1 /* 2 * Copyright (c) 1999, 2014, 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 33 import javax.lang.model.element.Modifier; 34 35 import com.sun.tools.javac.util.Assert; 36 import com.sun.tools.javac.util.StringUtils; 37 38 /** Access flags and other modifiers for Java classes and members. 39 * 40 * <p><b>This is NOT part of any supported API. 41 * If you write code that depends on this, you do so at your own risk. 42 * This code and its internal interfaces are subject to change or 43 * deletion without notice.</b> 44 */ 45 public class Flags { 46 Flags()47 private Flags() {} // uninstantiable 48 toString(long flags)49 public static String toString(long flags) { 50 StringBuilder buf = new StringBuilder(); 51 String sep = ""; 52 for (Flag flag : asFlagSet(flags)) { 53 buf.append(sep); 54 buf.append(flag); 55 sep = " "; 56 } 57 return buf.toString(); 58 } 59 asFlagSet(long flags)60 public static EnumSet<Flag> asFlagSet(long flags) { 61 EnumSet<Flag> flagSet = EnumSet.noneOf(Flag.class); 62 for (Flag flag : Flag.values()) { 63 if ((flags & flag.value) != 0) { 64 flagSet.add(flag); 65 flags &= ~flag.value; 66 } 67 } 68 Assert.check(flags == 0, "Flags parameter contains unknown flags " + flags); 69 return flagSet; 70 } 71 72 /* Standard Java flags. 73 */ 74 public static final int PUBLIC = 1; 75 public static final int PRIVATE = 1<<1; 76 public static final int PROTECTED = 1<<2; 77 public static final int STATIC = 1<<3; 78 public static final int FINAL = 1<<4; 79 public static final int SYNCHRONIZED = 1<<5; 80 public static final int VOLATILE = 1<<6; 81 public static final int TRANSIENT = 1<<7; 82 public static final int NATIVE = 1<<8; 83 public static final int INTERFACE = 1<<9; 84 public static final int ABSTRACT = 1<<10; 85 public static final int STRICTFP = 1<<11; 86 87 /* Flag that marks a symbol synthetic, added in classfile v49.0. */ 88 public static final int SYNTHETIC = 1<<12; 89 90 /** Flag that marks attribute interfaces, added in classfile v49.0. */ 91 public static final int ANNOTATION = 1<<13; 92 93 /** An enumeration type or an enumeration constant, added in 94 * classfile v49.0. */ 95 public static final int ENUM = 1<<14; 96 97 /** Added in SE8, represents constructs implicitly declared in source. */ 98 public static final int MANDATED = 1<<15; 99 100 public static final int StandardFlags = 0x0fff; 101 102 // Because the following access flags are overloaded with other 103 // bit positions, we translate them when reading and writing class 104 // files into unique bits positions: ACC_SYNTHETIC <-> SYNTHETIC, 105 // for example. 106 public static final int ACC_SUPER = 0x0020; 107 public static final int ACC_BRIDGE = 0x0040; 108 public static final int ACC_VARARGS = 0x0080; 109 110 /***************************************** 111 * Internal compiler flags (no bits in the lower 16). 112 *****************************************/ 113 114 /** Flag is set if symbol is deprecated. 115 */ 116 public static final int DEPRECATED = 1<<17; 117 118 /** Flag is set for a variable symbol if the variable's definition 119 * has an initializer part. 120 */ 121 public static final int HASINIT = 1<<18; 122 123 /** Flag is set for compiler-generated anonymous method symbols 124 * that `own' an initializer block. 