1 /*
2 * Copyright (c) 2005, 2023, 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 use of deprecated items.
185 */
186 DEPRECATION("deprecation"),
187
188 /**
189 * Warn about items which are documented with an {@code @deprecated} JavaDoc
190 * comment, but which do not have {@code @Deprecated} annotation.
191 */
192 DEP_ANN("dep-ann"),
193
194 /**
195 * Warn about division by constant integer 0.
196 */
197 DIVZERO("divzero"),
198
199 /**
200 * Warn about empty statement after if.
201 */
202 EMPTY("empty"),
203
204 /**
205 * Warn about issues regarding module exports.
206 */
207 EXPORTS("exports"),
208
209 /**
210 * Warn about falling through from one case of a switch statement to the next.
211 */
212 FALLTHROUGH("fallthrough"),
213
214 /**
215 * Warn about finally clauses that do not terminate normally.
216 */
217 FINALLY("finally"),
218
219 /**
220 * Warn about use of incubating modules.
221 */
222 INCUBATING("incubating"),
223
224 /**
225 * Warn about compiler possible lossy conversions.
226 */
227 LOSSY_CONVERSIONS("lossy-conversions"),
228
229 /**
230 * Warn about compiler generation of a default constructor.
231 */
232 MISSING_EXPLICIT_CTOR("missing-explicit-ctor"),
233
234 /**
235 * Warn about module system related issues.
236 */
237 MODULE("module"),
238
239 /**
240 * Warn about issues regarding module opens.
241 */
242 OPENS("opens"),
243
244 /**
245 * Warn about issues relating to use of command line options
246 */
247 OPTIONS("options"),
248
249 /**
250 * Warn when any output file is written to more than once.
251 */
252 OUTPUT_FILE_CLASH("output-file-clash"),
253
254 /**
255 * Warn about issues regarding method overloads.
256 */
257 OVERLOADS("overloads"),
258
259 /**
260 * Warn about issues regarding method overrides.
261 */
262 OVERRIDES("overrides"),
263
264 /**
265 * Warn about invalid path elements on the command line.
266 * Such warnings cannot be suppressed with the SuppressWarnings
267 * annotation.
268 */
269 PATH("path"),
270
271 /**
272 * Warn about issues regarding annotation processing.
273 */
274 PROCESSING("processing"),
275
276 /**
277 * Warn about unchecked operations on raw types.
278 */
279 RAW("rawtypes"),
280
281 /**
282 * Warn about use of deprecated-for-removal items.
283 */
284 REMOVAL("removal"),
285
286 /**
287 * Warn about use of automatic modules in the requires clauses.
288 */
289 REQUIRES_AUTOMATIC("requires-automatic"),
290
291 /**
292 * Warn about automatic modules in requires transitive.
293 */
294 REQUIRES_TRANSITIVE_AUTOMATIC("requires-transitive-automatic"),
295
296 /**
297 * Warn about Serializable classes that do not provide a serial version ID.
298 */
299 SERIAL("serial"),
300
301 /**
302 * Warn about issues relating to use of statics
303 */
304 STATIC("static"),
305
306 /**
307 * Warn about unnecessary uses of the strictfp modifier
308 */
309 STRICTFP("strictfp"),
310
311 /**
312 * Warn about synchronization attempts on instances of @ValueBased classes.
313 */
314 SYNCHRONIZATION("synchronization"),
315
316 /**
317 * Warn about issues relating to use of text blocks
318 */
319 TEXT_BLOCKS("text-blocks"),
320
321 /**
322 * Warn about possible 'this' escapes before subclass instance is fully initialized.
323 */
324 THIS_ESCAPE("this-escape"),
325
326 /**
327 * Warn about issues relating to use of try blocks (i.e. try-with-resources)
328 */
329 TRY("try"),
330
331 /**
332 * Warn about unchecked operations on raw types.
333 */
334 UNCHECKED("unchecked"),
335
336 /**
337 * Warn about potentially unsafe vararg methods
338 */
339 VARARGS("varargs"),
340
341 /**
342 * Warn about use of preview features.
343 */
344 PREVIEW("preview"),
345
346 /**
347 * Warn about use of restricted methods.
348 */
349 RESTRICTED("restricted");
350
351 LintCategory(String option) {
352 this.option = option;
353 map.put(option, this);
354 }
355
356 static LintCategory get(String option) {
357 return map.get(option);
358 }
359
360 public final String option;
361 }
362
363 /**
364 * Checks if a warning category is enabled. A warning category may be enabled
365 * on the command line, or by default, and can be temporarily disabled with
366 * the SuppressWarnings annotation.
367 */
368 public boolean isEnabled(LintCategory lc) {
369 return values.contains(lc);
370 }
371
372 /**
373 * Checks is a warning category has been specifically suppressed, by means
374 * of the SuppressWarnings annotation, or, in the case of the deprecated
375 * category, whether it has been implicitly suppressed by virtue of the
376 * current entity being itself deprecated.
377 */
378 public boolean isSuppressed(LintCategory lc) {
379 return suppressedValues.contains(lc);
380 }
381
382 protected static class AugmentVisitor implements Attribute.Visitor {
383 private final Context context;
384 private Symtab syms;
385 private Lint parent;
386 private Lint lint;
387
388 AugmentVisitor(Context context) {
389 // to break an ugly sequence of initialization dependencies,
390 // we defer the initialization of syms until it is needed
391 this.context = context;
392 }
393
394 Lint augment(Lint parent, Attribute.Compound attr) {
395 initSyms();
396 this.parent = parent;
397 lint = null;
398 attr.accept(this);
399 return (lint == null ? parent : lint);
400 }
401
402 Lint augment(Lint parent, List<Attribute.Compound> attrs) {
403 initSyms();
404 this.parent = parent;
405 lint = null;
406 for (Attribute.Compound a: attrs) {
407 a.accept(this);
408 }
409 return (lint == null ? parent : lint);
410 }
411
412 private void initSyms() {
413 if (syms == null)
414 syms = Symtab.instance(context);
415 }
416
417 private void suppress(LintCategory lc) {
418 if (lint == null)
419 lint = new Lint(parent);
420 lint.suppressedValues.add(lc);
421 lint.values.remove(lc);
422 }
423
424 public void visitConstant(Attribute.Constant value) {
425 if (value.type.tsym == syms.stringType.tsym) {
426 LintCategory lc = LintCategory.get((String) (value.value));
427 if (lc != null)
428 suppress(lc);
429 }
430 }
431
432 public void visitClass(Attribute.Class clazz) {
433 }
434
435 // If we find a @SuppressWarnings annotation, then we continue
436 // walking the tree, in order to suppress the individual warnings
437 // specified in the @SuppressWarnings annotation.
438 public void visitCompound(Attribute.Compound compound) {
439 if (compound.type.tsym == syms.suppressWarningsType.tsym) {
440 for (List<Pair<MethodSymbol,Attribute>> v = compound.values;
441 v.nonEmpty(); v = v.tail) {
442 Pair<MethodSymbol,Attribute> value = v.head;
443 if (value.fst.name.toString().equals("value"))
444 value.snd.accept(this);
445 }
446
447 }
448 }
449
450 public void visitArray(Attribute.Array array) {
451 for (Attribute value : array.values)
452 value.accept(this);
453 }
454
455 public void visitEnum(Attribute.Enum e) {
456 }
457
458 public void visitError(Attribute.Error e) {
459 }
460 }
461 }