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 * Returns the elements of an enum class or null if the 117 * Class object does not represent an enum type; 118 * the result is uncloned, cached, and shared by all callers. 119 */ 120 <E extends Enum<E>> E[] getEnumConstantsShared(Class<E> klass); 121 122 /** 123 * Set current thread's blocker field. 124 */ 125 void blockedOn(Interruptible b); 126 127 /** 128 * Registers a shutdown hook. 129 * 130 * It is expected that this method with registerShutdownInProgress=true 131 * is only used to register DeleteOnExitHook since the first file 132 * may be added to the delete on exit list by the application shutdown 133 * hooks. 134 * 135 * @param slot the slot in the shutdown hook array, whose element 136 * will be invoked in order during shutdown 137 * @param registerShutdownInProgress true to allow the hook 138 * to be registered even if the shutdown is in progress. 139 * @param hook the hook to be registered 140 * 141 * @throws IllegalStateException if shutdown is in progress and 142 * the slot is not valid to register. 143 */ 144 void registerShutdownHook(int slot, boolean registerShutdownInProgress, Runnable hook); 145 146 /** 147 * Invokes the finalize method of the given object. 148 */ 149 void invokeFinalize(Object o) throws Throwable; 150 151 /** 152 * Returns the ConcurrentHashMap used as a storage for ClassLoaderValue(s) 153 * associated with the given class loader, creating it if it doesn't already exist. 154 */ 155 ConcurrentHashMap<?, ?> createOrGetClassLoaderValueMap(ClassLoader cl); 156 157 /** 158 * Defines a class with the given name to a class loader. 159 */ 160 Class<?> defineClass(ClassLoader cl, String name, byte[] b, ProtectionDomain pd, String source); 161 162 /** 163 * Defines a class with the given name to a class loader with 164 * the given flags and class data. 165 * 166 * @see java.lang.invoke.MethodHandles.Lookup#defineClass 167 */ 168 Class<?> defineClass(ClassLoader cl, Class<?> lookup, String name, byte[] b, ProtectionDomain pd, boolean initialize, int flags, Object classData); 169 170 /** 171 * Returns a class loaded by the bootstrap class loader. 172 */ 173 Class<?> findBootstrapClassOrNull(String name); 174 175 /** 176 * Define a Package of the given name and module by the given class loader. 177 */ 178 Package definePackage(ClassLoader cl, String name, Module module); 179 180 /** 181 * Defines a new module to the Java virtual machine. The module 182 * is defined to the given class loader. 183 * 184 * The URI is for information purposes only, it can be {@code null}. 185 */ 186 Module defineModule(ClassLoader loader, ModuleDescriptor descriptor, URI uri); 187 188 /** 189 * Defines the unnamed module for the given class loader. 190 */ 191 Module defineUnnamedModule(ClassLoader loader); 192 193 /** 194 * Updates the readability so that module m1 reads m2. The new read edge 195 * does not result in a strong reference to m2 (m2 can be GC'ed). 196 * 197 * This method is the same as m1.addReads(m2) but without a permission check. 198 */ 199 void addReads(Module m1, Module m2); 200 201 /** 202 * Updates module m to read all unnamed modules. 203 */ 204 void addReadsAllUnnamed(Module m); 205 206 /** 207 * Updates module m1 to export a package unconditionally. 208 */ 209 void addExports(Module m1, String pkg); 210 211 /** 212 * Updates module m1 to export a package to module m2. The export does 213 * not result in a strong reference to m2 (m2 can be GC'ed). 214 */ 215 void addExports(Module m1, String pkg, Module m2); 216 217 /** 218 * Updates a module m to export a package to all unnamed modules. 219 */ 220 void addExportsToAllUnnamed(Module m, String pkg); 221 222 /** 223 * Updates module m1 to open a package to module m2. Opening the 224 * package does not result in a strong reference to m2 (m2 can be GC'ed). 225 */ 226 void addOpens(Module m1, String pkg, Module m2); 227 228 /** 229 * Updates module m to open a package to all unnamed modules. 230 */ 231 void addOpensToAllUnnamed(Module m, String pkg); 232 233 /** 234 * Updates module m to use a service. 