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.RejectedExecutionException;
47 import java.util.function.Supplier;
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 {@linkplain java.nio.charset.Charset 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 */
345 String uncheckedNewStringNoRepl(byte[] bytes, Charset cs) throws CharacterCodingException;
346
347 /**
348 * Encode the given string into a sequence of bytes using the specified
349 * {@linkplain java.nio.charset.Charset charset}.
350 * <p>
351 * <b>WARNING: This method returns the {@code byte[]} backing the provided
352 * {@code String}, if the input is ASCII. Hence, the returned byte array
353 * must not be modified.</b>
354 * <p>
355 * This method throws {@code CharacterCodingException} instead of replacing
356 * when malformed input or unmappable characters are encountered.
357 *
358 * @param s the string to encode
359 * @param cs the charset
360 * @return the encoded bytes
361 * @throws CharacterCodingException for malformed input or unmappable characters
362 */
363 byte[] uncheckedGetBytesNoRepl(String s, Charset cs) throws CharacterCodingException;
364
365 /**
366 * Get the {@code char} at {@code index} in a {@code byte[]} in internal
367 * UTF-16 representation.
368 * <p>
369 * <b>WARNING: This method does not perform any bound checks.</b>
370 *
371 * @param bytes the UTF-16 encoded bytes
372 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1)
373 * @return the char value
374 */
375 char uncheckedGetUTF16Char(byte[] bytes, int index);
376
377 /**
378 * Put the {@code ch} at {@code index} in a {@code byte[]} in internal
379 * UTF-16 representation.
380 * <p>
381 * <b>WARNING: This method does not perform any bound checks.</b>
382 *
383 * @param bytes the UTF-16 encoded bytes
384 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1)
385 */
386 void uncheckedPutCharUTF16(byte[] bytes, int index, int ch);
387
388 /**
389 * Encode the given string into a sequence of bytes using utf8.
390 *
391 * @param s the string to encode
392 * @return the encoded bytes in utf8
393 * @throws IllegalArgumentException for malformed surrogates
394 */
395 byte[] getBytesUTF8NoRepl(String s);
396
397 /**
398 * Inflated copy from {@code byte[]} to {@code char[]}, as defined by
399 * {@code StringLatin1.inflate}.
400 *
401 * @implSpec Implementations of this method must perform bounds checks.
402 */
403 void inflateBytesToChars(byte[] src, int srcOff, char[] dst, int dstOff, int len);
404
405 /**
406 * Decodes ASCII from the source byte array into the destination
407 * char array.
408 *
409 * @implSpec Implementations of this method must perform bounds checks.
410 *
411 * @return the number of bytes successfully decoded, at most len
412 */
413 int decodeASCII(byte[] src, int srcOff, char[] dst, int dstOff, int len);
414
415 /**
416 * Returns the initial `System.in` to determine if it is replaced
417 * with `System.setIn(newIn)` method
418 */
419 InputStream initialSystemIn();
420
421 /**
422 * Returns the initial value of System.err.
423 */
424 PrintStream initialSystemErr();
425
426 /**
427 * Encodes as many ASCII codepoints as possible from the source
428 * character array into the destination byte array, assuming that
429 * the encoding is ASCII compatible.
430 *
431 * @param sa the source character array
432 * @param sp the index of the source array to start reading from
433 * @param da the target byte array
434 * @param dp the index of the target array to start writing to
435 * @param len the total number of characters to be encoded
436 * @return the total number of characters successfully encoded
437 * @throws NullPointerException if any of the provided arrays is null
438 */
439 int encodeASCII(char[] sa, int sp, byte[] da, int dp, int len);
440
441 /**
442 * Set the cause of Throwable
443 * @param cause set t's cause to new value
444 */
445 void setCause(Throwable t, Throwable cause);
446
447 /**
448 * Get protection domain of the given Class
449 */
450 ProtectionDomain protectionDomain(Class<?> c);
451
452 /**
453 * Get a method handle of string concat helper method
454 */
455 MethodHandle stringConcatHelper(String name, MethodType methodType);
456
457 /**
458 * Get the string concat initial coder
459 */
460 long stringConcatInitialCoder();
461
462 /**
463 * Update lengthCoder for constant
464 */
465 long stringConcatMix(long lengthCoder, String constant);
466
467 /**
468 * Mix value length and coder into current length and coder.
469 */
470 long stringConcatMix(long lengthCoder, char value);
471
472 /**
473 * Creates helper for string concatenation.
474 * <p>
475 * <b>WARNING: The caller of this method shall relinquish and transfer the
476 * ownership of the string array to the callee</b>, since the latter will not
477 * make a copy.
478 */
479 Object uncheckedStringConcat1(String[] constants);
480
481 /**
482 * Get the string initial coder, When COMPACT_STRINGS is on, it returns 0, and when it is off, it returns 1.
483 */
484 byte stringInitCoder();
485
486 /**
487 * Get the Coder of String, which is used by StringConcatFactory to calculate the initCoder of constants
488 */
489 byte stringCoder(String str);
490
491 /**
492 * Join strings
493 */
494 String join(String prefix, String suffix, String delimiter, String[] elements, int size);
495
496 /**
497 * Concatenation of prefix and suffix characters to a String for early bootstrap
498 */
499 String concat(String prefix, Object value, String suffix);
500
501 /*
502 * Get the class data associated with the given class.