125 */ 126 public static final int BLOCK = 1<<20; 127 128 /** Flag is set for compiler-generated abstract methods that implement 129 * an interface method (Miranda methods). 130 */ 131 public static final int IPROXY = 1<<21; 132 133 /** Flag is set for nested classes that do not access instance members 134 * or `this' of an outer class and therefore don't need to be passed 135 * a this$n reference. This value is currently set only for anonymous 136 * classes in superclass constructor calls and only for pre 1.4 targets. 137 * todo: use this value for optimizing away this$n parameters in 138 * other cases. 139 */ 140 public static final int NOOUTERTHIS = 1<<22; 141 142 /** Flag is set for package symbols if a package has a member or 143 * directory and therefore exists. 144 */ 145 public static final int EXISTS = 1<<23; 146 147 /** Flag is set for compiler-generated compound classes 148 * representing multiple variable bounds 149 */ 150 public static final int COMPOUND = 1<<24; 151 152 /** Flag is set for class symbols if a class file was found for this class. 153 */ 154 public static final int CLASS_SEEN = 1<<25; 155 156 /** Flag is set for class symbols if a source file was found for this 157 * class. 158 */ 159 public static final int SOURCE_SEEN = 1<<26; 160 161 /* State flags (are reset during compilation). 162 */ 163 164 /** Flag for class symbols is set and later re-set as a lock in 165 * Enter to detect cycles in the superclass/superinterface 166 * relations. Similarly for constructor call cycle detection in 167 * Attr. 168 */ 169 public static final int LOCKED = 1<<27; 170 171 /** Flag for class symbols is set and later re-set to indicate that a class 172 * has been entered but has not yet been attributed. 173 */ 174 public static final int UNATTRIBUTED = 1<<28; 175 176 /** Flag for synthesized default constructors of anonymous classes. 177 */ 178 public static final int ANONCONSTR = 1<<29; 179 180 /** Flag for class symbols to indicate it has been checked and found 181 * acyclic. 182 */ 183 public static final int ACYCLIC = 1<<30; 184 185 /** Flag that marks bridge methods. 186 */ 187 public static final long BRIDGE = 1L<<31; 188 189 /** Flag that marks formal parameters. 190 */ 191 public static final long PARAMETER = 1L<<33; 192 193 /** Flag that marks varargs methods. 194 */ 195 public static final long VARARGS = 1L<<34; 196 197 /** Flag for annotation type symbols to indicate it has been 198 * checked and found acyclic. 199 */ 200 public static final long ACYCLIC_ANN = 1L<<35; 201 202 /** Flag that marks a generated default constructor. 203 */ 204 public static final long GENERATEDCONSTR = 1L<<36; 205 206 /** Flag that marks a hypothetical method that need not really be 207 * generated in the binary, but is present in the symbol table to 208 * simplify checking for erasure clashes - also used for 292 poly sig methods. 209 */ 210 public static final long HYPOTHETICAL = 1L<<37; 211 212 /** 213 * Flag that marks an internal proprietary class. 214 */ 215 public static final long PROPRIETARY = 1L<<38; 216 217 /** 218 * Flag that marks a multi-catch parameter. 