235 */ 236 void addUses(Module m, Class<?> service); 237 238 /** 239 * Returns true if module m reflectively exports a package to other 240 */ 241 boolean isReflectivelyExported(Module module, String pn, Module other); 242 243 /** 244 * Returns true if module m reflectively opens a package to other 245 */ 246 boolean isReflectivelyOpened(Module module, String pn, Module other); 247 248 /** 249 * Updates module m to allow access to restricted methods. 250 */ 251 Module addEnableNativeAccess(Module m); 252 253 /** 254 * Updates module named {@code name} in layer {@code layer} to allow access to restricted methods. 255 * Returns true iff the given module exists in the given layer. 256 */ 257 boolean addEnableNativeAccess(ModuleLayer layer, String name); 258 259 /** 260 * Updates all unnamed modules to allow access to restricted methods. 261 */ 262 void addEnableNativeAccessToAllUnnamed(); 263 264 /** 265 * Ensure that the given module has native access. If not, warn or throw exception depending on the configuration. 266 * @param m the module in which native access occurred 267 * @param owner the owner of the restricted method being called (or the JNI method being bound) 268 * @param methodName the name of the restricted method being called (or the JNI method being bound) 269 * @param currentClass the class calling the restricted method (for JNI, this is the same as {@code owner}) 270 * @param jni {@code true}, if this event is related to a JNI method being bound 271 */ 272 void ensureNativeAccess(Module m, Class<?> owner, String methodName, Class<?> currentClass, boolean jni); 273 274 /** 275 * Returns the ServicesCatalog for the given Layer. 276 */ 277 ServicesCatalog getServicesCatalog(ModuleLayer layer); 278 279 /** 280 * Record that this layer has at least one module defined to the given 281 * class loader. 282 */ 283 void bindToLoader(ModuleLayer layer, ClassLoader loader); 284 285 /** 286 * Returns an ordered stream of layers. The first element is the 287 * given layer, the remaining elements are its parents, in DFS order. 288 */ 289 Stream<ModuleLayer> layers(ModuleLayer layer); 290 291 /** 292 * Returns a stream of the layers that have modules defined to the 293 * given class loader. 294 */ 295 Stream<ModuleLayer> layers(ClassLoader loader); 296 297 /** 298 * Count the number of leading positive bytes in the range. 299 */ 300 int countPositives(byte[] ba, int off, int len); 301 302 /** 303 * Count the number of leading non-zero ascii chars in the String. 304 */ 305 int countNonZeroAscii(String s); 306 307 /** 308 * Constructs a new {@code String} by decoding the specified subarray of 309 * bytes using the specified {@linkplain java.nio.charset.Charset charset}. 310 * 311 * The caller of this method shall relinquish and transfer the ownership of 312 * the byte array to the callee since the later will not make a copy. 313 * 314 * @param bytes the byte array source 315 * @param cs the Charset 316 * @return the newly created string 317 * @throws CharacterCodingException for malformed or unmappable bytes 318 */ 319 String newStringNoRepl(byte[] bytes, Charset cs) throws CharacterCodingException; 320 321 /** 322 * Encode the given string into a sequence of bytes using the specified Charset. 323 * 324 * This method avoids copying the String's internal representation if the input 325 * is ASCII. 326 * 327 * This method throws CharacterCodingException instead of replacing when 328 * malformed input or unmappable characters are encountered. 329 * 330 * @param s the string to encode 331 * @param cs the charset 332 * @return the encoded bytes 333 * @throws CharacterCodingException for malformed input or unmappable characters 334 */ 335 byte[] getBytesNoRepl(String s, Charset cs) throws CharacterCodingException; 336 337 /** 338 * Returns a new string by decoding from the given utf8 bytes array. 339 * 340 * @param off the index of the first byte to decode 341 * @param len the number of bytes to decode 342 * @return the newly created string 343 * @throws IllegalArgumentException for malformed or unmappable bytes. 