1 /* 2 * Copyright (c) 2003, 2025, 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 jdk.internal.access; 27 28 import java.io.InputStream; 29 import java.io.PrintStream; 30 import java.lang.annotation.Annotation; 31 import java.lang.foreign.MemorySegment; 32 import java.lang.foreign.SymbolLookup; 33 import java.lang.invoke.MethodHandle; 34 import java.lang.invoke.MethodType; 35 import java.lang.module.ModuleDescriptor; 36 import java.lang.reflect.Executable; 37 import java.lang.reflect.Method; 38 import java.net.URI; 39 import java.nio.charset.CharacterCodingException; 40 import java.nio.charset.Charset; 41 import java.security.ProtectionDomain; 42 import java.util.List; 43 import java.util.Map; 44 import java.util.Set; 45 import java.util.concurrent.ConcurrentHashMap; 46 import java.util.concurrent.Executor; 47 import java.util.concurrent.RejectedExecutionException; 48 import java.util.stream.Stream; 49 50 import jdk.internal.loader.NativeLibraries; 51 import jdk.internal.misc.CarrierThreadLocal; 52 import jdk.internal.module.ServicesCatalog; 53 import jdk.internal.reflect.ConstantPool; 54 import jdk.internal.vm.Continuation; 55 import jdk.internal.vm.ContinuationScope; 56 import jdk.internal.vm.StackableScope; 57 import jdk.internal.vm.ThreadContainer; 58 import sun.reflect.annotation.AnnotationType; 59 import sun.nio.ch.Interruptible; 60 61 public interface JavaLangAccess { 62 63 /** 64 * Returns the list of {@code Method} objects for the declared public 65 * methods of this class or interface that have the specified method name 66 * and parameter types. 67 */ 68 List<Method> getDeclaredPublicMethods(Class<?> klass, String name, Class<?>... parameterTypes); 69 70 /** 71 * Return most specific method that matches name and parameterTypes. 72 */ 73 Method findMethod(Class<?> klass, boolean publicOnly, String name, Class<?>... parameterTypes); 74 75 /** 76 * Return the constant pool for a class. 77 */ 78 ConstantPool getConstantPool(Class<?> klass); 79 80 /** 81 * Compare-And-Set the AnnotationType instance corresponding to this class. 82 * (This method only applies to annotation types.) 83 */ 84 boolean casAnnotationType(Class<?> klass, AnnotationType oldType, AnnotationType newType); 85 86 /** 87 * Get the AnnotationType instance corresponding to this class. 88 * (This method only applies to annotation types.) 89 */ 90 AnnotationType getAnnotationType(Class<?> klass); 91 92 /** 93 * Get the declared annotations for a given class, indexed by their types. 94 */ 95 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap(Class<?> klass); 96 97 /** 98 * Get the array of bytes that is the class-file representation 99 * of this Class' annotations. 100 */ 101 byte[] getRawClassAnnotations(Class<?> klass); 102 103 /** 104 * Get the array of bytes that is the class-file representation 105 * of this Class' type annotations. 106 */ 107 byte[] getRawClassTypeAnnotations(Class<?> klass); 108 109 /** 110 * Get the array of bytes that is the class-file representation 111 * of this Executable's type annotations. 112 */ 113 byte[] getRawExecutableTypeAnnotations(Executable executable); 114 115 /** 116 * Get the int value of the Class's class-file access flags. 117 */ 118 int getClassFileAccessFlags(Class<?> klass); 119 120 /** 121 * Returns the elements of an enum class or null if the 122 * Class object does not represent an enum type; 123 * the result is uncloned, cached, and shared by all callers. 124 */ 125 <E extends Enum<E>> E[] getEnumConstantsShared(Class<E> klass); 126 127 /** 128 * Returns the big-endian packed minor-major version of the class file 129 * of this class. 130 */ 131 int classFileVersion(Class<?> clazz); 132 133 /** 134 * Set current thread's blocker field. 135 */ 136 void blockedOn(Interruptible b); 137 138 /** 139 * Registers a shutdown hook. 140 * 141 * It is expected that this method with registerShutdownInProgress=true 142 * is only used to register DeleteOnExitHook since the first file 143 * may be added to the delete on exit list by the application shutdown 144 * hooks. 