1 /*
2 * Copyright (c) 1999, 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.Collections;
29 import java.util.EnumSet;
30 import java.util.Map;
31 import java.util.Set;
32 import java.util.concurrent.ConcurrentHashMap;
33
34 import javax.lang.model.element.Modifier;
35
36 import com.sun.tools.javac.util.Assert;
37 import com.sun.tools.javac.util.StringUtils;
38
39 /** Access flags and other modifiers for Java classes and members.
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 Flags {
47
48 private Flags() {} // uninstantiable
49
50 public static String toString(long flags) {
51 StringBuilder buf = new StringBuilder();
52 String sep = "";
53 for (Flag flag : asFlagSet(flags)) {
54 buf.append(sep);
55 buf.append(flag);
56 sep = " ";
57 }
58 return buf.toString();
59 }
60
61 public static EnumSet<Flag> asFlagSet(long flags) {
62 EnumSet<Flag> flagSet = EnumSet.noneOf(Flag.class);
63 for (Flag flag : Flag.values()) {
64 if ((flags & flag.value) != 0) {
65 flagSet.add(flag);
66 flags &= ~flag.value;
67 }
68 }
69 Assert.check(flags == 0);
70 return flagSet;
71 }
72
73 /* Standard Java flags.
74 */
75 public static final int PUBLIC = 1;
76 public static final int PRIVATE = 1<<1;
77 public static final int PROTECTED = 1<<2;
78 public static final int STATIC = 1<<3;
79 public static final int FINAL = 1<<4;
80 public static final int SYNCHRONIZED = 1<<5;
81 public static final int VOLATILE = 1<<6;
82 public static final int TRANSIENT = 1<<7;
83 public static final int NATIVE = 1<<8;
84 public static final int INTERFACE = 1<<9;
85 public static final int ABSTRACT = 1<<10;
86 public static final int STRICTFP = 1<<11;
87
88 /* Flag that marks a symbol synthetic, added in classfile v49.0. */
89 public static final int SYNTHETIC = 1<<12;
90
91 /** Flag that marks attribute interfaces, added in classfile v49.0. */
92 public static final int ANNOTATION = 1<<13;
93
94 /** An enumeration type or an enumeration constant, added in
95 * classfile v49.0. */
96 public static final int ENUM = 1<<14;
97
98 /** Added in SE8, represents constructs implicitly declared in source. */
99 public static final int MANDATED = 1<<15;
100
101 /** Marks a type as a primitive class */
102 public static final int PRIMITIVE_CLASS = 1<<16;
103
104 public static final int StandardFlags = 0x0fff;
105
106 // Because the following access flags are overloaded with other
107 // bit positions, we translate them when reading and writing class
108 // files into unique bits positions: ACC_SYNTHETIC <-> SYNTHETIC,
109 // for example.
110 public static final int ACC_SUPER = 0x0020;
111 public static final int ACC_BRIDGE = 0x0040;
112 public static final int ACC_VARARGS = 0x0080;
113 public static final int ACC_PRIMITIVE = 0x0100;
114 public static final int ACC_MODULE = 0x8000;
115
116 /*****************************************
117 * Internal compiler flags (no bits in the lower 16).
118 *****************************************/
119
120 /** Flag is set if symbol is deprecated. See also DEPRECATED_REMOVAL.
121 */
122 public static final int DEPRECATED = 1<<17;
123
124 /** Flag is set for a variable symbol if the variable's definition
125 * has an initializer part.
126 */
127 public static final int HASINIT = 1<<18;
128
129 /** Flag is set for a class symbol if it defines one or more non-empty
130 * instance initializer block(s). This is relevenat only for class symbols
131 * that originate from source types. For binary types the instance initializer
132 * blocks are "normalized" into the constructors.
133 */
134 public static final int HASINITBLOCK = 1<<18;
135
136 /** Flag is set for a method symbol if it is an empty no-arg ctor.
137 * i.e one that simply returns (jlO) or merely chains to a super's
138 * EMPTYNOARGCONSTR
139 */
140 public static final int EMPTYNOARGCONSTR = 1<<18;
141
142 /**
143 * Flag is set for a reference favoring primitive class.
144 */
145 public static final int REFERENCE_FAVORING = 1<<19;
146
147 /** Flag is set for compiler-generated anonymous method symbols
148 * that `own' an initializer block.
149 */
150 public static final int BLOCK = 1<<20;
151
152 /** Flag bit 21 is available. (used earlier to tag compiler-generated abstract methods that implement
153 * an interface method (Miranda methods)).