219 */ 220 public static final long UNION = 1L<<39; 221 222 /** 223 * Flag that marks a special kind of bridge method (the ones that 224 * come from restricted supertype bounds). 225 */ 226 public static final long OVERRIDE_BRIDGE = 1L<<40; 227 228 /** 229 * Flag that marks an 'effectively final' local variable. 230 */ 231 public static final long EFFECTIVELY_FINAL = 1L<<41; 232 233 /** 234 * Flag that marks non-override equivalent methods with the same signature. 235 */ 236 public static final long CLASH = 1L<<42; 237 238 /** 239 * Flag that marks either a default method or an interface containing default methods. 240 */ 241 public static final long DEFAULT = 1L<<43; 242 243 /** 244 * Flag that marks class as auxiliary, ie a non-public class following 245 * the public class in a source file, that could block implicit compilation. 246 */ 247 public static final long AUXILIARY = 1L<<44; 248 249 /** 250 * Flag that marks that a symbol is not available in the current profile 251 */ 252 public static final long NOT_IN_PROFILE = 1L<<45; 253 254 /** 255 * Flag that indicates that an override error has been detected by Check. 256 */ 257 public static final long BAD_OVERRIDE = 1L<<45; 258 259 /** 260 * Flag that indicates a signature polymorphic method (292). 261 */ 262 public static final long SIGNATURE_POLYMORPHIC = 1L<<46; 263 264 /** 265 * Flag that indicates that an inference variable is used in a 'throws' clause. 266 */ 267 public static final long THROWS = 1L<<47; 268 269 /** 270 * Flag that marks potentially ambiguous overloads 271 */ 272 public static final long POTENTIALLY_AMBIGUOUS = 1L<<48; 273 274 /** 275 * Flag that marks a synthetic method body for a lambda expression 276 */ 277 public static final long LAMBDA_METHOD = 1L<<49; 278 279 /** 280 * Flag to control recursion in TransTypes 281 */ 282 public static final long TYPE_TRANSLATED = 1L<<50; 283 284 /** Modifier masks. 285 */ 286 public static final int 287 AccessFlags = PUBLIC | PROTECTED | PRIVATE, 288 LocalClassFlags = FINAL | ABSTRACT | STRICTFP | ENUM | SYNTHETIC, 289 MemberClassFlags = LocalClassFlags | INTERFACE | AccessFlags, 290 ClassFlags = LocalClassFlags | INTERFACE | PUBLIC | ANNOTATION, 291 InterfaceVarFlags = FINAL | STATIC | PUBLIC, 292 VarFlags = AccessFlags | FINAL | STATIC | 293 VOLATILE | TRANSIENT | ENUM, 294 ConstructorFlags = AccessFlags, 295 InterfaceMethodFlags = ABSTRACT | PUBLIC, 296 MethodFlags = AccessFlags | ABSTRACT | STATIC | NATIVE | 297 SYNCHRONIZED | FINAL | STRICTFP; 298 public static final long 299 ExtendedStandardFlags = (long)StandardFlags | DEFAULT, 300 ModifierFlags = ((long)StandardFlags & ~INTERFACE) | DEFAULT, 301 InterfaceMethodMask = ABSTRACT | STATIC | PUBLIC | STRICTFP | DEFAULT, 302 AnnotationTypeElementMask = ABSTRACT | PUBLIC, 303 LocalVarFlags = FINAL | PARAMETER, 304 ReceiverParamFlags = PARAMETER; 305 306 asModifierSet(long flags)307 public static Set<Modifier> asModifierSet(long flags) { 308 Set<Modifier> modifiers = modifierSets.get(flags); 309 if (modifiers == null) { 310 modifiers = java.util.EnumSet.noneOf(Modifier.class); 311 if (0 != (flags & PUBLIC)) modifiers.add(Modifier.PUBLIC); 312 if (0 != (flags & PROTECTED)) modifiers.add(Modifier.PROTECTED); 313 if (0 != (flags & PRIVATE)) modifiers.add(Modifier.PRIVATE); 314 if (0 != (flags & ABSTRACT)) modifiers.add(Modifier.ABSTRACT); 315 if (0 != (flags & STATIC)) modifiers.add(Modifier.STATIC); 316 if (0 != (flags & FINAL)) modifiers.add(Modifier.FINAL); 317 if (0 != (flags & TRANSIENT)) modifiers.add(Modifier.TRANSIENT); 318 if (0 != (flags & VOLATILE)) modifiers.add(Modifier.VOLATILE); 319 if (0 != (flags & SYNCHRONIZED)) 320 modifiers.add(Modifier.SYNCHRONIZED); 321 if (0 != (flags & NATIVE)) modifiers.add(Modifier.NATIVE); 322 if (0 != (flags & STRICTFP)) modifiers.add(Modifier.STRICTFP); 323 if (0 != (flags & DEFAULT)) modifiers.add(Modifier.DEFAULT); 324 modifiers = Collections.unmodifiableSet(modifiers); 325 modifierSets.put(flags, modifiers); 326 } 327 return modifiers; 328 } 329 330 // Cache of modifier sets. 331 private static final Map<Long, Set<Modifier>> modifierSets = 332 new java.util.concurrent.ConcurrentHashMap<Long, Set<Modifier>>(64); 333 isStatic(Symbol symbol)334 public static boolean isStatic(Symbol symbol) { 335 return (symbol.flags() & STATIC) != 0; 336 } 337 isEnum(Symbol symbol)338 public static boolean isEnum(Symbol symbol) { 339 return (symbol.flags() & ENUM) != 0; 340 } 341 isConstant(Symbol.VarSymbol symbol)342 public static boolean isConstant(Symbol.VarSymbol symbol) { 343 return symbol.getConstValue() != null; 344 } 345 346 347 public enum Flag { 348 PUBLIC(Flags.PUBLIC), 349 PRIVATE(Flags.PRIVATE), 350 PROTECTED(Flags.PROTECTED), 351 STATIC(Flags.STATIC), 352 FINAL(Flags.FINAL), 353 SYNCHRONIZED(Flags.SYNCHRONIZED), 354 VOLATILE(Flags.VOLATILE), 355 TRANSIENT(Flags.TRANSIENT), 356 NATIVE(Flags.NATIVE), 357 INTERFACE(Flags.INTERFACE), 358 ABSTRACT(Flags.ABSTRACT), 359 DEFAULT(Flags.DEFAULT), 360 STRICTFP(Flags.STRICTFP), 361 BRIDGE(Flags.BRIDGE), 362 SYNTHETIC(Flags.SYNTHETIC), 363 ANNOTATION(Flags.ANNOTATION), 364 DEPRECATED(Flags.DEPRECATED), 365 HASINIT(Flags.HASINIT), 366 BLOCK(Flags.BLOCK), 367 ENUM(Flags.ENUM), 368 MANDATED(Flags.MANDATED), 369 IPROXY(Flags.IPROXY), 370 NOOUTERTHIS(Flags.NOOUTERTHIS), 371 EXISTS(Flags.EXISTS), 372 COMPOUND(Flags.COMPOUND), 373 CLASS_SEEN(Flags.CLASS_SEEN), 374 SOURCE_SEEN(Flags.SOURCE_SEEN), 375 LOCKED(Flags.LOCKED), 376 UNATTRIBUTED(Flags.UNATTRIBUTED), 377 ANONCONSTR(Flags.ANONCONSTR), 378 ACYCLIC(Flags.ACYCLIC), 379 PARAMETER(Flags.PARAMETER), 380 VARARGS(Flags.VARARGS), 381 ACYCLIC_ANN(Flags.ACYCLIC_ANN), 382 GENERATEDCONSTR(Flags.GENERATEDCONSTR), 383 HYPOTHETICAL(Flags.HYPOTHETICAL), 384 PROPRIETARY(Flags.PROPRIETARY), 385 UNION(Flags.UNION), 386 OVERRIDE_BRIDGE(Flags.OVERRIDE_BRIDGE), 387 EFFECTIVELY_FINAL(Flags.EFFECTIVELY_FINAL), 388 CLASH(Flags.CLASH), 389 AUXILIARY(Flags.AUXILIARY), 390 NOT_IN_PROFILE(Flags.NOT_IN_PROFILE), 391 BAD_OVERRIDE(Flags.BAD_OVERRIDE), 392 SIGNATURE_POLYMORPHIC(Flags.SIGNATURE_POLYMORPHIC), 393 THROWS(Flags.THROWS), 394 LAMBDA_METHOD(Flags.LAMBDA_METHOD), 395 TYPE_TRANSLATED(Flags.TYPE_TRANSLATED); 396 Flag(long flag)397 Flag(long flag) { 398 this.value = flag; 399 this.lowercaseName = StringUtils.toLowerCase(name()); 400 } 401 402 @Override toString()403 public String toString() { 404 return lowercaseName; 405 } 406 407 final long value; 408 final String lowercaseName; 409 } 410 411 } 412