145 * 146 * @param slot the slot in the shutdown hook array, whose element 147 * will be invoked in order during shutdown 148 * @param registerShutdownInProgress true to allow the hook 149 * to be registered even if the shutdown is in progress. 150 * @param hook the hook to be registered 151 * 152 * @throws IllegalStateException if shutdown is in progress and 153 * the slot is not valid to register. 154 */ 155 void registerShutdownHook(int slot, boolean registerShutdownInProgress, Runnable hook); 156 157 /** 158 * Invokes the finalize method of the given object. 159 */ 160 void invokeFinalize(Object o) throws Throwable; 161 162 /** 163 * Returns the ConcurrentHashMap used as a storage for ClassLoaderValue(s) 164 * associated with the given class loader, creating it if it doesn't already exist. 165 */ 166 ConcurrentHashMap<?, ?> createOrGetClassLoaderValueMap(ClassLoader cl); 167 168 /** 169 * Defines a class with the given name to a class loader. 170 */ 171 Class<?> defineClass(ClassLoader cl, String name, byte[] b, ProtectionDomain pd, String source); 172 173 /** 174 * Defines a class with the given name to a class loader with 175 * the given flags and class data. 176 * 177 * @see java.lang.invoke.MethodHandles.Lookup#defineClass 178 */ 179 Class<?> defineClass(ClassLoader cl, Class<?> lookup, String name, byte[] b, ProtectionDomain pd, boolean initialize, int flags, Object classData); 180 181 /** 182 * Returns a class loaded by the bootstrap class loader. 183 */ 184 Class<?> findBootstrapClassOrNull(String name); 185 186 /** 187 * Define a Package of the given name and module by the given class loader. 188 */ 189 Package definePackage(ClassLoader cl, String name, Module module); 190 191 /** 192 * Defines a new module to the Java virtual machine. The module 193 * is defined to the given class loader. 194 * 195 * The URI is for information purposes only, it can be {@code null}. 196 */ 197 Module defineModule(ClassLoader loader, ModuleDescriptor descriptor, URI uri); 198 199 /** 200 * Defines the unnamed module for the given class loader. 201 */ 202 Module defineUnnamedModule(ClassLoader loader); 203 204 /** 205 * Updates the readability so that module m1 reads m2. The new read edge 206 * does not result in a strong reference to m2 (m2 can be GC'ed). 207 * 208 * This method is the same as m1.addReads(m2) but without a permission check. 209 */ 210 void addReads(Module m1, Module m2); 211 212 /** 213 * Updates module m to read all unnamed modules. 214 */ 215 void addReadsAllUnnamed(Module m); 216 217 /** 218 * Updates module m1 to export a package unconditionally. 219 */ 220 void addExports(Module m1, String pkg); 221 222 /** 223 * Updates module m1 to export a package to module m2. The export does 224 * not result in a strong reference to m2 (m2 can be GC'ed). 225 */ 226 void addExports(Module m1, String pkg, Module m2); 227 228 /** 229 * Updates a module m to export a package to all unnamed modules. 230 */ 231 void addExportsToAllUnnamed(Module m, String pkg); 232 233 /** 234 * Updates module m1 to open a package to module m2. Opening the 235 * package does not result in a strong reference to m2 (m2 can be GC'ed). 236 */ 237 void addOpens(Module m1, String pkg, Module m2); 238 239 /** 240 * Updates module m to open a package to all unnamed modules. 241 */ 242 void addOpensToAllUnnamed(Module m, String pkg); 243 244 /** 245 * Updates module m to use a service. 246 */ 247 void addUses(Module m, Class<?> service); 248 249 /** 250 * Returns true if module m reflectively exports a package to other 251 */ 252 boolean isReflectivelyExported(Module module, String pn, Module other); 253 254 /** 255 * Returns true if module m reflectively opens a package to other 256 */ 257 boolean isReflectivelyOpened(Module module, String pn, Module other); 258 259 /** 260 * Updates module m to allow access to restricted methods. 261 */ 262 Module addEnableNativeAccess(Module m); 263 264 /** 265 * Updates module named {@code name} in layer {@code layer} to allow access to restricted methods. 266 * Returns true iff the given module exists in the given layer. 