1 /*
2 * Copyright (c) 2005, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.code;
27
28 import java.util.EnumSet;
29 import java.util.Map;
30 import java.util.concurrent.ConcurrentHashMap;
31
32 import com.sun.tools.javac.code.Symbol.*;
33 import com.sun.tools.javac.util.Context;
34 import com.sun.tools.javac.util.List;
35 import com.sun.tools.javac.util.Options;
36 import com.sun.tools.javac.util.Pair;
37
38 /**
39 * A class for handling -Xlint suboptions and @SuppresssWarnings.
40 *
41 * <p><b>This is NOT part of any supported API.
42 * If you write code that depends on this, you do so at your own risk.
43 * This code and its internal interfaces are subject to change or
44 * deletion without notice.</b>
45 */
46 public class Lint
47 {
48 /** The context key for the root Lint object. */
49 protected static final Context.Key<Lint> lintKey = new Context.Key<>();
50
51 /** Get the root Lint instance. */
52 public static Lint instance(Context context) {
53 Lint instance = context.get(lintKey);
54 if (instance == null)
55 instance = new Lint(context);
56 return instance;
57 }
58
59 /**
60 * Returns the result of combining the values in this object with
61 * the given annotation.
62 */
63 public Lint augment(Attribute.Compound attr) {
64 return augmentor.augment(this, attr);
65 }
66
67
68 /**
69 * Returns the result of combining the values in this object with
70 * the metadata on the given symbol.
71 */
72 public Lint augment(Symbol sym) {
73 Lint l = augmentor.augment(this, sym.getDeclarationAttributes());
74 if (sym.isDeprecated()) {
75 if (l == this)
76 l = new Lint(this);
77 l.values.remove(LintCategory.DEPRECATION);
78 l.suppressedValues.add(LintCategory.DEPRECATION);
79 }
80 return l;
81 }
82
83 /**
84 * Returns a new Lint that has the given LintCategory suppressed.
85 */
86 public Lint suppress(LintCategory lc) {
87 Lint l = new Lint(this);
88 l.values.remove(lc);
89 l.suppressedValues.add(lc);
90 return l;
91 }
92
93 private final AugmentVisitor augmentor;
94
95 private final EnumSet<LintCategory> values;
96 private final EnumSet<LintCategory> suppressedValues;
97
98 private static final Map<String, LintCategory> map = new ConcurrentHashMap<>(20);
99
100 protected Lint(Context context) {
101 // initialize values according to the lint options
102 Options options = Options.instance(context);
103 values = EnumSet.noneOf(LintCategory.class);
104 for (Map.Entry<String, LintCategory> e: map.entrySet()) {
105 if (options.lint(e.getKey()))
106 values.add(e.getValue());
107 }
108
109 suppressedValues = EnumSet.noneOf(LintCategory.class);
110
111 context.put(lintKey, this);
112 augmentor = new AugmentVisitor(context);
113 }
114
115 protected Lint(Lint other) {
116 this.augmentor = other.augmentor;
117 this.values = other.values.clone();
118 this.suppressedValues = other.suppressedValues.clone();
119 }
120
121 @Override
122 public String toString() {
123 return "Lint:[values" + values + " suppressedValues" + suppressedValues + "]";
124 }
125
126 /**
127 * Categories of warnings that can be generated by the compiler.
128 */
129 public enum LintCategory {
130 /**
131 * Warn when code refers to a auxiliary class that is hidden in a source file (ie source file name is
132 * different from the class name, and the type is not properly nested) and the referring code
133 * is not located in the same source file.
134 */
135 AUXILIARYCLASS("auxiliaryclass"),
136
137 /**
138 * Warn about use of unnecessary casts.
139 */
140 CAST("cast"),
141
142 /**
143 * Warn about issues related to classfile contents
144 */
145 CLASSFILE("classfile"),
146
147 /**
148 * Warn about use of deprecated items.
149 */
150 DEPRECATION("deprecation"),
151
152 /**
153 * Warn about items which are documented with an {@code @deprecated} JavaDoc
154 * comment, but which do not have {@code @Deprecated} annotation.
155 */
156 DEP_ANN("dep-ann"),
157
158 /**
159 * Warn about division by constant integer 0.
160 */
161 DIVZERO("divzero"),
162
163 /**
164 * Warn about empty statement after if.
165 */
166 EMPTY("empty"),
167
168 /**
169 * Warn about falling through from one case of a switch statement to the next.
170 */
171 FALLTHROUGH("fallthrough"),
172
173 /**
174 * Warn about finally clauses that do not terminate normally.
175 */
176 FINALLY("finally"),
177
178 /**
179 * Warn about issues relating to use of command line options
180 */
181 OPTIONS("options"),
182
183 /**
184 * Warn about issues regarding method overloads.