154 */
155
156 /** Flag is set for nested classes that do not access instance members
157 * or `this' of an outer class and therefore don't need to be passed
158 * a this$n reference. This value is currently set only for anonymous
159 * classes in superclass constructor calls.
160 * todo: use this value for optimizing away this$n parameters in
161 * other cases.
162 */
163 public static final int NOOUTERTHIS = 1<<22;
164
165 /** Flag is set for package symbols if a package has a member or
166 * directory and therefore exists.
167 */
168 public static final int EXISTS = 1<<23;
169
170 /** Flag is set for compiler-generated compound classes
171 * representing multiple variable bounds
172 */
173 public static final int COMPOUND = 1<<24;
174
175 /** Flag is set for class symbols if a class file was found for this class.
176 */
177 public static final int CLASS_SEEN = 1<<25;
178
179 /** Flag is set for class symbols if a source file was found for this
180 * class.
181 */
182 public static final int SOURCE_SEEN = 1<<26;
183
184 /* State flags (are reset during compilation).
185 */
186
187 /** Flag for class symbols is set and later re-set as a lock in
188 * Enter to detect cycles in the superclass/superinterface
189 * relations. Similarly for constructor call cycle detection in
190 * Attr.
191 */
192 public static final int LOCKED = 1<<27;
193
194 /** Flag for class symbols is set and later re-set to indicate that a class
195 * has been entered but has not yet been attributed.
196 */
197 public static final int UNATTRIBUTED = 1<<28;
198
199 /** Flag for synthesized default constructors of anonymous classes.
200 */
201 public static final int ANONCONSTR = 1<<29; //non-class members
202
203 /**
204 * Flag to indicate the super classes of this ClassSymbol has been attributed.
205 */
206 public static final int SUPER_OWNER_ATTRIBUTED = 1<<29; //ClassSymbols
207
208 /** Flag for class symbols to indicate it has been checked and found
209 * acyclic.
210 */
211 public static final int ACYCLIC = 1<<30;
212
213 /** Flag that marks bridge methods.
214 */
215 public static final long BRIDGE = 1L<<31;
216
217 /** Flag that marks formal parameters.
218 */
219 public static final long PARAMETER = 1L<<33;
220
221 /** Flag that marks varargs methods.
222 */
223 public static final long VARARGS = 1L<<34;
224
225 /** Flag for annotation type symbols to indicate it has been
226 * checked and found acyclic.
227 */
228 public static final long ACYCLIC_ANN = 1L<<35;
229
230 /** Flag that marks a generated default constructor.
231 */
232 public static final long GENERATEDCONSTR = 1L<<36;
233
234 /** Flag that marks a hypothetical method that need not really be
235 * generated in the binary, but is present in the symbol table to
236 * simplify checking for erasure clashes - also used for 292 poly sig methods.
237 */
238 public static final long HYPOTHETICAL = 1L<<37;
239
240 /**
241 * Flag that marks an internal proprietary class.
242 */
243 public static final long PROPRIETARY = 1L<<38;
244
245 /**
246 * Flag that marks a multi-catch parameter.
247 */
248 public static final long UNION = 1L<<39;
249
250 /**
251 * Flags an erroneous TypeSymbol as viable for recovery.
252 * TypeSymbols only.
253 */
254 public static final long RECOVERABLE = 1L<<40;
255
256 /**
257 * Flag that marks an 'effectively final' local variable.
258 */
259 public static final long EFFECTIVELY_FINAL = 1L<<41;
260
261 /**
262 * Flag that marks non-override equivalent methods with the same signature,
263 * or a conflicting match binding (BindingSymbol).
264 */
265 public static final long CLASH = 1L<<42;
266
267 /**
268 * Flag that marks either a default method or an interface containing default methods.
269 */
270 public static final long DEFAULT = 1L<<43;
271
272 /**
273 * Flag that marks class as auxiliary, ie a non-public class following
274 * the public class in a source file, that could block implicit compilation.
275 */
276 public static final long AUXILIARY = 1L<<44;
277
278 /**
279 * Flag that marks that a symbol is not available in the current profile
280 */
281 public static final long NOT_IN_PROFILE = 1L<<45;
282
283 /**
284 * Flag that indicates that an override error has been detected by Check.
285 */
286 public static final long BAD_OVERRIDE = 1L<<45;
287
288 /**
289 * Flag that indicates a signature polymorphic method (292).
290 */
291 public static final long SIGNATURE_POLYMORPHIC = 1L<<46;
292
293 /**
294 * Flag that indicates that an inference variable is used in a 'throws' clause.
