1 /*
2 * Copyright (c) 1999, 2019, 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 public static final int StandardFlags = 0x0fff;
102
103 // Because the following access flags are overloaded with other
104 // bit positions, we translate them when reading and writing class
105 // files into unique bits positions: ACC_SYNTHETIC <-> SYNTHETIC,
106 // for example.
107 public static final int ACC_SUPER = 0x0020;
108 public static final int ACC_BRIDGE = 0x0040;
109 public static final int ACC_VARARGS = 0x0080;
110 public static final int ACC_MODULE = 0x8000;
111
112 /*****************************************
113 * Internal compiler flags (no bits in the lower 16).
114 *****************************************/
115
116 /** Flag is set if symbol is deprecated. See also DEPRECATED_REMOVAL.
117 */
118 public static final int DEPRECATED = 1<<17;
119
120 /** Flag is set for a variable symbol if the variable's definition
121 * has an initializer part.
122 */
123 public static final int HASINIT = 1<<18;
124
125 /** Flag is set for compiler-generated anonymous method symbols
126 * that `own' an initializer block.
127 */
128 public static final int BLOCK = 1<<20;
129
130 /** Flag bit 21 is available. (used earlier to tag compiler-generated abstract methods that implement
131 * an interface method (Miranda methods)).
132 */
133
134 /** Flag is set for nested classes that do not access instance members
135 * or `this' of an outer class and therefore don't need to be passed
136 * a this$n reference. This value is currently set only for anonymous
137 * classes in superclass constructor calls.
138 * todo: use this value for optimizing away this$n parameters in
139 * other cases.
140 */
141 public static final int NOOUTERTHIS = 1<<22;
142
143 /** Flag is set for package symbols if a package has a member or
144 * directory and therefore exists.
145 */
146 public static final int EXISTS = 1<<23;
147
148 /** Flag is set for compiler-generated compound classes
149 * representing multiple variable bounds
150 */
151 public static final int COMPOUND = 1<<24;
152
153 /** Flag is set for class symbols if a class file was found for this class.
154 */
155 public static final int CLASS_SEEN = 1<<25;
156
157 /** Flag is set for class symbols if a source file was found for this
158 * class.
159 */
160 public static final int SOURCE_SEEN = 1<<26;
161
162 /* State flags (are reset during compilation).
163 */
164
165 /** Flag for class symbols is set and later re-set as a lock in
166 * Enter to detect cycles in the superclass/superinterface
167 * relations. Similarly for constructor call cycle detection in
168 * Attr.
169 */
170 public static final int LOCKED = 1<<27;
171
172 /** Flag for class symbols is set and later re-set to indicate that a class
173 * has been entered but has not yet been attributed.
174 */
175 public static final int UNATTRIBUTED = 1<<28;
176
177 /** Flag for synthesized default constructors of anonymous classes.
178 */
179 public static final int ANONCONSTR = 1<<29;
180
181 /** Flag for class symbols to indicate it has been checked and found
182 * acyclic.
183 */
184 public static final int ACYCLIC = 1<<30;
185
186 /** Flag that marks bridge methods.
187 */
188 public static final long BRIDGE = 1L<<31;
189
190 /** Flag that marks formal parameters.
191 */
192 public static final long PARAMETER = 1L<<33;
193
194 /** Flag that marks varargs methods.
195 */
196 public static final long VARARGS = 1L<<34;
197
198 /** Flag for annotation type symbols to indicate it has been
199 * checked and found acyclic.
200 */
201 public static final long ACYCLIC_ANN = 1L<<35;
202
203 /** Flag that marks a generated default constructor.
204 */
205 public static final long GENERATEDCONSTR = 1L<<36;
206
207 /** Flag that marks a hypothetical method that need not really be
208 * generated in the binary, but is present in the symbol table to
209 * simplify checking for erasure clashes - also used for 292 poly sig methods.
210 */
211 public static final long HYPOTHETICAL = 1L<<37;
212
213 /**
214 * Flag that marks an internal proprietary class.
215 */
216 public static final long PROPRIETARY = 1L<<38;
217
218 /**
219 * Flag that marks a multi-catch parameter.
220 */
221 public static final long UNION = 1L<<39;
222
223 // Flag bit (1L << 40) is available.
224
225 /**
226 * Flag that marks an 'effectively final' local variable.