185 */
186 OVERLOADS("overloads"),
187
188 /**
189 * Warn about issues regarding method overrides.
190 */
191 OVERRIDES("overrides"),
192
193 /**
194 * Warn about invalid path elements on the command line.
195 * Such warnings cannot be suppressed with the SuppressWarnings
196 * annotation.
197 */
198 PATH("path"),
199
200 /**
201 * Warn about issues regarding annotation processing.
202 */
203 PROCESSING("processing"),
204
205 /**
206 * Warn about unchecked operations on raw types.
207 */
208 RAW("rawtypes"),
209
210 /**
211 * Warn about Serializable classes that do not provide a serial version ID.
212 */
213 SERIAL("serial"),
214
215 /**
216 * Warn about issues relating to use of statics
217 */
218 STATIC("static"),
219
220 /**
221 * Warn about issues relating to use of try blocks (i.e. try-with-resources)
222 */
223 TRY("try"),
224
225 /**
226 * Warn about unchecked operations on raw types.
227 */
228 UNCHECKED("unchecked"),
229
230 /**
231 * Warn about potentially unsafe vararg methods
232 */
233 VARARGS("varargs");
234
235 LintCategory(String option) {
236 this(option, false);
237 }
238
239 LintCategory(String option, boolean hidden) {
240 this.option = option;
241 this.hidden = hidden;
242 map.put(option, this);
243 }
244
245 static LintCategory get(String option) {
246 return map.get(option);
247 }
248
249 public final String option;
250 public final boolean hidden;
251 }
252
253 /**
254 * Checks if a warning category is enabled. A warning category may be enabled
255 * on the command line, or by default, and can be temporarily disabled with
256 * the SuppressWarnings annotation.
257 */
258 public boolean isEnabled(LintCategory lc) {
259 return values.contains(lc);
260 }
261
262 /**
263 * Checks is a warning category has been specifically suppressed, by means
264 * of the SuppressWarnings annotation, or, in the case of the deprecated
265 * category, whether it has been implicitly suppressed by virtue of the
266 * current entity being itself deprecated.
267 */
268 public boolean isSuppressed(LintCategory lc) {
269 return suppressedValues.contains(lc);
270 }
271
272 protected static class AugmentVisitor implements Attribute.Visitor {
273 private final Context context;
274 private Symtab syms;
275 private Lint parent;
276 private Lint lint;
277
278 AugmentVisitor(Context context) {
279 // to break an ugly sequence of initialization dependencies,
280 // we defer the initialization of syms until it is needed
281 this.context = context;
282 }
283
284 Lint augment(Lint parent, Attribute.Compound attr) {
285 initSyms();
286 this.parent = parent;
287 lint = null;
288 attr.accept(this);
289 return (lint == null ? parent : lint);
290 }
291
292 Lint augment(Lint parent, List<Attribute.Compound> attrs) {
293 initSyms();
294 this.parent = parent;
295 lint = null;
296 for (Attribute.Compound a: attrs) {
297 a.accept(this);
298 }
299 return (lint == null ? parent : lint);
300 }
301
302 private void initSyms() {
303 if (syms == null)
304 syms = Symtab.instance(context);
305 }
306
307 private void suppress(LintCategory lc) {
308 if (lint == null)
309 lint = new Lint(parent);
310 lint.suppressedValues.add(lc);
311 lint.values.remove(lc);
312 }
313
314 public void visitConstant(Attribute.Constant value) {
315 if (value.type.tsym == syms.stringType.tsym) {
316 LintCategory lc = LintCategory.get((String) (value.value));
317 if (lc != null)
318 suppress(lc);
319 }
320 }
321
322 public void visitClass(Attribute.Class clazz) {
323 }
324
325 // If we find a @SuppressWarnings annotation, then we continue
326 // walking the tree, in order to suppress the individual warnings
327 // specified in the @SuppressWarnings annotation.
328 public void visitCompound(Attribute.Compound compound) {
329 if (compound.type.tsym == syms.suppressWarningsType.tsym) {
330 for (List<Pair<MethodSymbol,Attribute>> v = compound.values;
331 v.nonEmpty(); v = v.tail) {
332 Pair<MethodSymbol,Attribute> value = v.head;
333 if (value.fst.name.toString().equals("value"))
334 value.snd.accept(this);
335 }
336
337 }
338 }
339
340 public void visitArray(Attribute.Array array) {
341 for (Attribute value : array.values)
342 value.accept(this);
343 }
344
345 public void visitEnum(Attribute.Enum e) {
346 }
347
348 public void visitError(Attribute.Error e) {
349 }
350 }
351 }