267 */ 268 boolean addEnableNativeAccess(ModuleLayer layer, String name); 269 270 /** 271 * Updates all unnamed modules to allow access to restricted methods. 272 */ 273 void addEnableNativeAccessToAllUnnamed(); 274 275 /** 276 * Ensure that the given module has native access. If not, warn or throw exception depending on the configuration. 277 * @param m the module in which native access occurred 278 * @param owner the owner of the restricted method being called (or the JNI method being bound) 279 * @param methodName the name of the restricted method being called (or the JNI method being bound) 280 * @param currentClass the class calling the restricted method (for JNI, this is the same as {@code owner}) 281 * @param jni {@code true}, if this event is related to a JNI method being bound 282 */ 283 void ensureNativeAccess(Module m, Class<?> owner, String methodName, Class<?> currentClass, boolean jni); 284 285 /** 286 * Returns the ServicesCatalog for the given Layer. 287 */ 288 ServicesCatalog getServicesCatalog(ModuleLayer layer); 289 290 /** 291 * Record that this layer has at least one module defined to the given 292 * class loader. 293 */ 294 void bindToLoader(ModuleLayer layer, ClassLoader loader); 295 296 /** 297 * Returns an ordered stream of layers. The first element is the 298 * given layer, the remaining elements are its parents, in DFS order. 299 */ 300 Stream<ModuleLayer> layers(ModuleLayer layer); 301 302 /** 303 * Returns a stream of the layers that have modules defined to the 304 * given class loader. 305 */ 306 Stream<ModuleLayer> layers(ClassLoader loader); 307 308 /** 309 * Count the number of leading positive bytes in the range. 310 * 311 * @implSpec Implementations of this method must perform bounds checks. 312 */ 313 int countPositives(byte[] ba, int off, int len); 314 315 /** 316 * Count the number of leading non-zero ascii chars in the String. 317 */ 318 int countNonZeroAscii(String s); 319 320 /** 321 * Constructs a new {@code String} with the supplied Latin1 bytes. 322 * <p> 323 * <b>WARNING: The caller of this method shall relinquish and transfer the 324 * ownership of the byte array to the callee</b>, since the latter will not 325 * make a copy. 326 * 327 * @param bytes the byte array source 328 * @return the newly created string 329 */ 330 String uncheckedNewStringWithLatin1Bytes(byte[] bytes); 331 332 /** 333 * Constructs a new {@code String} by decoding the specified byte array 334 * using the specified {@code Charset}. 335 * <p> 336 * <b>WARNING: The caller of this method shall relinquish and transfer the 337 * ownership of the byte array to the callee</b>, since the latter will not 338 * make a copy. 339 * 340 * @param bytes the byte array source 341 * @param cs the Charset 342 * @return the newly created string 343 * @throws CharacterCodingException for malformed or unmappable bytes 344 * @throws NullPointerException If {@code bytes} or {@code cs} is null 345 */ 346 String uncheckedNewStringOrThrow(byte[] bytes, Charset cs) throws CharacterCodingException; 347 348 /** 349 * {@return the sequence of bytes obtained by encoding the given string in 350 * the specified {@code Charset}} 351 * <p> 352 * <b>WARNING: This method returns the {@code byte[]} backing the provided 353 * {@code String}, if the input is ASCII. Hence, the returned byte array 354 * must not be modified.</b> 355 * 356 * @param s the string to encode 357 * @param cs the charset 358 * @throws NullPointerException If {@code s} or {@code cs} is null 359 * @throws CharacterCodingException for malformed input or unmappable characters 360 */ 361 byte[] uncheckedGetBytesOrThrow(String s, Charset cs) throws CharacterCodingException; 362 363 /** 364 * Get the {@code char} at {@code index} in a {@code byte[]} in internal 365 * UTF-16 representation. 366 * <p> 367 * <b>WARNING: This method does not perform any bound checks.</b> 368 * 369 * @param bytes the UTF-16 encoded bytes 370 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1) 371 * @return the char value 372 */ 373 char uncheckedGetUTF16Char(byte[] bytes, int index); 374 375 /** 376 * Put the {@code ch} at {@code index} in a {@code byte[]} in internal 377 * UTF-16 representation. 