1 /*
2 * Copyright (c) 2005, 2024, 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.Arrays;
29 import java.util.EnumSet;
30 import java.util.Map;
31 import java.util.concurrent.ConcurrentHashMap;
32
33 import com.sun.tools.javac.code.Symbol.*;
34 import com.sun.tools.javac.main.Option;
35 import com.sun.tools.javac.util.Context;
36 import com.sun.tools.javac.util.List;
37 import com.sun.tools.javac.util.Options;
38 import com.sun.tools.javac.util.Pair;
39
40 /**
41 * A class for handling -Xlint suboptions and @SuppressWarnings.
42 *
43 * <p><b>This is NOT part of any supported API.
44 * If you write code that depends on this, you do so at your own risk.
45 * This code and its internal interfaces are subject to change or
46 * deletion without notice.</b>
47 */
48 public class Lint
49 {
50 /** The context key for the root Lint object. */
51 protected static final Context.Key<Lint> lintKey = new Context.Key<>();
52
53 /** Get the root Lint instance. */
54 public static Lint instance(Context context) {
55 Lint instance = context.get(lintKey);
56 if (instance == null)
57 instance = new Lint(context);
58 return instance;
59 }
60
61 /**
62 * Returns the result of combining the values in this object with
63 * the given annotation.
64 */
65 public Lint augment(Attribute.Compound attr) {
66 return augmentor.augment(this, attr);
67 }
68
69
70 /**
71 * Returns the result of combining the values in this object with
72 * the metadata on the given symbol.
73 */
74 public Lint augment(Symbol sym) {
75 Lint l = augmentor.augment(this, sym.getDeclarationAttributes());
76 if (sym.isDeprecated() && sym.isDeprecatableViaAnnotation()) {
77 if (l == this)
78 l = new Lint(this);
79 l.values.remove(LintCategory.DEPRECATION);
80 l.suppressedValues.add(LintCategory.DEPRECATION);
81 }
82 return l;
83 }
84
85 /**
86 * Returns a new Lint that has the given LintCategorys suppressed.
87 * @param lc one or more categories to be suppressed
88 */
89 public Lint suppress(LintCategory... lc) {
90 Lint l = new Lint(this);
91 l.values.removeAll(Arrays.asList(lc));
92 l.suppressedValues.addAll(Arrays.asList(lc));
93 return l;
94 }
95
96 private final AugmentVisitor augmentor;
97
98 private final EnumSet<LintCategory> values;
99 private final EnumSet<LintCategory> suppressedValues;
100
101 private static final Map<String, LintCategory> map = new ConcurrentHashMap<>(20);
102
103 @SuppressWarnings("this-escape")
104 protected Lint(Context context) {
105 // initialize values according to the lint options
106 Options options = Options.instance(context);
107
108 if (options.isSet(Option.XLINT) || options.isSet(Option.XLINT_CUSTOM, "all")) {
109 // If -Xlint or -Xlint:all is given, enable all categories by default
110 values = EnumSet.allOf(LintCategory.class);
111 } else if (options.isSet(Option.XLINT_CUSTOM, "none")) {
112 // if -Xlint:none is given, disable all categories by default
113 values = EnumSet.noneOf(LintCategory.class);
114 } else {
115 // otherwise, enable on-by-default categories
116 values = EnumSet.noneOf(LintCategory.class);
117
118 Source source = Source.instance(context);
119 if (source.compareTo(Source.JDK9) >= 0) {
120 values.add(LintCategory.DEP_ANN);
121 }
122 if (Source.Feature.REDUNDANT_STRICTFP.allowedInSource(source)) {
123 values.add(LintCategory.STRICTFP);
124 }
125 values.add(LintCategory.REQUIRES_TRANSITIVE_AUTOMATIC);
126 values.add(LintCategory.OPENS);
127 values.add(LintCategory.MODULE);
128 values.add(LintCategory.REMOVAL);
129 if (!options.isSet(Option.PREVIEW)) {
130 values.add(LintCategory.PREVIEW);
131 }
132 values.add(LintCategory.SYNCHRONIZATION);
133 values.add(LintCategory.INCUBATING);
134 }
135
136 // Look for specific overrides
137 for (LintCategory lc : LintCategory.values()) {
138 if (options.isSet(Option.XLINT_CUSTOM, lc.option)) {
139 values.add(lc);
140 } else if (options.isSet(Option.XLINT_CUSTOM, "-" + lc.option)) {
141 values.remove(lc);
142 }
143 }
144
145 suppressedValues = EnumSet.noneOf(LintCategory.class);
146
147 context.put(lintKey, this);
148 augmentor = new AugmentVisitor(context);
149 }
150
151 protected Lint(Lint other) {
152 this.augmentor = other.augmentor;
153 this.values = other.values.clone();
154 this.suppressedValues = other.suppressedValues.clone();
155 }
156
157 @Override
158 public String toString() {
159 return "Lint:[values" + values + " suppressedValues" + suppressedValues + "]";
160 }
161
162 /**
163 * Categories of warnings that can be generated by the compiler.