344 */ 345 String newStringUTF8NoRepl(byte[] bytes, int off, int len); 346 347 /** 348 * Get the char at index in a byte[] in internal UTF-16 representation, 349 * with no bounds checks. 350 * 351 * @param bytes the UTF-16 encoded bytes 352 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1) 353 * @return the char value 354 */ 355 char getUTF16Char(byte[] bytes, int index); 356 357 /** 358 * Put the char at index in a byte[] in internal UTF-16 representation, 359 * with no bounds checks. 360 * 361 * @param bytes the UTF-16 encoded bytes 362 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1) 363 */ 364 void putCharUTF16(byte[] bytes, int index, int ch); 365 366 /** 367 * Encode the given string into a sequence of bytes using utf8. 368 * 369 * @param s the string to encode 370 * @return the encoded bytes in utf8 371 * @throws IllegalArgumentException for malformed surrogates 372 */ 373 byte[] getBytesUTF8NoRepl(String s); 374 375 /** 376 * Inflated copy from byte[] to char[], as defined by StringLatin1.inflate 377 */ 378 void inflateBytesToChars(byte[] src, int srcOff, char[] dst, int dstOff, int len); 379 380 /** 381 * Decodes ASCII from the source byte array into the destination 382 * char array. 383 * 384 * @return the number of bytes successfully decoded, at most len 385 */ 386 int decodeASCII(byte[] src, int srcOff, char[] dst, int dstOff, int len); 387 388 /** 389 * Returns the initial `System.in` to determine if it is replaced 390 * with `System.setIn(newIn)` method 391 */ 392 InputStream initialSystemIn(); 393 394 /** 395 * Returns the initial value of System.err. 396 */ 397 PrintStream initialSystemErr(); 398 399 /** 400 * Encodes ASCII codepoints as possible from the source array into 401 * the destination byte array, assuming that the encoding is ASCII 402 * compatible 403 * 404 * @return the number of bytes successfully encoded, or 0 if none 405 */ 406 int encodeASCII(char[] src, int srcOff, byte[] dst, int dstOff, int len); 407 408 /** 409 * Set the cause of Throwable 410 * @param cause set t's cause to new value 411 */ 412 void setCause(Throwable t, Throwable cause); 413 414 /** 415 * Get protection domain of the given Class 416 */ 417 ProtectionDomain protectionDomain(Class<?> c); 418 419 /** 420 * Get a method handle of string concat helper method 421 */ 422 MethodHandle stringConcatHelper(String name, MethodType methodType); 423 424 /** 425 * Get the string concat initial coder 426 */ 427 long stringConcatInitialCoder(); 428 429 /** 430 * Update lengthCoder for constant 431 */ 432 long stringConcatMix(long lengthCoder, String constant); 433 434 /** 435 * Mix value length and coder into current length and coder. 436 */ 437 long stringConcatMix(long lengthCoder, char value); 438 439 Object stringConcat1(String[] constants); 440 441 /** 442 * Get the string initial coder, When COMPACT_STRINGS is on, it returns 0, and when it is off, it returns 1. 443 */ 444 byte stringInitCoder(); 445 446 /** 447 * Get the Coder of String, which is used by StringConcatFactory to calculate the initCoder of constants 448 */ 449 byte stringCoder(String str); 450 451 /** 452 * Join strings 453 */ 454 String join(String prefix, String suffix, String delimiter, String[] elements, int size); 455 456 /** 457 * Concatenation of prefix and suffix characters to a String for early bootstrap 458 */ 459 String concat(String prefix, Object value, String suffix); 460 461 /* 462 * Get the class data associated with the given class. 463 * @param c the class 464 * @see java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...) 465 */ 466 Object classData(Class<?> c); 467 468 /** 469 * Returns the {@link NativeLibraries} object associated with the provided class loader. 470 * This is used by {@link SymbolLookup#loaderLookup()}. 471 */ 472 NativeLibraries nativeLibrariesFor(ClassLoader loader); 473 474 /** 475 * Returns an array of all platform threads. 476 */ 477 Thread[] getAllThreads(); 478 479 /** 480 * Returns the ThreadContainer for a thread, may be null. 481 */ 482 ThreadContainer threadContainer(Thread thread); 483 484 /** 485 * Starts a thread in the given ThreadContainer. 