227 */
228 public static final long EFFECTIVELY_FINAL = 1L<<41;
229
230 /**
231 * Flag that marks non-override equivalent methods with the same signature.
232 */
233 public static final long CLASH = 1L<<42;
234
235 /**
236 * Flag that marks either a default method or an interface containing default methods.
237 */
238 public static final long DEFAULT = 1L<<43;
239
240 /**
241 * Flag that marks class as auxiliary, ie a non-public class following
242 * the public class in a source file, that could block implicit compilation.
243 */
244 public static final long AUXILIARY = 1L<<44;
245
246 /**
247 * Flag that marks that a symbol is not available in the current profile
248 */
249 public static final long NOT_IN_PROFILE = 1L<<45;
250
251 /**
252 * Flag that indicates that an override error has been detected by Check.
253 */
254 public static final long BAD_OVERRIDE = 1L<<45;
255
256 /**
257 * Flag that indicates a signature polymorphic method (292).
258 */
259 public static final long SIGNATURE_POLYMORPHIC = 1L<<46;
260
261 /**
262 * Flag that indicates that an inference variable is used in a 'throws' clause.
263 */
264 public static final long THROWS = 1L<<47;
265
266 /**
267 * Flag that marks potentially ambiguous overloads
268 */
269 public static final long POTENTIALLY_AMBIGUOUS = 1L<<48;
270
271 /**
272 * Flag that marks a synthetic method body for a lambda expression
273 */
274 public static final long LAMBDA_METHOD = 1L<<49;
275
276 /**
277 * Flag to control recursion in TransTypes
278 */
279 public static final long TYPE_TRANSLATED = 1L<<50;
280
281 /**
282 * Flag to indicate class symbol is for module-info
283 */
284 public static final long MODULE = 1L<<51;
285
286 /**
287 * Flag to indicate the given ModuleSymbol is an automatic module.
288 */
289 public static final long AUTOMATIC_MODULE = 1L<<52; //ModuleSymbols only
290
291 /**
292 * Flag to indicate the given PackageSymbol contains any non-.java and non-.class resources.
293 */
294 public static final long HAS_RESOURCE = 1L<<52; //PackageSymbols only
295
296 /**
297 * Flag to indicate the given ParamSymbol has a user-friendly name filled.
298 */
299 public static final long NAME_FILLED = 1L<<52; //ParamSymbols only
300
301 /**
302 * Flag to indicate the given ModuleSymbol is a system module.
303 */
304 public static final long SYSTEM_MODULE = 1L<<53;
305
306 /**
307 * Flag to indicate the given symbol has a @Deprecated annotation.
308 */
309 public static final long DEPRECATED_ANNOTATION = 1L<<54;
310
311 /**
312 * Flag to indicate the given symbol has been deprecated and marked for removal.
313 */
314 public static final long DEPRECATED_REMOVAL = 1L<<55;
315
316 /**
317 * Flag to indicate the API element in question is for a preview API.
318 */
319 public static final long PREVIEW_API = 1L<<56; //any Symbol kind
320
321 /**
322 * Flag for synthesized default constructors of anonymous classes that have an enclosing expression.
323 */
324 public static final long ANONCONSTR_BASED = 1L<<57;
325
326 /**
327 * Flag that marks finalize block as body-only, should not be copied into catch clauses.
328 * Used to implement try-with-resources.
329 */
330 public static final long BODY_ONLY_FINALIZE = 1L<<17; //blocks only
331
332 /**
333 * Flag to indicate the API element in question is for a preview API.
334 */
335 public static final long PREVIEW_ESSENTIAL_API = 1L<<58; //any Symbol kind
336
337 /**
338 * Flag to indicate the given variable is a match binding variable.
339 */
340 public static final long MATCH_BINDING = 1L<<59;
341
342 /**
343 * A flag to indicate a match binding variable whose scope extends after the current statement.