503 * @param c the class
504 * @see java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
505 */
506 Object classData(Class<?> c);
507
508 /**
509 * Returns the {@link NativeLibraries} object associated with the provided class loader.
510 * This is used by {@link SymbolLookup#loaderLookup()}.
511 */
512 NativeLibraries nativeLibrariesFor(ClassLoader loader);
513
514 /**
515 * Returns an array of all platform threads.
516 */
517 Thread[] getAllThreads();
518
519 /**
520 * Returns the ThreadContainer for a thread, may be null.
521 */
522 ThreadContainer threadContainer(Thread thread);
523
524 /**
525 * Starts a thread in the given ThreadContainer.
526 */
527 void start(Thread thread, ThreadContainer container);
528
529 /**
530 * Returns the top of the given thread's stackable scope stack.
531 */
532 StackableScope headStackableScope(Thread thread);
533
534 /**
535 * Sets the top of the current thread's stackable scope stack.
536 */
537 void setHeadStackableScope(StackableScope scope);
538
539 /**
540 * Returns the Thread object for the current platform thread. If the
541 * current thread is a virtual thread then this method returns the carrier.
542 */
543 Thread currentCarrierThread();
544
545 /**
546 * Returns the value of the current carrier thread's copy of a thread-local.
547 */
548 <T> T getCarrierThreadLocal(CarrierThreadLocal<T> local);
549
550 /**
551 * Sets the value of the current carrier thread's copy of a thread-local.
552 */
553 <T> void setCarrierThreadLocal(CarrierThreadLocal<T> local, T value);
554
555 /**
556 * Removes the value of the current carrier thread's copy of a thread-local.
557 */
558 void removeCarrierThreadLocal(CarrierThreadLocal<?> local);
559
560 /**
561 * Returns the current thread's scoped values cache
562 */
563 Object[] scopedValueCache();
564
565 /**
566 * Sets the current thread's scoped values cache
567 */
568 void setScopedValueCache(Object[] cache);
569
570 /**
571 * Return the current thread's scoped value bindings.
572 */
573 Object scopedValueBindings();
574
575 /**
576 * Returns the native thread ID for the given platform thread or 0 if not set.
577 */
578 long nativeThreadID(Thread thread);
579
580 /**
581 * Sets the native thread ID for the current platform thread.
582 */
583 void setThreadNativeID(long id);
584
585 /**
586 * Returns the innermost mounted continuation
587 */
588 Continuation getContinuation(Thread thread);
589
590 /**
591 * Sets the innermost mounted continuation
592 */
593 void setContinuation(Thread thread, Continuation continuation);
594
595 /**
596 * The ContinuationScope of virtual thread continuations
597 */
598 ContinuationScope virtualThreadContinuationScope();
599
600 /**
601 * Parks the current virtual thread.
602 * @throws WrongThreadException if the current thread is not a virtual thread
603 */
604 void parkVirtualThread();
605
606 /**
607 * Parks the current virtual thread for up to the given waiting time.
608 * @param nanos the maximum number of nanoseconds to wait
609 * @throws WrongThreadException if the current thread is not a virtual thread
610 */
611 void parkVirtualThread(long nanos);
612
613 /**
614 * Re-enables a virtual thread for scheduling. If the thread was parked then
615 * it will be unblocked, otherwise its next attempt to park will not block
616 * @param thread the virtual thread to unpark
617 * @throws IllegalArgumentException if the thread is not a virtual thread
618 * @throws RejectedExecutionException if the scheduler cannot accept a task
619 */
620 void unparkVirtualThread(Thread thread);
621
622 /**
623 * Returns the default virtual thread scheduler.
624 */
625 Thread.VirtualThreadScheduler defaultVirtualThreadScheduler();
626
627 /**
628 * Returns true if using a custom default virtual thread scheduler.
629 */
630 boolean isCustomDefaultVirtualThreadScheduler();
631
632 /**
633 * Returns the scheduler for the given virtual thread.
634 */
635 Thread.VirtualThreadScheduler virtualThreadScheduler(Thread thread);
636
637 /**
638 * Invokes a supplier to produce a non-null result if this virtual thread is unmounted.
639 * @param supplyIfAlive invoked if this virtual thread is unmounted and alive. The
640 * virtual thread is suspended while the supplier executes
641 * @param supplyIfNotAlive invoked if this virtual thread is not alive
642 * @return the result; {@code null} if mounted, suspended or in transition
643 */
644 <T> T supplyIfUnmounted(Thread thread, Supplier<T> supplyIfAlive, Supplier<T> supplyIfNotAlive);
645
646 /**
647 * Creates a new StackWalker
648 */
649 StackWalker newStackWalkerInstance(Set<StackWalker.Option> options,
650 ContinuationScope contScope,
651 Continuation continuation);
652 /**
653 * Returns '<loader-name>' @<id> if classloader has a name
654 * explicitly set otherwise <qualified-class-name> @<id>
655 */
656 String getLoaderNameID(ClassLoader loader);
657
658 /**
659 * Copy the string bytes to an existing segment, avoiding intermediate copies.
660 */
661 void copyToSegmentRaw(String string, MemorySegment segment, long offset);
662
663 /**
664 * Are the string bytes compatible with the given charset?
665 */
666 boolean bytesCompatible(String string, Charset charset);
667 }