1 /*
2 * Copyright (c) 1999, 2015, 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 been deprecated and marked for removal.
298 */
299 public static final long DEPRECATED_REMOVAL = 1L<<54;
300
301 /** Modifier masks.
302 */
303 public static final int
304 AccessFlags = PUBLIC | PROTECTED | PRIVATE,
305 LocalClassFlags = FINAL | ABSTRACT | STRICTFP | ENUM | SYNTHETIC,
306 MemberClassFlags = LocalClassFlags | INTERFACE | AccessFlags,
307 ClassFlags = LocalClassFlags | INTERFACE | PUBLIC | ANNOTATION,
308 InterfaceVarFlags = FINAL | STATIC | PUBLIC,
309 VarFlags = AccessFlags | FINAL | STATIC |
310 VOLATILE | TRANSIENT | ENUM,
311 ConstructorFlags = AccessFlags,
312 InterfaceMethodFlags = ABSTRACT | PUBLIC,
313 MethodFlags = AccessFlags | ABSTRACT | STATIC | NATIVE |
314 SYNCHRONIZED | FINAL | STRICTFP;
315 public static final long
316 ExtendedStandardFlags = (long)StandardFlags | DEFAULT,
317 ModifierFlags = ((long)StandardFlags & ~INTERFACE) | DEFAULT,
318 InterfaceMethodMask = ABSTRACT | PRIVATE | STATIC | PUBLIC | STRICTFP | DEFAULT,
319 AnnotationTypeElementMask = ABSTRACT | PUBLIC,
320 LocalVarFlags = FINAL | PARAMETER,
321 ReceiverParamFlags = PARAMETER;
322
323
324 public static Set<Modifier> asModifierSet(long flags) {
325 Set<Modifier> modifiers = modifierSets.get(flags);
326 if (modifiers == null) {
327 modifiers = java.util.EnumSet.noneOf(Modifier.class);
328 if (0 != (flags & PUBLIC)) modifiers.add(Modifier.PUBLIC);
329 if (0 != (flags & PROTECTED)) modifiers.add(Modifier.PROTECTED);
330 if (0 != (flags & PRIVATE)) modifiers.add(Modifier.PRIVATE);
331 if (0 != (flags & ABSTRACT)) modifiers.add(Modifier.ABSTRACT);
332 if (0 != (flags & STATIC)) modifiers.add(Modifier.STATIC);
333 if (0 != (flags & FINAL)) modifiers.add(Modifier.FINAL);
334 if (0 != (flags & TRANSIENT)) modifiers.add(Modifier.TRANSIENT);
335 if (0 != (flags & VOLATILE)) modifiers.add(Modifier.VOLATILE);
336 if (0 != (flags & SYNCHRONIZED))
337 modifiers.add(Modifier.SYNCHRONIZED);
338 if (0 != (flags & NATIVE)) modifiers.add(Modifier.NATIVE);
339 if (0 != (flags & STRICTFP)) modifiers.add(Modifier.STRICTFP);
340 if (0 != (flags & DEFAULT)) modifiers.add(Modifier.DEFAULT);
341 modifiers = Collections.unmodifiableSet(modifiers);
342 modifierSets.put(flags, modifiers);
343 }
344 return modifiers;
345 }
346
347 // Cache of modifier sets.
348 private static final Map<Long, Set<Modifier>> modifierSets = new ConcurrentHashMap<>(64);
349
350 public static boolean isStatic(Symbol symbol) {
351 return (symbol.flags() & STATIC) != 0;
352 }
353
354 public static boolean isEnum(Symbol symbol) {
355 return (symbol.flags() & ENUM) != 0;
356 }
357
358 public static boolean isConstant(Symbol.VarSymbol symbol) {
359 return symbol.getConstValue() != null;
360 }
361
362
363 public enum Flag {
364 PUBLIC(Flags.PUBLIC),
365 PRIVATE(Flags.PRIVATE),
366 PROTECTED(Flags.PROTECTED),
367 STATIC(Flags.STATIC),
368 FINAL(Flags.FINAL),
369 SYNCHRONIZED(Flags.SYNCHRONIZED),
370 VOLATILE(Flags.VOLATILE),
371 TRANSIENT(Flags.TRANSIENT),
372 NATIVE(Flags.NATIVE),
373 INTERFACE(Flags.INTERFACE),
374 ABSTRACT(Flags.ABSTRACT),
375 DEFAULT(Flags.DEFAULT),
376 STRICTFP(Flags.STRICTFP),
377 BRIDGE(Flags.BRIDGE),
378 SYNTHETIC(Flags.SYNTHETIC),
379 ANNOTATION(Flags.ANNOTATION),
380 DEPRECATED(Flags.DEPRECATED),
381 HASINIT(Flags.HASINIT),
382 BLOCK(Flags.BLOCK),
383 ENUM(Flags.ENUM),
384 MANDATED(Flags.MANDATED),
385 NOOUTERTHIS(Flags.NOOUTERTHIS),
386 EXISTS(Flags.EXISTS),
387 COMPOUND(Flags.COMPOUND),
388 CLASS_SEEN(Flags.CLASS_SEEN),
389 SOURCE_SEEN(Flags.SOURCE_SEEN),
390 LOCKED(Flags.LOCKED),
391 UNATTRIBUTED(Flags.UNATTRIBUTED),
392 ANONCONSTR(Flags.ANONCONSTR),
393 ACYCLIC(Flags.ACYCLIC),
394 PARAMETER(Flags.PARAMETER),
395 VARARGS(Flags.VARARGS),
396 ACYCLIC_ANN(Flags.ACYCLIC_ANN),
397 GENERATEDCONSTR(Flags.GENERATEDCONSTR),
398 HYPOTHETICAL(Flags.HYPOTHETICAL),
399 PROPRIETARY(Flags.PROPRIETARY),
400 UNION(Flags.UNION),
401 EFFECTIVELY_FINAL(Flags.EFFECTIVELY_FINAL),
402 CLASH(Flags.CLASH),
403 AUXILIARY(Flags.AUXILIARY),
404 NOT_IN_PROFILE(Flags.NOT_IN_PROFILE),
405 BAD_OVERRIDE(Flags.BAD_OVERRIDE),
406 SIGNATURE_POLYMORPHIC(Flags.SIGNATURE_POLYMORPHIC),
407 THROWS(Flags.THROWS),
408 LAMBDA_METHOD(Flags.LAMBDA_METHOD),
409 TYPE_TRANSLATED(Flags.TYPE_TRANSLATED),
410 MODULE(Flags.MODULE),
411 DEPRECATED_REMOVAL(Flags.DEPRECATED_REMOVAL);
412
413 Flag(long flag) {
414 this.value = flag;
415 this.lowercaseName = StringUtils.toLowerCase(name());
416 }
417
418 @Override
419 public String toString() {
420 return lowercaseName;
421 }
422
423 final long value;
424 final String lowercaseName;
425 }
426
427 }