295 */
296 public static final long THROWS = 1L<<47;
297
298 /**
299 * Flag that marks potentially ambiguous overloads
300 */
301 public static final long POTENTIALLY_AMBIGUOUS = 1L<<48;
302
303 /**
304 * Flag that marks a synthetic method body for a lambda expression
305 */
306 public static final long LAMBDA_METHOD = 1L<<49;
307
308 /**
309 * Flag to control recursion in TransTypes
310 */
311 public static final long TYPE_TRANSLATED = 1L<<50;
312
313 /**
314 * Flag to indicate class symbol is for module-info
315 */
316 public static final long MODULE = 1L<<51;
317
318 /**
319 * Flag to indicate the given ModuleSymbol is an automatic module.
320 */
321 public static final long AUTOMATIC_MODULE = 1L<<52; //ModuleSymbols only
322
323 /**
324 * Flag to indicate the given PackageSymbol contains any non-.java and non-.class resources.
325 */
326 public static final long HAS_RESOURCE = 1L<<52; //PackageSymbols only
327
328 /**
329 * Flag to indicate the given ParamSymbol has a user-friendly name filled.
330 */
331 public static final long NAME_FILLED = 1L<<52; //ParamSymbols only
332
333 /**
334 * Flag to indicate the given ModuleSymbol is a system module.
335 */
336 public static final long SYSTEM_MODULE = 1L<<53; //ModuleSymbols only
337
338 /**
339 * Flag to indicate the given ClassSymbol is a value based.
340 */
341 public static final long VALUE_BASED = 1L<<53; //ClassSymbols only
342
343 /**
344 * Flag to indicate the given symbol has a @Deprecated annotation.
345 */
346 public static final long DEPRECATED_ANNOTATION = 1L<<54;
347
348 /**
349 * Flag to indicate the given symbol has been deprecated and marked for removal.
350 */
351 public static final long DEPRECATED_REMOVAL = 1L<<55;
352
353 /**
354 * Flag to indicate the API element in question is for a preview API.
355 */
356 public static final long PREVIEW_API = 1L<<56; //any Symbol kind
357
358 /**
359 * Flag for synthesized default constructors of anonymous classes that have an enclosing expression.
360 */
361 public static final long ANONCONSTR_BASED = 1L<<57;
362
363 /**
364 * Flag that marks finalize block as body-only, should not be copied into catch clauses.
365 * Used to implement try-with-resources.
366 */
367 public static final long BODY_ONLY_FINALIZE = 1L<<17; //blocks only
368
369 /**
370 * Flag to indicate the API element in question is for a preview API.
371 */
372 public static final long PREVIEW_REFLECTIVE = 1L<<58; //any Symbol kind
373
374 /**
375 * Flag to indicate the given variable is a match binding variable.
376 */
377 public static final long MATCH_BINDING = 1L<<59;
378
379 /**
380 * A flag to indicate a match binding variable whose scope extends after the current statement.
381 */
382 public static final long MATCH_BINDING_TO_OUTER = 1L<<60;
383
384 /**
385 * Flag to indicate that a class is a record. The flag is also used to mark fields that are
386 * part of the state vector of a record and to mark the canonical constructor
387 */
388 public static final long RECORD = 1L<<61; // ClassSymbols, MethodSymbols and VarSymbols
389
390 /**
391 * Flag to mark a record constructor as a compact one
392 */
393 public static final long COMPACT_RECORD_CONSTRUCTOR = 1L<<51; // MethodSymbols only
394
395 /**
396 * Flag to mark a record field that was not initialized in the compact constructor
397 */
398 public static final long UNINITIALIZED_FIELD= 1L<<51; // VarSymbols only
399
400 /** Flag is set for compiler-generated record members, it could be applied to
401 * accessors and fields
402 */
403 public static final int GENERATED_MEMBER = 1<<24; // MethodSymbols and VarSymbols
404
405 /**
406 * Flag to indicate sealed class/interface declaration.
407 */
408 public static final long SEALED = 1L<<62; // ClassSymbols
409
410 /**
411 * Flag to indicate that the class/interface was declared with the non-sealed modifier.
412 */
413 public static final long NON_SEALED = 1L<<63; // ClassSymbols
414
415 // Encodings for extended flags stored using attributes
416 /**
417 * Flag to indicate that the primitive class is reference default.
418 */
419 public static final int ACC_REF_DEFAULT = 1;
420
421 /** Modifier masks.
