { |
124 | 2 | return true; |
125 | } | |
126 | } | |
127 | } | |
128 | } | |
129 | 16 | return false; |
130 | } | |
131 | } |