1 /*
2 * Copyright (c) 2005, 2021, 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()) {
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 protected Lint(Context context) {
104 // initialize values according to the lint options
105 Options options = Options.instance(context);
106
107 if (options.isSet(Option.XLINT) || options.isSet(Option.XLINT_CUSTOM, "all")) {
108 // If -Xlint or -Xlint:all is given, enable all categories by default
109 values = EnumSet.allOf(LintCategory.class);
110 } else if (options.isSet(Option.XLINT_CUSTOM, "none")) {
111 // if -Xlint:none is given, disable all categories by default
112 values = EnumSet.noneOf(LintCategory.class);
113 } else {
114 // otherwise, enable on-by-default categories
115 values = EnumSet.noneOf(LintCategory.class);
116
117 Source source = Source.instance(context);
118 if (source.compareTo(Source.JDK9) >= 0) {
119 values.add(LintCategory.DEP_ANN);
120 }
121 if (Source.Feature.REDUNDANT_STRICTFP.allowedInSource(source)) {
122 values.add(LintCategory.STRICTFP);
123 }
124 values.add(LintCategory.REQUIRES_TRANSITIVE_AUTOMATIC);
125 values.add(LintCategory.OPENS);
126 values.add(LintCategory.MODULE);
127 values.add(LintCategory.REMOVAL);
128 if (!options.isSet(Option.PREVIEW)) {
129 values.add(LintCategory.PREVIEW);
130 }
131 values.add(LintCategory.SYNCHRONIZATION);
132 }
133
134 // Look for specific overrides
135 for (LintCategory lc : LintCategory.values()) {
136 if (options.isSet(Option.XLINT_CUSTOM, lc.option)) {
137 values.add(lc);
138 } else if (options.isSet(Option.XLINT_CUSTOM, "-" + lc.option)) {
139 values.remove(lc);
140 }
141 }
142
143 suppressedValues = EnumSet.noneOf(LintCategory.class);
144
145 context.put(lintKey, this);
146 augmentor = new AugmentVisitor(context);
147 }
148
149 protected Lint(Lint other) {
150 this.augmentor = other.augmentor;
151 this.values = other.values.clone();
152 this.suppressedValues = other.suppressedValues.clone();
153 }
154
155 @Override
156 public String toString() {
157 return "Lint:[values" + values + " suppressedValues" + suppressedValues + "]";
158 }
159
160 /**
161 * Categories of warnings that can be generated by the compiler.
162 */
163 public enum LintCategory {
164 /**
165 * Warn when code refers to a auxiliary class that is hidden in a source file (ie source file name is
166 * different from the class name, and the type is not properly nested) and the referring code
167 * is not located in the same source file.
168 */
169 AUXILIARYCLASS("auxiliaryclass"),
170
171 /**
172 * Warn about use of unnecessary casts.
173 */
174 CAST("cast"),
175
176 /**
177 * Warn about issues related to classfile contents
178 */
179 CLASSFILE("classfile"),
180
181 /**
182 * Warn about use of deprecated items.
183 */
184 DEPRECATION("deprecation"),
185
186 /**
187 * Warn about items which are documented with an {@code @deprecated} JavaDoc
188 * comment, but which do not have {@code @Deprecated} annotation.
189 */
190 DEP_ANN("dep-ann"),
191
192 /**
193 * Warn about division by constant integer 0.
194 */
195 DIVZERO("divzero"),
196
197 /**
198 * Warn about empty statement after if.
199 */
200 EMPTY("empty"),
201
202 /**
203 * Warn about issues regarding module exports.
204 */
205 EXPORTS("exports"),
206
207 /**
208 * Warn about falling through from one case of a switch statement to the next.
209 */
210 FALLTHROUGH("fallthrough"),
211
212 /**
213 * Warn about finally clauses that do not terminate normally.
214 */
215 FINALLY("finally"),
216
217 /**
218 * Warn about compiler generation of a default constructor.
219 */
220 MISSING_EXPLICIT_CTOR("missing-explicit-ctor"),
221
222 /**
223 * Warn about module system related issues.
224 */
225 MODULE("module"),
226
227 /**
228 * Warn about issues regarding module opens.
229 */
230 OPENS("opens"),
231
232 /**
233 * Warn about issues relating to use of command line options
234 */
235 OPTIONS("options"),
236
237 /**
238 * Warn about issues regarding method overloads.
239 */
240 OVERLOADS("overloads"),
241
242 /**
243 * Warn about issues regarding method overrides.
244 */
245 OVERRIDES("overrides"),
246
247 /**
248 * Warn about invalid path elements on the command line.
249 * Such warnings cannot be suppressed with the SuppressWarnings
250 * annotation.
251 */
252 PATH("path"),
253
254 /**
255 * Warn about issues regarding annotation processing.
256 */
257 PROCESSING("processing"),
258
259 /**
260 * Warn about unchecked operations on raw types.
261 */
262 RAW("rawtypes"),
263
264 /**
265 * Warn about use of deprecated-for-removal items.