422 */
423 public static final int
424 AccessFlags = PUBLIC | PROTECTED | PRIVATE,
425 LocalClassFlags = FINAL | ABSTRACT | STRICTFP | ENUM | SYNTHETIC | PRIMITIVE_CLASS,
426 StaticLocalFlags = LocalClassFlags | STATIC | INTERFACE,
427 MemberClassFlags = LocalClassFlags | INTERFACE | AccessFlags,
428 MemberStaticClassFlags = MemberClassFlags | STATIC,
429 ClassFlags = LocalClassFlags | INTERFACE | PUBLIC | ANNOTATION,
430 InterfaceVarFlags = FINAL | STATIC | PUBLIC,
431 VarFlags = AccessFlags | FINAL | STATIC |
432 VOLATILE | TRANSIENT | ENUM,
433 ConstructorFlags = AccessFlags,
434 InterfaceMethodFlags = ABSTRACT | PUBLIC,
435 MethodFlags = AccessFlags | ABSTRACT | STATIC | NATIVE |
436 SYNCHRONIZED | FINAL | STRICTFP,
437 RecordMethodFlags = AccessFlags | ABSTRACT | STATIC |
438 SYNCHRONIZED | FINAL | STRICTFP;
439 public static final long
440 ExtendedStandardFlags = (long)StandardFlags | DEFAULT | SEALED | NON_SEALED | PRIMITIVE_CLASS,
441 ExtendedMemberClassFlags = (long)MemberClassFlags | SEALED | NON_SEALED,
442 ExtendedMemberStaticClassFlags = (long) MemberStaticClassFlags | SEALED | NON_SEALED,
443 ExtendedClassFlags = (long)ClassFlags | SEALED | NON_SEALED,
444 ModifierFlags = ((long)StandardFlags & ~INTERFACE) | DEFAULT | SEALED | NON_SEALED,
445 InterfaceMethodMask = ABSTRACT | PRIVATE | STATIC | PUBLIC | STRICTFP | DEFAULT,
446 AnnotationTypeElementMask = ABSTRACT | PUBLIC,
447 LocalVarFlags = FINAL | PARAMETER,
448 ReceiverParamFlags = PARAMETER;
449
450 public static Set<Modifier> asModifierSet(long flags) {
451 Set<Modifier> modifiers = modifierSets.get(flags);
452 if (modifiers == null) {
453 modifiers = java.util.EnumSet.noneOf(Modifier.class);
454 if (0 != (flags & PUBLIC)) modifiers.add(Modifier.PUBLIC);
455 if (0 != (flags & PROTECTED)) modifiers.add(Modifier.PROTECTED);
456 if (0 != (flags & PRIVATE)) modifiers.add(Modifier.PRIVATE);
457 if (0 != (flags & ABSTRACT)) modifiers.add(Modifier.ABSTRACT);
458 if (0 != (flags & STATIC)) modifiers.add(Modifier.STATIC);
459 if (0 != (flags & SEALED)) modifiers.add(Modifier.SEALED);
460 if (0 != (flags & NON_SEALED))
461 modifiers.add(Modifier.NON_SEALED);
462 if (0 != (flags & FINAL)) modifiers.add(Modifier.FINAL);
463 if (0 != (flags & TRANSIENT)) modifiers.add(Modifier.TRANSIENT);
464 if (0 != (flags & VOLATILE)) modifiers.add(Modifier.VOLATILE);
465 if (0 != (flags & SYNCHRONIZED))
466 modifiers.add(Modifier.SYNCHRONIZED);
467 if (0 != (flags & NATIVE)) modifiers.add(Modifier.NATIVE);
468 if (0 != (flags & STRICTFP)) modifiers.add(Modifier.STRICTFP);
469 if (0 != (flags & DEFAULT)) modifiers.add(Modifier.DEFAULT);
470 if (0 != (flags & PRIMITIVE_CLASS)) modifiers.add(Modifier.PRIMITIVE);
471 modifiers = Collections.unmodifiableSet(modifiers);
472 modifierSets.put(flags, modifiers);
473 }
474 return modifiers;
475 }
476
477 // Cache of modifier sets.