486 */ 487 void start(Thread thread, ThreadContainer container); 488 489 /** 490 * Returns the top of the given thread's stackable scope stack. 491 */ 492 StackableScope headStackableScope(Thread thread); 493 494 /** 495 * Sets the top of the current thread's stackable scope stack. 496 */ 497 void setHeadStackableScope(StackableScope scope); 498 499 /** 500 * Returns the Thread object for the current platform thread. If the 501 * current thread is a virtual thread then this method returns the carrier. 502 */ 503 Thread currentCarrierThread(); 504 505 /** 506 * Returns the given virtual thread's carrier or {@code null} if not mounted. 507 * @throws UnsupportedOperationException if the thread is not a virtual thread 508 */ 509 Thread getCarrierThread(Thread thread); 510 511 /** 512 * Returns the given virtual thread's internal state. 513 * @throws UnsupportedOperationException if the thread is not a virtual thread 514 */ 515 int getInternalState(Thread thread); 516 517 /** 518 * Returns the value of the current carrier thread's copy of a thread-local. 519 */ 520 <T> T getCarrierThreadLocal(CarrierThreadLocal<T> local); 521 522 /** 523 * Sets the value of the current carrier thread's copy of a thread-local. 524 */ 525 <T> void setCarrierThreadLocal(CarrierThreadLocal<T> local, T value); 526 527 /** 528 * Removes the value of the current carrier thread's copy of a thread-local. 529 */ 530 void removeCarrierThreadLocal(CarrierThreadLocal<?> local); 531 532 /** 533 * Returns {@code true} if there is a value in the current carrier thread's copy of 534 * thread-local, even if that values is {@code null}. 535 */ 536 boolean isCarrierThreadLocalPresent(CarrierThreadLocal<?> local); 537 538 /** 539 * Returns the current thread's scoped values cache 540 */ 541 Object[] scopedValueCache(); 542 543 /** 544 * Sets the current thread's scoped values cache 545 */ 546 void setScopedValueCache(Object[] cache); 547 548 /** 549 * Return the current thread's scoped value bindings. 550 */ 551 Object scopedValueBindings(); 552 553 /** 554 * Returns the innermost mounted continuation 555 */ 556 Continuation getContinuation(Thread thread); 557 558 /** 559 * Sets the innermost mounted continuation 560 */ 561 void setContinuation(Thread thread, Continuation continuation); 562 563 /** 564 * The ContinuationScope of virtual thread continuations 565 */ 566 ContinuationScope virtualThreadContinuationScope(); 567 568 /** 569 * Parks the current virtual thread. 570 * @throws WrongThreadException if the current thread is not a virtual thread 571 */ 572 void parkVirtualThread(); 573 574 /** 575 * Parks the current virtual thread for up to the given waiting time. 576 * @param nanos the maximum number of nanoseconds to wait 577 * @throws WrongThreadException if the current thread is not a virtual thread 578 */ 579 void parkVirtualThread(long nanos); 580 581 /** 582 * Re-enables a virtual thread for scheduling. If the thread was parked then 583 * it will be unblocked, otherwise its next attempt to park will not block 584 * @param thread the virtual thread to unpark 585 * @throws IllegalArgumentException if the thread is not a virtual thread 586 * @throws RejectedExecutionException if the scheduler cannot accept a task 587 */ 588 void unparkVirtualThread(Thread thread); 589 590 /** 591 * Returns the virtual thread default scheduler. 592 */ 593 Executor virtualThreadDefaultScheduler(); 594 595 /** 596 * Creates a new StackWalker 597 */ 598 StackWalker newStackWalkerInstance(Set<StackWalker.Option> options, 599 ContinuationScope contScope, 600 Continuation continuation); 601 /** 602 * Returns '<loader-name>' @<id> if classloader has a name 603 * explicitly set otherwise <qualified-class-name> @<id> 604 */ 605 String getLoaderNameID(ClassLoader loader); 606 607 /** 608 * Copy the string bytes to an existing segment, avoiding intermediate copies. 609 */ 610 void copyToSegmentRaw(String string, MemorySegment segment, long offset); 611 612 /** 613 * Are the string bytes compatible with the given charset? 614 */ 615 boolean bytesCompatible(String string, Charset charset); 616 }