1 /*
2 * Copyright (c) 1999, 2016, 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;
290
291 /**
292 * Flag to indicate the given ModuleSymbol is a system module.
293 */
294 public static final long SYSTEM_MODULE = 1L<<53;
295
296 /**
297 * Flag to indicate the given symbol has a @Deprecated annotation.
298 */
299 public static final long DEPRECATED_ANNOTATION = 1L<<54;
300
301 /**
302 * Flag to indicate the given symbol has been deprecated and marked for removal.
303 */
304 public static final long DEPRECATED_REMOVAL = 1L<<55;
305
306 /**
307 * Flag to indicate the given PackageSymbol contains any non-.java and non-.class resources.
308 */
309 public static final long HAS_RESOURCE = 1L<<56;
310
311 /**
312 * Flag for synthesized default constructors of anonymous classes that have an enclosing expression.
313 */
314 public static final long ANONCONSTR_BASED = 1L<<57;
315
316 /**
317 * Flag that marks finalize block as body-only, should not be copied into catch clauses.
318 * Used to implement try-with-resources.
319 */
320 public static final long BODY_ONLY_FINALIZE = 1L<<17; //blocks only
321
322 /**
323 * Flag to indicate the given ParamSymbol has a user-friedly name filled.
324 */
325 public static final long NAME_FILLED = 1L<<58; //ParamSymbols only
326
327 /** Modifier masks.
328 */
329 public static final int
330 AccessFlags = PUBLIC | PROTECTED | PRIVATE,
331 LocalClassFlags = FINAL | ABSTRACT | STRICTFP | ENUM | SYNTHETIC,
332 MemberClassFlags = LocalClassFlags | INTERFACE | AccessFlags,
333 ClassFlags = LocalClassFlags | INTERFACE | PUBLIC | ANNOTATION,
334 InterfaceVarFlags = FINAL | STATIC | PUBLIC,
335 VarFlags = AccessFlags | FINAL | STATIC |
336 VOLATILE | TRANSIENT | ENUM,
337 ConstructorFlags = AccessFlags,
338 InterfaceMethodFlags = ABSTRACT | PUBLIC,
339 MethodFlags = AccessFlags | ABSTRACT | STATIC | NATIVE |
340 SYNCHRONIZED | FINAL | STRICTFP;
341 public static final long
342 ExtendedStandardFlags = (long)StandardFlags | DEFAULT,
343 ModifierFlags = ((long)StandardFlags & ~INTERFACE) | DEFAULT,
344 InterfaceMethodMask = ABSTRACT | PRIVATE | STATIC | PUBLIC | STRICTFP | DEFAULT,
345 AnnotationTypeElementMask = ABSTRACT | PUBLIC,
346 LocalVarFlags = FINAL | PARAMETER,
347 ReceiverParamFlags = PARAMETER;
348
349
350 public static Set<Modifier> asModifierSet(long flags) {
351 Set<Modifier> modifiers = modifierSets.get(flags);
352 if (modifiers == null) {
353 modifiers = java.util.EnumSet.noneOf(Modifier.class);
354 if (0 != (flags & PUBLIC)) modifiers.add(Modifier.PUBLIC);
355 if (0 != (flags & PROTECTED)) modifiers.add(Modifier.PROTECTED);
356 if (0 != (flags & PRIVATE)) modifiers.add(Modifier.PRIVATE);
357 if (0 != (flags & ABSTRACT)) modifiers.add(Modifier.ABSTRACT);
358 if (0 != (flags & STATIC)) modifiers.add(Modifier.STATIC);
359 if (0 != (flags & FINAL)) modifiers.add(Modifier.FINAL);
360 if (0 != (flags & TRANSIENT)) modifiers.add(Modifier.TRANSIENT);
361 if (0 != (flags & VOLATILE)) modifiers.add(Modifier.VOLATILE);
362 if (0 != (flags & SYNCHRONIZED))
363 modifiers.add(Modifier.SYNCHRONIZED);
364 if (0 != (flags & NATIVE)) modifiers.add(Modifier.NATIVE);
365 if (0 != (flags & STRICTFP)) modifiers.add(Modifier.STRICTFP);
366 if (0 != (flags & DEFAULT)) modifiers.add(Modifier.DEFAULT);
367 modifiers = Collections.unmodifiableSet(modifiers);
368 modifierSets.put(flags, modifiers);
369 }
370 return modifiers;
371 }
372
373 // Cache of modifier sets.