164 */
165 public enum LintCategory {
166 /**
167 * Warn when code refers to a auxiliary class that is hidden in a source file (ie source file name is
168 * different from the class name, and the type is not properly nested) and the referring code
169 * is not located in the same source file.
170 */
171 AUXILIARYCLASS("auxiliaryclass"),
172
173 /**
174 * Warn about use of unnecessary casts.
175 */
176 CAST("cast"),
177
178 /**
179 * Warn about issues related to classfile contents
180 */
181 CLASSFILE("classfile"),
182
183 /**
184 * Warn about"dangling" documentation comments,
185 * not attached to any declaration.
186 */
187 DANGLING_DOC_COMMENTS("dangling-doc-comments"),
188
189 /**
190 * Warn about use of deprecated items.
191 */
192 DEPRECATION("deprecation"),
193
194 /**
195 * Warn about items which are documented with an {@code @deprecated} JavaDoc
196 * comment, but which do not have {@code @Deprecated} annotation.
197 */
198 DEP_ANN("dep-ann"),
199
200 /**
201 * Warn about division by constant integer 0.
202 */
203 DIVZERO("divzero"),
204
205 /**
206 * Warn about empty statement after if.
207 */
208 EMPTY("empty"),
209
210 /**
211 * Warn about issues regarding module exports.
212 */
213 EXPORTS("exports"),
214
215 /**
216 * Warn about falling through from one case of a switch statement to the next.
217 */
218 FALLTHROUGH("fallthrough"),
219
220 /**
221 * Warn about finally clauses that do not terminate normally.
222 */
223 FINALLY("finally"),
224
225 /**
226 * Warn about use of incubating modules.
227 */
228 INCUBATING("incubating"),
229
230 /**
231 * Warn about compiler possible lossy conversions.
232 */
233 LOSSY_CONVERSIONS("lossy-conversions"),
234
235 /**
236 * Warn about compiler generation of a default constructor.
237 */
238 MISSING_EXPLICIT_CTOR("missing-explicit-ctor"),
239
240 /**
241 * Warn about module system related issues.
242 */
243 MODULE("module"),
244
245 /**
246 * Warn about issues related to migration of JDK classes.
247 */
248 MIGRATION("migration"),
249
250 /**
251 * Warn about issues regarding module opens.
252 */
253 OPENS("opens"),
254
255 /**
256 * Warn about issues relating to use of command line options
257 */
258 OPTIONS("options"),
259
260 /**
261 * Warn when any output file is written to more than once.
262 */
263 OUTPUT_FILE_CLASH("output-file-clash"),
264
265 /**
266 * Warn about issues regarding method overloads.
267 */
268 OVERLOADS("overloads"),
269
270 /**
271 * Warn about issues regarding method overrides.
272 */
273 OVERRIDES("overrides"),
274
275 /**
276 * Warn about invalid path elements on the command line.
277 * Such warnings cannot be suppressed with the SuppressWarnings
278 * annotation.
279 */
280 PATH("path"),
281
282 /**
283 * Warn about issues regarding annotation processing.
284 */
285 PROCESSING("processing"),
286
287 /**
288 * Warn about unchecked operations on raw types.
289 */
290 RAW("rawtypes"),
291
292 /**
293 * Warn about use of deprecated-for-removal items.
294 */
295 REMOVAL("removal"),
296
297 /**
298 * Warn about use of automatic modules in the requires clauses.
299 */
300 REQUIRES_AUTOMATIC("requires-automatic"),
301
302 /**
303 * Warn about automatic modules in requires transitive.
304 */
305 REQUIRES_TRANSITIVE_AUTOMATIC("requires-transitive-automatic"),
306
307 /**
308 * Warn about Serializable classes that do not provide a serial version ID.