378 * <p> 379 * <b>WARNING: This method does not perform any bound checks.</b> 380 * 381 * @param bytes the UTF-16 encoded bytes 382 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1) 383 */ 384 void uncheckedPutCharUTF16(byte[] bytes, int index, int ch); 385 386 /** 387 * {@return the sequence of bytes obtained by encoding the given string in UTF-8} 388 * 389 * @param s the string to encode 390 * @throws NullPointerException If {@code s} is null 391 * @throws CharacterCodingException For malformed input or unmappable characters 392 */ 393 byte[] getBytesUTF8OrThrow(String s) throws CharacterCodingException; 394 395 /** 396 * Inflated copy from {@code byte[]} to {@code char[]}, as defined by 397 * {@code StringLatin1.inflate}. 398 * 399 * @implSpec Implementations of this method must perform bounds checks. 400 */ 401 void inflateBytesToChars(byte[] src, int srcOff, char[] dst, int dstOff, int len); 402 403 /** 404 * Decodes ASCII from the source byte array into the destination 405 * char array. 406 * 407 * @implSpec Implementations of this method must perform bounds checks. 408 * 409 * @return the number of bytes successfully decoded, at most len 410 */ 411 int decodeASCII(byte[] src, int srcOff, char[] dst, int dstOff, int len); 412 413 /** 414 * Returns the initial `System.in` to determine if it is replaced 415 * with `System.setIn(newIn)` method 416 */ 417 InputStream initialSystemIn(); 418 419 /** 420 * Returns the initial value of System.err. 421 */ 422 PrintStream initialSystemErr(); 423 424 /** 425 * Encodes as many ASCII codepoints as possible from the source 426 * character array into the destination byte array, assuming that 427 * the encoding is ASCII compatible. 428 * 429 * @param sa the source character array 430 * @param sp the index of the source array to start reading from 431 * @param da the target byte array 432 * @param dp the index of the target array to start writing to 433 * @param len the total number of characters to be encoded 434 * @return the total number of characters successfully encoded 435 * @throws NullPointerException if any of the provided arrays is null 436 */ 437 int encodeASCII(char[] sa, int sp, byte[] da, int dp, int len); 438 439 /** 440 * Set the cause of Throwable 441 * @param cause set t's cause to new value 442 */ 443 void setCause(Throwable t, Throwable cause); 444 445 /** 446 * Get protection domain of the given Class 447 */ 448 ProtectionDomain protectionDomain(Class<?> c); 449 450 /** 451 * Get a method handle of string concat helper method 452 */ 453 MethodHandle stringConcatHelper(String name, MethodType methodType); 454 455 /** 456 * Get the string concat initial coder 457 */ 458 long stringConcatInitialCoder(); 459 460 /** 461 * Update lengthCoder for constant 462 */ 463 long stringConcatMix(long lengthCoder, String constant); 464 465 /** 466 * Mix value length and coder into current length and coder. 467 */ 468 long stringConcatMix(long lengthCoder, char value); 469 470 /** 471 * Creates helper for string concatenation. 472 * <p> 473 * <b>WARNING: The caller of this method shall relinquish and transfer the 474 * ownership of the string array to the callee</b>, since the latter will not 475 * make a copy. 476 */ 477 Object uncheckedStringConcat1(String[] constants); 478 479 /** 480 * Get the string initial coder, When COMPACT_STRINGS is on, it returns 0, and when it is off, it returns 1. 481 */ 482 byte stringInitCoder(); 483 484 /** 485 * Get the Coder of String, which is used by StringConcatFactory to calculate the initCoder of constants 486 */ 487 byte stringCoder(String str); 488 489 /** 490 * Join strings 491 */ 492 String join(String prefix, String suffix, String delimiter, String[] elements, int size); 493 494 /** 495 * Concatenation of prefix and suffix characters to a String for early bootstrap 496 */ 497 String concat(String prefix, Object value, String suffix); 498 499 /* 500 * Get the class data associated with the given class. 