374 private static final Map<Long, Set<Modifier>> modifierSets = new ConcurrentHashMap<>(64);
375
376 public static boolean isStatic(Symbol symbol) {
377 return (symbol.flags() & STATIC) != 0;
378 }
379
380 public static boolean isEnum(Symbol symbol) {
381 return (symbol.flags() & ENUM) != 0;
382 }
383
384 public static boolean isConstant(Symbol.VarSymbol symbol) {
385 return symbol.getConstValue() != null;
386 }
387
388
389 public enum Flag {
390 PUBLIC(Flags.PUBLIC),
391 PRIVATE(Flags.PRIVATE),
392 PROTECTED(Flags.PROTECTED),
393 STATIC(Flags.STATIC),
394 FINAL(Flags.FINAL),
395 SYNCHRONIZED(Flags.SYNCHRONIZED),
396 VOLATILE(Flags.VOLATILE),
397 TRANSIENT(Flags.TRANSIENT),
398 NATIVE(Flags.NATIVE),
399 INTERFACE(Flags.INTERFACE),
400 ABSTRACT(Flags.ABSTRACT),
401 DEFAULT(Flags.DEFAULT),
402 STRICTFP(Flags.STRICTFP),
403 BRIDGE(Flags.BRIDGE),
404 SYNTHETIC(Flags.SYNTHETIC),
405 ANNOTATION(Flags.ANNOTATION),
406 DEPRECATED(Flags.DEPRECATED),
407 HASINIT(Flags.HASINIT),
408 BLOCK(Flags.BLOCK),
409 ENUM(Flags.ENUM),
410 MANDATED(Flags.MANDATED),
411 NOOUTERTHIS(Flags.NOOUTERTHIS),
412 EXISTS(Flags.EXISTS),
413 COMPOUND(Flags.COMPOUND),
414 CLASS_SEEN(Flags.CLASS_SEEN),
415 SOURCE_SEEN(Flags.SOURCE_SEEN),
416 LOCKED(Flags.LOCKED),
417 UNATTRIBUTED(Flags.UNATTRIBUTED),
418 ANONCONSTR(Flags.ANONCONSTR),
419 ACYCLIC(Flags.ACYCLIC),
420 PARAMETER(Flags.PARAMETER),
421 VARARGS(Flags.VARARGS),
422 ACYCLIC_ANN(Flags.ACYCLIC_ANN),
423 GENERATEDCONSTR(Flags.GENERATEDCONSTR),
424 HYPOTHETICAL(Flags.HYPOTHETICAL),
425 PROPRIETARY(Flags.PROPRIETARY),
426 UNION(Flags.UNION),
427 EFFECTIVELY_FINAL(Flags.EFFECTIVELY_FINAL),
428 CLASH(Flags.CLASH),
429 AUXILIARY(Flags.AUXILIARY),
430 NOT_IN_PROFILE(Flags.NOT_IN_PROFILE),
431 BAD_OVERRIDE(Flags.BAD_OVERRIDE),
432 SIGNATURE_POLYMORPHIC(Flags.SIGNATURE_POLYMORPHIC),
433 THROWS(Flags.THROWS),
434 LAMBDA_METHOD(Flags.LAMBDA_METHOD),
435 TYPE_TRANSLATED(Flags.TYPE_TRANSLATED),
436 MODULE(Flags.MODULE),
437 AUTOMATIC_MODULE(Flags.AUTOMATIC_MODULE),
438 SYSTEM_MODULE(Flags.SYSTEM_MODULE),
439 DEPRECATED_ANNOTATION(Flags.DEPRECATED_ANNOTATION),
440 DEPRECATED_REMOVAL(Flags.DEPRECATED_REMOVAL),
441 HAS_RESOURCE(Flags.HAS_RESOURCE),
442 POTENTIALLY_AMBIGUOUS(Flags.POTENTIALLY_AMBIGUOUS),
443 ANONCONSTR_BASED(Flags.ANONCONSTR_BASED),
444 NAME_FILLED(Flags.NAME_FILLED);
445
446 Flag(long flag) {
447 this.value = flag;
448 this.lowercaseName = StringUtils.toLowerCase(name());
449 }
450
451 @Override
452 public String toString() {
453 return lowercaseName;
454 }
455
456 final long value;
457 final String lowercaseName;
458 }
459
460 }