309 */
310 SERIAL("serial"),
311
312 /**
313 * Warn about issues relating to use of statics
314 */
315 STATIC("static"),
316
317 /**
318 * Warn about unnecessary uses of the strictfp modifier
319 */
320 STRICTFP("strictfp"),
321
322 /**
323 * Warn about synchronization attempts on instances of @ValueBased classes.
324 */
325 SYNCHRONIZATION("synchronization"),
326
327 /**
328 * Warn about issues relating to use of text blocks
329 */
330 TEXT_BLOCKS("text-blocks"),
331
332 /**
333 * Warn about possible 'this' escapes before subclass instance is fully initialized.
334 */
335 THIS_ESCAPE("this-escape"),
336
337 /**
338 * Warn about issues relating to use of try blocks (i.e. try-with-resources)
339 */
340 TRY("try"),
341
342 /**
343 * Warn about unchecked operations on raw types.
344 */
345 UNCHECKED("unchecked"),
346
347 /**
348 * Warn about potentially unsafe vararg methods
349 */
350 VARARGS("varargs"),
351
352 /**
353 * Warn about use of preview features.
354 */
355 PREVIEW("preview"),
356
357 /**
358 * Warn about use of restricted methods.
359 */
360 RESTRICTED("restricted");
361
362 LintCategory(String option) {
363 this.option = option;
364 map.put(option, this);
365 }
366
367 static LintCategory get(String option) {
368 return map.get(option);
369 }
370
371 public final String option;
372 }
373
374 /**
375 * Checks if a warning category is enabled. A warning category may be enabled
376 * on the command line, or by default, and can be temporarily disabled with
377 * the SuppressWarnings annotation.
378 */
379 public boolean isEnabled(LintCategory lc) {
380 return values.contains(lc);
381 }
382
383 /**
384 * Checks is a warning category has been specifically suppressed, by means
385 * of the SuppressWarnings annotation, or, in the case of the deprecated
386 * category, whether it has been implicitly suppressed by virtue of the
387 * current entity being itself deprecated.
388 */
389 public boolean isSuppressed(LintCategory lc) {
390 return suppressedValues.contains(lc);
391 }
392
393 protected static class AugmentVisitor implements Attribute.Visitor {
394 private final Context context;
395 private Symtab syms;
396 private Lint parent;
397 private Lint lint;
398
399 AugmentVisitor(Context context) {
400 // to break an ugly sequence of initialization dependencies,
401 // we defer the initialization of syms until it is needed
402 this.context = context;
403 }
404
405 Lint augment(Lint parent, Attribute.Compound attr) {
406 initSyms();
407 this.parent = parent;
408 lint = null;
409 attr.accept(this);
410 return (lint == null ? parent : lint);
411 }
412
413 Lint augment(Lint parent, List<Attribute.Compound> attrs) {
414 initSyms();
415 this.parent = parent;
416 lint = null;
417 for (Attribute.Compound a: attrs) {
418 a.accept(this);
419 }
420 return (lint == null ? parent : lint);
421 }
422
423 private void initSyms() {
424 if (syms == null)
425 syms = Symtab.instance(context);
426 }
427
428 private void suppress(LintCategory lc) {
429 if (lint == null)
430 lint = new Lint(parent);
431 lint.suppressedValues.add(lc);
432 lint.values.remove(lc);
433 }
434
435 public void visitConstant(Attribute.Constant value) {
436 if (value.type.tsym == syms.stringType.tsym) {
437 LintCategory lc = LintCategory.get((String) (value.value));
438 if (lc != null)
439 suppress(lc);
440 }
441 }
442
443 public void visitClass(Attribute.Class clazz) {
444 }
445
446 // If we find a @SuppressWarnings annotation, then we continue
447 // walking the tree, in order to suppress the individual warnings
448 // specified in the @SuppressWarnings annotation.
449 public void visitCompound(Attribute.Compound compound) {
450 if (compound.type.tsym == syms.suppressWarningsType.tsym) {
451 for (List<Pair<MethodSymbol,Attribute>> v = compound.values;
452 v.nonEmpty(); v = v.tail) {
453 Pair<MethodSymbol,Attribute> value = v.head;
454 if (value.fst.name.toString().equals("value"))
455 value.snd.accept(this);
456 }
457
458 }
459 }
460
461 public void visitArray(Attribute.Array array) {
462 for (Attribute value : array.values)
463 value.accept(this);
464 }
465
466 public void visitEnum(Attribute.Enum e) {
467 }
468
469 public void visitError(Attribute.Error e) {
470 }
471 }
472 }