344 */
345 public static final long MATCH_BINDING_TO_OUTER = 1L<<60;
346
347 /**
348 * Flag to indicate that a class is a record. The flag is also used to mark fields that are
349 * part of the state vector of a record and to mark the canonical constructor
350 */
351 public static final long RECORD = 1L<<61; // ClassSymbols, MethodSymbols and VarSymbols
352
353 /**
354 * Flag to mark a record constructor as a compact one
355 */
356 public static final long COMPACT_RECORD_CONSTRUCTOR = 1L<<51; // MethodSymbols only
357
358 /**
359 * Flag to mark a record field that was not initialized in the compact constructor
360 */
361 public static final long UNINITIALIZED_FIELD= 1L<<51; // VarSymbols only
362
363 /** Flag is set for compiler-generated record members, it could be applied to
364 * accessors and fields
365 */
366 public static final int GENERATED_MEMBER = 1<<24; // MethodSymbols and VarSymbols
367
368 /** Modifier masks.
369 */
370 public static final int
371 AccessFlags = PUBLIC | PROTECTED | PRIVATE,
372 LocalClassFlags = FINAL | ABSTRACT | STRICTFP | ENUM | SYNTHETIC,
373 LocalRecordFlags = LocalClassFlags | STATIC,
374 MemberClassFlags = LocalClassFlags | INTERFACE | AccessFlags,
375 MemberRecordFlags = MemberClassFlags | STATIC,
376 ClassFlags = LocalClassFlags | INTERFACE | PUBLIC | ANNOTATION,
377 InterfaceVarFlags = FINAL | STATIC | PUBLIC,
378 VarFlags = AccessFlags | FINAL | STATIC |
379 VOLATILE | TRANSIENT | ENUM,
380 ConstructorFlags = AccessFlags,
381 InterfaceMethodFlags = ABSTRACT | PUBLIC,
382 MethodFlags = AccessFlags | ABSTRACT | STATIC | NATIVE |
383 SYNCHRONIZED | FINAL | STRICTFP,
384 RecordMethodFlags = AccessFlags | ABSTRACT | STATIC |
385 SYNCHRONIZED | FINAL | STRICTFP;
386 public static final long
387 ExtendedStandardFlags = (long)StandardFlags | DEFAULT,
388 ModifierFlags = ((long)StandardFlags & ~INTERFACE) | DEFAULT,
389 InterfaceMethodMask = ABSTRACT | PRIVATE | STATIC | PUBLIC | STRICTFP | DEFAULT,
390 AnnotationTypeElementMask = ABSTRACT | PUBLIC,
391 LocalVarFlags = FINAL | PARAMETER,
392 ReceiverParamFlags = PARAMETER;
393
394
395 public static Set<Modifier> asModifierSet(long flags) {
396 Set<Modifier> modifiers = modifierSets.get(flags);
397 if (modifiers == null) {
398 modifiers = java.util.EnumSet.noneOf(Modifier.class);
399 if (0 != (flags & PUBLIC)) modifiers.add(Modifier.PUBLIC);
400 if (0 != (flags & PROTECTED)) modifiers.add(Modifier.PROTECTED);
401 if (0 != (flags & PRIVATE)) modifiers.add(Modifier.PRIVATE);
402 if (0 != (flags & ABSTRACT)) modifiers.add(Modifier.ABSTRACT);
403 if (0 != (flags & STATIC)) modifiers.add(Modifier.STATIC);
404 if (0 != (flags & FINAL)) modifiers.add(Modifier.FINAL);
405 if (0 != (flags & TRANSIENT)) modifiers.add(Modifier.TRANSIENT);
406 if (0 != (flags & VOLATILE)) modifiers.add(Modifier.VOLATILE);
407 if (0 != (flags & SYNCHRONIZED))
408 modifiers.add(Modifier.SYNCHRONIZED);
409 if (0 != (flags & NATIVE)) modifiers.add(Modifier.NATIVE);
410 if (0 != (flags & STRICTFP)) modifiers.add(Modifier.STRICTFP);
411 if (0 != (flags & DEFAULT)) modifiers.add(Modifier.DEFAULT);
412 modifiers = Collections.unmodifiableSet(modifiers);
413 modifierSets.put(flags, modifiers);
414 }
415 return modifiers;
416 }
417
418 // Cache of modifier sets.