501 * @param c the class 502 * @see java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...) 503 */ 504 Object classData(Class<?> c); 505 506 /** 507 * Returns the {@link NativeLibraries} object associated with the provided class loader. 508 * This is used by {@link SymbolLookup#loaderLookup()}. 509 */ 510 NativeLibraries nativeLibrariesFor(ClassLoader loader); 511 512 /** 513 * Returns an array of all platform threads. 514 */ 515 Thread[] getAllThreads(); 516 517 /** 518 * Returns the ThreadContainer for a thread, may be null. 519 */ 520 ThreadContainer threadContainer(Thread thread); 521 522 /** 523 * Starts a thread in the given ThreadContainer. 524 */ 525 void start(Thread thread, ThreadContainer container); 526 527 /** 528 * Returns the top of the given thread's stackable scope stack. 529 */ 530 StackableScope headStackableScope(Thread thread); 531 532 /** 533 * Sets the top of the current thread's stackable scope stack. 534 */ 535 void setHeadStackableScope(StackableScope scope); 536 537 /** 538 * Returns the Thread object for the current platform thread. If the 539 * current thread is a virtual thread then this method returns the carrier. 540 */ 541 Thread currentCarrierThread(); 542 543 /** 544 * Returns the value of the current carrier thread's copy of a thread-local. 545 */ 546 <T> T getCarrierThreadLocal(CarrierThreadLocal<T> local); 547 548 /** 549 * Sets the value of the current carrier thread's copy of a thread-local. 550 */ 551 <T> void setCarrierThreadLocal(CarrierThreadLocal<T> local, T value); 552 553 /** 554 * Removes the value of the current carrier thread's copy of a thread-local. 555 */ 556 void removeCarrierThreadLocal(CarrierThreadLocal<?> local); 557 558 /** 559 * Returns the current thread's scoped values cache 560 */ 561 Object[] scopedValueCache(); 562 563 /** 564 * Sets the current thread's scoped values cache 565 */ 566 void setScopedValueCache(Object[] cache); 567 568 /** 569 * Return the current thread's scoped value bindings. 570 */ 571 Object scopedValueBindings(); 572 573 /** 574 * Returns the innermost mounted continuation 575 */ 576 Continuation getContinuation(Thread thread); 577 578 /** 579 * Sets the innermost mounted continuation 580 */ 581 void setContinuation(Thread thread, Continuation continuation); 582 583 /** 584 * The ContinuationScope of virtual thread continuations 585 */ 586 ContinuationScope virtualThreadContinuationScope(); 587 588 /** 589 * Parks the current virtual thread. 590 * @throws WrongThreadException if the current thread is not a virtual thread 591 */ 592 void parkVirtualThread(); 593 594 /** 595 * Parks the current virtual thread for up to the given waiting time. 596 * @param nanos the maximum number of nanoseconds to wait 597 * @throws WrongThreadException if the current thread is not a virtual thread 598 */ 599 void parkVirtualThread(long nanos); 600 601 /** 602 * Re-enables a virtual thread for scheduling. If the thread was parked then 603 * it will be unblocked, otherwise its next attempt to park will not block 604 * @param thread the virtual thread to unpark 605 * @throws IllegalArgumentException if the thread is not a virtual thread 606 * @throws RejectedExecutionException if the scheduler cannot accept a task 607 */ 608 void unparkVirtualThread(Thread thread); 609 610 /** 611 * Returns the virtual thread default scheduler. 612 */ 613 Executor virtualThreadDefaultScheduler(); 614 615 /** 616 * Creates a new StackWalker 617 */ 618 StackWalker newStackWalkerInstance(Set<StackWalker.Option> options, 619 ContinuationScope contScope, 620 Continuation continuation); 621 /** 622 * Returns '<loader-name>' @<id> if classloader has a name 623 * explicitly set otherwise <qualified-class-name> @<id> 624 */ 625 String getLoaderNameID(ClassLoader loader); 626 627 /** 628 * Copy the string bytes to an existing segment, avoiding intermediate copies. 629 */ 630 void copyToSegmentRaw(String string, MemorySegment segment, long offset); 631 632 /** 633 * Are the string bytes compatible with the given charset? 634 */ 635 boolean bytesCompatible(String string, Charset charset); 636 }