478 private static final Map<Long, Set<Modifier>> modifierSets = new ConcurrentHashMap<>(64);
479
480 public static boolean isStatic(Symbol symbol) {
481 return (symbol.flags() & STATIC) != 0;
482 }
483
484 public static boolean isEnum(Symbol symbol) {
485 return (symbol.flags() & ENUM) != 0;
486 }
487
488 public static boolean isConstant(Symbol.VarSymbol symbol) {
489 return symbol.getConstValue() != null;
490 }
491
492
493 public enum Flag {
494 PUBLIC(Flags.PUBLIC),
495 PRIVATE(Flags.PRIVATE),
496 PROTECTED(Flags.PROTECTED),
497 STATIC(Flags.STATIC),
498 FINAL(Flags.FINAL),
499 SYNCHRONIZED(Flags.SYNCHRONIZED),
500 VOLATILE(Flags.VOLATILE),
501 TRANSIENT(Flags.TRANSIENT),
502 NATIVE(Flags.NATIVE),
503 INTERFACE(Flags.INTERFACE),
504 ABSTRACT(Flags.ABSTRACT),
505 DEFAULT(Flags.DEFAULT),
506 STRICTFP(Flags.STRICTFP),
507 BRIDGE(Flags.BRIDGE),
508 SYNTHETIC(Flags.SYNTHETIC),
509 ANNOTATION(Flags.ANNOTATION),
510 DEPRECATED(Flags.DEPRECATED),
511 HASINIT(Flags.HASINIT),
512 HASINITBLOCK(Flags.HASINITBLOCK),
513 EMPTYNOARGCONSTR(Flags.EMPTYNOARGCONSTR),
514 REFERENCE_FAVORING(Flags.REFERENCE_FAVORING),
515 BLOCK(Flags.BLOCK),
516 ENUM(Flags.ENUM),
517 MANDATED(Flags.MANDATED),
518 PRIMITIVE(Flags.PRIMITIVE_CLASS),
519 NOOUTERTHIS(Flags.NOOUTERTHIS),
520 EXISTS(Flags.EXISTS),
521 COMPOUND(Flags.COMPOUND),
522 CLASS_SEEN(Flags.CLASS_SEEN),
523 SOURCE_SEEN(Flags.SOURCE_SEEN),
524 LOCKED(Flags.LOCKED),
525 UNATTRIBUTED(Flags.UNATTRIBUTED),
526 ANONCONSTR(Flags.ANONCONSTR),
527 ACYCLIC(Flags.ACYCLIC),
528 PARAMETER(Flags.PARAMETER),
529 VARARGS(Flags.VARARGS),
530 ACYCLIC_ANN(Flags.ACYCLIC_ANN),
531 GENERATEDCONSTR(Flags.GENERATEDCONSTR),
532 HYPOTHETICAL(Flags.HYPOTHETICAL),
533 PROPRIETARY(Flags.PROPRIETARY),
534 UNION(Flags.UNION),
535 EFFECTIVELY_FINAL(Flags.EFFECTIVELY_FINAL),
536 CLASH(Flags.CLASH),
537 AUXILIARY(Flags.AUXILIARY),
538 NOT_IN_PROFILE(Flags.NOT_IN_PROFILE),
539 BAD_OVERRIDE(Flags.BAD_OVERRIDE),
540 SIGNATURE_POLYMORPHIC(Flags.SIGNATURE_POLYMORPHIC),
541 THROWS(Flags.THROWS),
542 LAMBDA_METHOD(Flags.LAMBDA_METHOD),
543 TYPE_TRANSLATED(Flags.TYPE_TRANSLATED),
544 MODULE(Flags.MODULE),
545 AUTOMATIC_MODULE(Flags.AUTOMATIC_MODULE),
546 SYSTEM_MODULE(Flags.SYSTEM_MODULE),
547 DEPRECATED_ANNOTATION(Flags.DEPRECATED_ANNOTATION),
548 DEPRECATED_REMOVAL(Flags.DEPRECATED_REMOVAL),
549 HAS_RESOURCE(Flags.HAS_RESOURCE),
550 POTENTIALLY_AMBIGUOUS(Flags.POTENTIALLY_AMBIGUOUS),
551 ANONCONSTR_BASED(Flags.ANONCONSTR_BASED),
552 NAME_FILLED(Flags.NAME_FILLED),
553 PREVIEW_API(Flags.PREVIEW_API),
554 PREVIEW_REFLECTIVE(Flags.PREVIEW_REFLECTIVE),
555 MATCH_BINDING(Flags.MATCH_BINDING),
556 MATCH_BINDING_TO_OUTER(Flags.MATCH_BINDING_TO_OUTER),
557 RECORD(Flags.RECORD),
558 RECOVERABLE(Flags.RECOVERABLE),
559 SEALED(Flags.SEALED),
560 NON_SEALED(Flags.NON_SEALED) {
561 @Override
562 public String toString() {
563 return "non-sealed";
564 }
565 };
566
567 Flag(long flag) {
568 this.value = flag;
569 this.lowercaseName = StringUtils.toLowerCase(name());
570 }
571
572 @Override
573 public String toString() {
574 return lowercaseName;
575 }
576
577 final long value;
578 final String lowercaseName;
579 }
580
581 }