419 private static final Map<Long, Set<Modifier>> modifierSets = new ConcurrentHashMap<>(64);
420
421 public static boolean isStatic(Symbol symbol) {
422 return (symbol.flags() & STATIC) != 0;
423 }
424
425 public static boolean isEnum(Symbol symbol) {
426 return (symbol.flags() & ENUM) != 0;
427 }
428
429 public static boolean isConstant(Symbol.VarSymbol symbol) {
430 return symbol.getConstValue() != null;
431 }
432
433
434 public enum Flag {
435 PUBLIC(Flags.PUBLIC),
436 PRIVATE(Flags.PRIVATE),
437 PROTECTED(Flags.PROTECTED),
438 STATIC(Flags.STATIC),
439 FINAL(Flags.FINAL),
440 SYNCHRONIZED(Flags.SYNCHRONIZED),
441 VOLATILE(Flags.VOLATILE),
442 TRANSIENT(Flags.TRANSIENT),
443 NATIVE(Flags.NATIVE),
444 INTERFACE(Flags.INTERFACE),
445 ABSTRACT(Flags.ABSTRACT),
446 DEFAULT(Flags.DEFAULT),
447 STRICTFP(Flags.STRICTFP),
448 BRIDGE(Flags.BRIDGE),
449 SYNTHETIC(Flags.SYNTHETIC),
450 ANNOTATION(Flags.ANNOTATION),
451 DEPRECATED(Flags.DEPRECATED),
452 HASINIT(Flags.HASINIT),
453 BLOCK(Flags.BLOCK),
454 ENUM(Flags.ENUM),
455 MANDATED(Flags.MANDATED),
456 NOOUTERTHIS(Flags.NOOUTERTHIS),
457 EXISTS(Flags.EXISTS),
458 COMPOUND(Flags.COMPOUND),
459 CLASS_SEEN(Flags.CLASS_SEEN),
460 SOURCE_SEEN(Flags.SOURCE_SEEN),
461 LOCKED(Flags.LOCKED),
462 UNATTRIBUTED(Flags.UNATTRIBUTED),
463 ANONCONSTR(Flags.ANONCONSTR),
464 ACYCLIC(Flags.ACYCLIC),
465 PARAMETER(Flags.PARAMETER),
466 VARARGS(Flags.VARARGS),
467 ACYCLIC_ANN(Flags.ACYCLIC_ANN),
468 GENERATEDCONSTR(Flags.GENERATEDCONSTR),
469 HYPOTHETICAL(Flags.HYPOTHETICAL),
470 PROPRIETARY(Flags.PROPRIETARY),
471 UNION(Flags.UNION),
472 EFFECTIVELY_FINAL(Flags.EFFECTIVELY_FINAL),
473 CLASH(Flags.CLASH),
474 AUXILIARY(Flags.AUXILIARY),
475 NOT_IN_PROFILE(Flags.NOT_IN_PROFILE),
476 BAD_OVERRIDE(Flags.BAD_OVERRIDE),
477 SIGNATURE_POLYMORPHIC(Flags.SIGNATURE_POLYMORPHIC),
478 THROWS(Flags.THROWS),
479 LAMBDA_METHOD(Flags.LAMBDA_METHOD),
480 TYPE_TRANSLATED(Flags.TYPE_TRANSLATED),
481 MODULE(Flags.MODULE),
482 AUTOMATIC_MODULE(Flags.AUTOMATIC_MODULE),
483 SYSTEM_MODULE(Flags.SYSTEM_MODULE),
484 DEPRECATED_ANNOTATION(Flags.DEPRECATED_ANNOTATION),
485 DEPRECATED_REMOVAL(Flags.DEPRECATED_REMOVAL),
486 HAS_RESOURCE(Flags.HAS_RESOURCE),
487 POTENTIALLY_AMBIGUOUS(Flags.POTENTIALLY_AMBIGUOUS),
488 ANONCONSTR_BASED(Flags.ANONCONSTR_BASED),
489 NAME_FILLED(Flags.NAME_FILLED),
490 PREVIEW_API(Flags.PREVIEW_API),
491 PREVIEW_ESSENTIAL_API(Flags.PREVIEW_ESSENTIAL_API),
492 MATCH_BINDING(Flags.MATCH_BINDING),
493 MATCH_BINDING_TO_OUTER(Flags.MATCH_BINDING_TO_OUTER),
494 RECORD(Flags.RECORD);
495
496 Flag(long flag) {
497 this.value = flag;
498 this.lowercaseName = StringUtils.toLowerCase(name());
499 }
500
501 @Override
502 public String toString() {
503 return lowercaseName;
504 }
505
506 final long value;
507 final String lowercaseName;
508 }
509
510 }