Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
ReturnCountCheck |
|
| 1.7692307692307692;1.769 | ||||
ReturnCountCheck$Context |
|
| 1.7692307692307692;1.769 |
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.DetailAST; | |
22 | import com.puppycrawl.tools.checkstyle.api.FastStack; | |
23 | import com.puppycrawl.tools.checkstyle.api.TokenTypes; | |
24 | import com.puppycrawl.tools.checkstyle.checks.AbstractFormatCheck; | |
25 | ||
26 | /** | |
27 | * <p> | |
28 | * Restricts return statements to a specified count (default = 2). | |
29 | * Ignores specified methods (<code>equals()</code> by default). | |
30 | * </p> | |
31 | * <p> | |
32 | * Rationale: Too many return points can be indication that code is | |
33 | * attempting to do too much or may be difficult to understand. | |
34 | * </p> | |
35 | * | |
36 | * @author <a href="mailto:simon@redhillconsulting.com.au">Simon Harris</a> | |
37 | * TODO: Test for inside a static block | |
38 | */ | |
39 | public final class ReturnCountCheck extends AbstractFormatCheck | |
40 | { | |
41 | /** Default allowed number of return statements. */ | |
42 | private static final int DEFAULT_MAX = 2; | |
43 | ||
44 | /** Stack of method contexts. */ | |
45 | 2 | private final FastStack<Context> mContextStack = FastStack.newInstance(); |
46 | /** Maximum allowed number of return stmts. */ | |
47 | private int mMax; | |
48 | /** Current method context. */ | |
49 | private Context mContext; | |
50 | ||
51 | /** Creates new instance of the checks. */ | |
52 | public ReturnCountCheck() | |
53 | { | |
54 | 2 | super("^equals$"); |
55 | 2 | setMax(DEFAULT_MAX); |
56 | 2 | } |
57 | ||
58 | @Override | |
59 | public int[] getDefaultTokens() | |
60 | { | |
61 | 2 | return new int[] { |
62 | TokenTypes.CTOR_DEF, | |
63 | TokenTypes.METHOD_DEF, | |
64 | TokenTypes.LITERAL_RETURN, | |
65 | }; | |
66 | } | |
67 | ||
68 | @Override | |
69 | public int[] getRequiredTokens() | |
70 | { | |
71 | 0 | return new int[]{ |
72 | TokenTypes.CTOR_DEF, | |
73 | TokenTypes.METHOD_DEF, | |
74 | }; | |
75 | } | |
76 | ||
77 | /** | |
78 | * Getter for max property. | |
79 | * @return maximum allowed number of return statements. | |
80 | */ | |
81 | public int getMax() | |
82 | { | |
83 | 14 | return mMax; |
84 | } | |
85 | ||
86 | /** | |
87 | * Setter for max property. | |
88 | * @param aMax maximum allowed number of return statements. | |
89 | */ | |
90 | public void setMax(int aMax) | |
91 | { | |
92 | 2 | mMax = aMax; |
93 | 2 | } |
94 | ||
95 | @Override | |
96 | public void beginTree(DetailAST aRootAST) | |
97 | { | |
98 | 2 | mContext = null; |
99 | 2 | mContextStack.clear(); |
100 | 2 | } |
101 | ||
102 | @Override | |
103 | public void visitToken(DetailAST aAST) | |
104 | { | |
105 | 54 | switch (aAST.getType()) { |
106 | case TokenTypes.CTOR_DEF: | |
107 | case TokenTypes.METHOD_DEF: | |
108 | 10 | visitMethodDef(aAST); |
109 | 10 | break; |
110 | case TokenTypes.LITERAL_RETURN: | |
111 | 44 | mContext.visitLiteralReturn(); |
112 | 44 | break; |
113 | default: | |
114 | 0 | throw new IllegalStateException(aAST.toString()); |
115 | } | |
116 | 54 | } |
117 | ||
118 | @Override | |
119 | public void leaveToken(DetailAST aAST) | |
120 | { | |
121 | 54 | switch (aAST.getType()) { |
122 | case TokenTypes.CTOR_DEF: | |
123 | case TokenTypes.METHOD_DEF: | |
124 | 10 | leaveMethodDef(aAST); |
125 | 10 | break; |
126 | case TokenTypes.LITERAL_RETURN: | |
127 | // Do nothing | |
128 | 44 | break; |
129 | default: | |
130 | 0 | throw new IllegalStateException(aAST.toString()); |
131 | } | |
132 | 54 | } |
133 | ||
134 | /** | |
135 | * Creates new method context and places old one on the stack. | |
136 | * @param aAST method definition for check. | |
137 | */ | |
138 | private void visitMethodDef(DetailAST aAST) | |
139 | { | |
140 | 10 | mContextStack.push(mContext); |
141 | 10 | final DetailAST methodNameAST = aAST.findFirstToken(TokenTypes.IDENT); |
142 | 10 | mContext = |
143 | new Context(!getRegexp().matcher(methodNameAST.getText()).find()); | |
144 | 10 | } |
145 | ||
146 | /** | |
147 | * Checks number of return statements and restore | |
148 | * previous method context. | |
149 | * @param aAST method def node. | |
150 | */ | |
151 | private void leaveMethodDef(DetailAST aAST) | |
152 | { | |
153 | 10 | mContext.checkCount(aAST); |
154 | 10 | mContext = mContextStack.pop(); |
155 | 10 | } |
156 | ||
157 | /** | |
158 | * Class to encapsulate information about one method. | |
159 | * @author <a href="mailto:simon@redhillconsulting.com.au">Simon Harris</a> | |
160 | */ | |
161 | private class Context | |
162 | { | |
163 | /** Whether we should check this method or not. */ | |
164 | private final boolean mChecking; | |
165 | /** Counter for return statements. */ | |
166 | private int mCount; | |
167 | ||
168 | /** | |
169 | * Creates new method context. | |
170 | * @param aChecking should we check this method or not. | |
171 | */ | |
172 | public Context(boolean aChecking) | |
173 | 10 | { |
174 | 10 | mChecking = aChecking; |
175 | 10 | mCount = 0; |
176 | 10 | } |
177 | ||
178 | /** Increase number of return statements. */ | |
179 | public void visitLiteralReturn() | |
180 | { | |
181 | 44 | ++mCount; |
182 | 44 | } |
183 | ||
184 | /** | |
185 | * Checks if number of return statements in method more | |
186 | * than allowed. | |
187 | * @param aAST method def associated with this context. | |
188 | */ | |
189 | public void checkCount(DetailAST aAST) | |
190 | { | |
191 | 10 | if (mChecking && (mCount > getMax())) { |
192 | 5 | log(aAST.getLineNo(), aAST.getColumnNo(), "return.count", |
193 | mCount, getMax()); | |
194 | } | |
195 | 10 | } |
196 | } | |
197 | } |