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 Flags()48 private Flags() {} // uninstantiable 49 toString(long flags)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 asFlagSet(long flags)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 /** Modifier masks. 323 */ 324 public static final int 325 AccessFlags = PUBLIC | PROTECTED | PRIVATE, 326 LocalClassFlags = FINAL | ABSTRACT | STRICTFP | ENUM | SYNTHETIC, 327 MemberClassFlags = LocalClassFlags | INTERFACE | AccessFlags, 328 ClassFlags = LocalClassFlags | INTERFACE | PUBLIC | ANNOTATION, 329 InterfaceVarFlags = FINAL | STATIC | PUBLIC, 330 VarFlags = AccessFlags | FINAL | STATIC | 331 VOLATILE | TRANSIENT | ENUM, 332 ConstructorFlags = AccessFlags, 333 InterfaceMethodFlags = ABSTRACT | PUBLIC, 334 MethodFlags = AccessFlags | ABSTRACT | STATIC | NATIVE | 335 SYNCHRONIZED | FINAL | STRICTFP; 336 public static final long 337 ExtendedStandardFlags = (long)StandardFlags | DEFAULT, 338 ModifierFlags = ((long)StandardFlags & ~INTERFACE) | DEFAULT, 339 InterfaceMethodMask = ABSTRACT | PRIVATE | STATIC | PUBLIC | STRICTFP | DEFAULT, 340 AnnotationTypeElementMask = ABSTRACT | PUBLIC, 341 LocalVarFlags = FINAL | PARAMETER, 342 ReceiverParamFlags = PARAMETER; 343 344 asModifierSet(long flags)345 public static Set<Modifier> asModifierSet(long flags) { 346 Set<Modifier> modifiers = modifierSets.get(flags); 347 if (modifiers == null) { 348 modifiers = java.util.EnumSet.noneOf(Modifier.class); 349 if (0 != (flags & PUBLIC)) modifiers.add(Modifier.PUBLIC); 350 if (0 != (flags & PROTECTED)) modifiers.add(Modifier.PROTECTED); 351 if (0 != (flags & PRIVATE)) modifiers.add(Modifier.PRIVATE); 352 if (0 != (flags & ABSTRACT)) modifiers.add(Modifier.ABSTRACT); 353 if (0 != (flags & STATIC)) modifiers.add(Modifier.STATIC); 354 if (0 != (flags & FINAL)) modifiers.add(Modifier.FINAL); 355 if (0 != (flags & TRANSIENT)) modifiers.add(Modifier.TRANSIENT); 356 if (0 != (flags & VOLATILE)) modifiers.add(Modifier.VOLATILE); 357 if (0 != (flags & SYNCHRONIZED)) 358 modifiers.add(Modifier.SYNCHRONIZED); 359 if (0 != (flags & NATIVE)) modifiers.add(Modifier.NATIVE); 360 if (0 != (flags & STRICTFP)) modifiers.add(Modifier.STRICTFP); 361 if (0 != (flags & DEFAULT)) modifiers.add(Modifier.DEFAULT); 362 modifiers = Collections.unmodifiableSet(modifiers); 363 modifierSets.put(flags, modifiers); 364 } 365 return modifiers; 366 } 367 368 // Cache of modifier sets. 369 private static final Map<Long, Set<Modifier>> modifierSets = new ConcurrentHashMap<>(64); 370 isStatic(Symbol symbol)371 public static boolean isStatic(Symbol symbol) { 372 return (symbol.flags() & STATIC) != 0; 373 } 374 isEnum(Symbol symbol)375 public static boolean isEnum(Symbol symbol) { 376 return (symbol.flags() & ENUM) != 0; 377 } 378 isConstant(Symbol.VarSymbol symbol)379 public static boolean isConstant(Symbol.VarSymbol symbol) { 380 return symbol.getConstValue() != null; 381 } 382 383 384 public enum Flag { 385 PUBLIC(Flags.PUBLIC), 386 PRIVATE(Flags.PRIVATE), 387 PROTECTED(Flags.PROTECTED), 388 STATIC(Flags.STATIC), 389 FINAL(Flags.FINAL), 390 SYNCHRONIZED(Flags.SYNCHRONIZED), 391 VOLATILE(Flags.VOLATILE), 392 TRANSIENT(Flags.TRANSIENT), 393 NATIVE(Flags.NATIVE), 394 INTERFACE(Flags.INTERFACE), 395 ABSTRACT(Flags.ABSTRACT), 396 DEFAULT(Flags.DEFAULT), 397 STRICTFP(Flags.STRICTFP), 398 BRIDGE(Flags.BRIDGE), 399 SYNTHETIC(Flags.SYNTHETIC), 400 ANNOTATION(Flags.ANNOTATION), 401 DEPRECATED(Flags.DEPRECATED), 402 HASINIT(Flags.HASINIT), 403 BLOCK(Flags.BLOCK), 404 ENUM(Flags.ENUM), 405 MANDATED(Flags.MANDATED), 406 NOOUTERTHIS(Flags.NOOUTERTHIS), 407 EXISTS(Flags.EXISTS), 408 COMPOUND(Flags.COMPOUND), 409 CLASS_SEEN(Flags.CLASS_SEEN), 410 SOURCE_SEEN(Flags.SOURCE_SEEN), 411 LOCKED(Flags.LOCKED), 412 UNATTRIBUTED(Flags.UNATTRIBUTED), 413 ANONCONSTR(Flags.ANONCONSTR), 414 ACYCLIC(Flags.ACYCLIC), 415 PARAMETER(Flags.PARAMETER), 416 VARARGS(Flags.VARARGS), 417 ACYCLIC_ANN(Flags.ACYCLIC_ANN), 418 GENERATEDCONSTR(Flags.GENERATEDCONSTR), 419 HYPOTHETICAL(Flags.HYPOTHETICAL), 420 PROPRIETARY(Flags.PROPRIETARY), 421 UNION(Flags.UNION), 422 EFFECTIVELY_FINAL(Flags.EFFECTIVELY_FINAL), 423 CLASH(Flags.CLASH), 424 AUXILIARY(Flags.AUXILIARY), 425 NOT_IN_PROFILE(Flags.NOT_IN_PROFILE), 426 BAD_OVERRIDE(Flags.BAD_OVERRIDE), 427 SIGNATURE_POLYMORPHIC(Flags.SIGNATURE_POLYMORPHIC), 428 THROWS(Flags.THROWS), 429 LAMBDA_METHOD(Flags.LAMBDA_METHOD), 430 TYPE_TRANSLATED(Flags.TYPE_TRANSLATED), 431 MODULE(Flags.MODULE), 432 AUTOMATIC_MODULE(Flags.AUTOMATIC_MODULE), 433 SYSTEM_MODULE(Flags.SYSTEM_MODULE), 434 DEPRECATED_ANNOTATION(Flags.DEPRECATED_ANNOTATION), 435 DEPRECATED_REMOVAL(Flags.DEPRECATED_REMOVAL), 436 HAS_RESOURCE(Flags.HAS_RESOURCE), 437 POTENTIALLY_AMBIGUOUS(Flags.POTENTIALLY_AMBIGUOUS), 438 ANONCONSTR_BASED(Flags.ANONCONSTR_BASED); 439 Flag(long flag)440 Flag(long flag) { 441 this.value = flag; 442 this.lowercaseName = StringUtils.toLowerCase(name()); 443 } 444 445 @Override toString()446 public String toString() { 447 return lowercaseName; 448 } 449 450 final long value; 451 final String lowercaseName; 452 } 453 454 } 455