266 */
267 REMOVAL("removal"),
268
269 /**
270 * Warn about use of automatic modules in the requires clauses.
271 */
272 REQUIRES_AUTOMATIC("requires-automatic"),
273
274 /**
275 * Warn about automatic modules in requires transitive.
276 */
277 REQUIRES_TRANSITIVE_AUTOMATIC("requires-transitive-automatic"),
278
279 /**
280 * Warn about Serializable classes that do not provide a serial version ID.
281 */
282 SERIAL("serial"),
283
284 /**
285 * Warn about issues relating to use of statics
286 */
287 STATIC("static"),
288
289 /**
290 * Warn about unnecessary uses of the strictfp modifier
291 */
292 STRICTFP("strictfp"),
293
294 /**
295 * Warn about synchronization attempts on instances of @ValueBased classes.
296 */
297 SYNCHRONIZATION("synchronization"),
298
299 /**
300 * Warn about issues relating to use of text blocks
301 */
302 TEXT_BLOCKS("text-blocks"),
303
304 /**
305 * Warn about issues relating to use of try blocks (i.e. try-with-resources)
306 */
307 TRY("try"),
308
309 /**
310 * Warn about unchecked operations on raw types.
311 */
312 UNCHECKED("unchecked"),
313
314 /**
315 * Warn about potentially unsafe vararg methods
316 */
317 VARARGS("varargs"),
318
319 /**
320 * Warn about use of preview features.
321 */
322 PREVIEW("preview");
323
324 LintCategory(String option) {
325 this(option, false);
326 }
327
328 LintCategory(String option, boolean hidden) {
329 this.option = option;
330 this.hidden = hidden;
331 map.put(option, this);
332 }
333
334 static LintCategory get(String option) {
335 return map.get(option);
336 }
337
338 public final String option;
339 public final boolean hidden;
340 }
341
342 /**
343 * Checks if a warning category is enabled. A warning category may be enabled
344 * on the command line, or by default, and can be temporarily disabled with
345 * the SuppressWarnings annotation.
346 */
347 public boolean isEnabled(LintCategory lc) {
348 return values.contains(lc);
349 }
350
351 /**
352 * Checks is a warning category has been specifically suppressed, by means
353 * of the SuppressWarnings annotation, or, in the case of the deprecated
354 * category, whether it has been implicitly suppressed by virtue of the
355 * current entity being itself deprecated.
356 */
357 public boolean isSuppressed(LintCategory lc) {
358 return suppressedValues.contains(lc);
359 }
360
361 protected static class AugmentVisitor implements Attribute.Visitor {
362 private final Context context;
363 private Symtab syms;
364 private Lint parent;
365 private Lint lint;
366
367 AugmentVisitor(Context context) {
368 // to break an ugly sequence of initialization dependencies,
369 // we defer the initialization of syms until it is needed
370 this.context = context;
371 }
372
373 Lint augment(Lint parent, Attribute.Compound attr) {
374 initSyms();
375 this.parent = parent;
376 lint = null;
377 attr.accept(this);
378 return (lint == null ? parent : lint);
379 }
380
381 Lint augment(Lint parent, List<Attribute.Compound> attrs) {
382 initSyms();
383 this.parent = parent;
384 lint = null;
385 for (Attribute.Compound a: attrs) {
386 a.accept(this);
387 }
388 return (lint == null ? parent : lint);
389 }
390
391 private void initSyms() {
392 if (syms == null)
393 syms = Symtab.instance(context);
394 }
395
396 private void suppress(LintCategory lc) {
397 if (lint == null)
398 lint = new Lint(parent);
399 lint.suppressedValues.add(lc);
400 lint.values.remove(lc);
401 }
402
403 public void visitConstant(Attribute.Constant value) {
404 if (value.type.tsym == syms.stringType.tsym) {
405 LintCategory lc = LintCategory.get((String) (value.value));
406 if (lc != null)
407 suppress(lc);
408 }
409 }
410
411 public void visitClass(Attribute.Class clazz) {
412 }
413
414 // If we find a @SuppressWarnings annotation, then we continue
415 // walking the tree, in order to suppress the individual warnings
416 // specified in the @SuppressWarnings annotation.
417 public void visitCompound(Attribute.Compound compound) {
418 if (compound.type.tsym == syms.suppressWarningsType.tsym) {
419 for (List<Pair<MethodSymbol,Attribute>> v = compound.values;
420 v.nonEmpty(); v = v.tail) {
421 Pair<MethodSymbol,Attribute> value = v.head;
422 if (value.fst.name.toString().equals("value"))
423 value.snd.accept(this);
424 }
425
426 }
427 }
428
429 public void visitArray(Attribute.Array array) {
430 for (Attribute value : array.values)
431 value.accept(this);
432 }
433
434 public void visitEnum(Attribute.Enum e) {
435 }
436
437 public void visitError(Attribute.Error e) {
438 }
439 }
440 }