1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2024 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.sizes;
21
22 import java.util.ArrayDeque;
23 import java.util.Deque;
24
25 import com.puppycrawl.tools.checkstyle.FileStatefulCheck;
26 import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
27 import com.puppycrawl.tools.checkstyle.api.DetailAST;
28 import com.puppycrawl.tools.checkstyle.api.TokenTypes;
29 import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
30
31 /**
32 * <p>
33 * Restricts the number of executable statements to a specified limit.
34 * </p>
35 * <ul>
36 * <li>
37 * Property {@code max} - Specify the maximum threshold allowed.
38 * Type is {@code int}.
39 * Default value is {@code 30}.
40 * </li>
41 * <li>
42 * Property {@code tokens} - tokens to check
43 * Type is {@code java.lang.String[]}.
44 * Validation type is {@code tokenSet}.
45 * Default value is:
46 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#CTOR_DEF">
47 * CTOR_DEF</a>,
48 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#METHOD_DEF">
49 * METHOD_DEF</a>,
50 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#INSTANCE_INIT">
51 * INSTANCE_INIT</a>,
52 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#STATIC_INIT">
53 * STATIC_INIT</a>,
54 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#COMPACT_CTOR_DEF">
55 * COMPACT_CTOR_DEF</a>,
56 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LAMBDA">
57 * LAMBDA</a>.
58 * </li>
59 * </ul>
60 * <p>
61 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
62 * </p>
63 * <p>
64 * Violation Message Keys:
65 * </p>
66 * <ul>
67 * <li>
68 * {@code executableStatementCount}
69 * </li>
70 * </ul>
71 *
72 * @since 3.2
73 */
74 @FileStatefulCheck
75 public final class ExecutableStatementCountCheck
76 extends AbstractCheck {
77
78 /**
79 * A key is pointing to the warning message text in "messages.properties"
80 * file.
81 */
82 public static final String MSG_KEY = "executableStatementCount";
83
84 /** Default threshold. */
85 private static final int DEFAULT_MAX = 30;
86
87 /** Stack of method contexts. */
88 private final Deque<Context> contextStack = new ArrayDeque<>();
89
90 /** Specify the maximum threshold allowed. */
91 private int max;
92
93 /** Current method context. */
94 private Context context;
95
96 /** Constructs a {@code ExecutableStatementCountCheck}. */
97 public ExecutableStatementCountCheck() {
98 max = DEFAULT_MAX;
99 }
100
101 @Override
102 public int[] getDefaultTokens() {
103 return new int[] {
104 TokenTypes.CTOR_DEF,
105 TokenTypes.METHOD_DEF,
106 TokenTypes.INSTANCE_INIT,
107 TokenTypes.STATIC_INIT,
108 TokenTypes.SLIST,
109 TokenTypes.COMPACT_CTOR_DEF,
110 TokenTypes.LAMBDA,
111 };
112 }
113
114 @Override
115 public int[] getRequiredTokens() {
116 return new int[] {TokenTypes.SLIST};
117 }
118
119 @Override
120 public int[] getAcceptableTokens() {
121 return new int[] {
122 TokenTypes.CTOR_DEF,
123 TokenTypes.METHOD_DEF,
124 TokenTypes.INSTANCE_INIT,
125 TokenTypes.STATIC_INIT,
126 TokenTypes.SLIST,
127 TokenTypes.COMPACT_CTOR_DEF,
128 TokenTypes.LAMBDA,
129 };
130 }
131
132 /**
133 * Setter to specify the maximum threshold allowed.
134 *
135 * @param max the maximum threshold.
136 * @since 3.2
137 */
138 public void setMax(int max) {
139 this.max = max;
140 }
141
142 @Override
143 public void beginTree(DetailAST rootAST) {
144 context = new Context(null);
145 contextStack.clear();
146 }
147
148 @Override
149 public void visitToken(DetailAST ast) {
150 if (isContainerNode(ast)) {
151 visitContainerNode(ast);
152 }
153 else if (TokenUtil.isOfType(ast, TokenTypes.SLIST)) {
154 visitSlist(ast);
155 }
156 else {
157 throw new IllegalStateException(ast.toString());
158 }
159 }
160
161 @Override
162 public void leaveToken(DetailAST ast) {
163 if (isContainerNode(ast)) {
164 leaveContainerNode(ast);
165 }
166 else if (!TokenUtil.isOfType(ast, TokenTypes.SLIST)) {
167 throw new IllegalStateException(ast.toString());
168 }
169 }
170
171 /**
172 * Process the start of the container node.
173 *
174 * @param ast the token representing the container node.
175 */
176 private void visitContainerNode(DetailAST ast) {
177 contextStack.push(context);
178 context = new Context(ast);
179 }
180
181 /**
182 * Process the end of a container node.
183 *
184 * @param ast the token representing the container node.
185 */
186 private void leaveContainerNode(DetailAST ast) {
187 final int count = context.getCount();
188 if (count > max) {
189 log(ast, MSG_KEY, count, max);
190 }
191 context = contextStack.pop();
192 }
193
194 /**
195 * Process the end of a statement list.
196 *
197 * @param ast the token representing the statement list.
198 */
199 private void visitSlist(DetailAST ast) {
200 final DetailAST contextAST = context.getAST();
201 DetailAST parent = ast;
202 while (parent != null && !isContainerNode(parent)) {
203 parent = parent.getParent();
204 }
205 if (parent == contextAST) {
206 context.addCount(ast.getChildCount() / 2);
207 }
208 }
209
210 /**
211 * Check if the node is of type ctor (compact or canonical),
212 * instance/ static initializer, method definition or lambda.
213 *
214 * @param node AST node we are checking
215 * @return true if node is of the given types
216 */
217 private static boolean isContainerNode(DetailAST node) {
218 return TokenUtil.isOfType(node, TokenTypes.METHOD_DEF,
219 TokenTypes.LAMBDA, TokenTypes.CTOR_DEF, TokenTypes.INSTANCE_INIT,
220 TokenTypes.STATIC_INIT, TokenTypes.COMPACT_CTOR_DEF);
221 }
222
223 /**
224 * Class to encapsulate counting information about one member.
225 */
226 private static final class Context {
227
228 /** Member AST node. */
229 private final DetailAST ast;
230
231 /** Counter for context elements. */
232 private int count;
233
234 /**
235 * Creates new member context.
236 *
237 * @param ast member AST node.
238 */
239 private Context(DetailAST ast) {
240 this.ast = ast;
241 }
242
243 /**
244 * Increase count.
245 *
246 * @param addition the count increment.
247 */
248 public void addCount(int addition) {
249 count += addition;
250 }
251
252 /**
253 * Gets the member AST node.
254 *
255 * @return the member AST node.
256 */
257 public DetailAST getAST() {
258 return ast;
259 }
260
261 /**
262 * Gets the count.
263 *
264 * @return the count.
265 */
266 public int getCount() {
267 return count;
268 }
269
270 }
271
272 }