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.nio.ch.NativeThread;
59 import sun.reflect.annotation.AnnotationType;
60 import sun.nio.ch.Interruptible;
61
62 public interface JavaLangAccess {
63
64 /**
65 * Returns the list of {@code Method} objects for the declared public
66 * methods of this class or interface that have the specified method name
67 * and parameter types.
68 */
69 List<Method> getDeclaredPublicMethods(Class<?> klass, String name, Class<?>... parameterTypes);
70
71 /**
72 * Return most specific method that matches name and parameterTypes.
73 */
74 Method findMethod(Class<?> klass, boolean publicOnly, String name, Class<?>... parameterTypes);
75
76 /**
77 * Return the constant pool for a class.
78 */
79 ConstantPool getConstantPool(Class<?> klass);
80
81 /**
82 * Compare-And-Set the AnnotationType instance corresponding to this class.
83 * (This method only applies to annotation types.)
84 */
85 boolean casAnnotationType(Class<?> klass, AnnotationType oldType, AnnotationType newType);
86
87 /**
88 * Get the AnnotationType instance corresponding to this class.
89 * (This method only applies to annotation types.)
90 */
91 AnnotationType getAnnotationType(Class<?> klass);
92
93 /**
94 * Get the declared annotations for a given class, indexed by their types.
95 */
96 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap(Class<?> klass);
97
98 /**
99 * Get the array of bytes that is the class-file representation
100 * of this Class' annotations.
101 */
102 byte[] getRawClassAnnotations(Class<?> klass);
103
104 /**
105 * Get the array of bytes that is the class-file representation
106 * of this Class' type annotations.
107 */
108 byte[] getRawClassTypeAnnotations(Class<?> klass);
109
110 /**
111 * Get the array of bytes that is the class-file representation
112 * of this Executable's type annotations.
113 */
114 byte[] getRawExecutableTypeAnnotations(Executable executable);
115
116 /**
117 * Get the int value of the Class's class-file access flags.
118 */
119 int getClassFileAccessFlags(Class<?> klass);
120
121 /**
122 * Returns the elements of an enum class or null if the
123 * Class object does not represent an enum type;
124 * the result is uncloned, cached, and shared by all callers.
125 */
126 <E extends Enum<E>> E[] getEnumConstantsShared(Class<E> klass);
127
128 /**
129 * Returns the big-endian packed minor-major version of the class file
130 * of this class.
131 */
132 int classFileVersion(Class<?> clazz);
133
134 /**
135 * Set current thread's blocker field.
136 */
137 void blockedOn(Interruptible b);
138
139 /**
140 * Registers a shutdown hook.
141 *
142 * It is expected that this method with registerShutdownInProgress=true
143 * is only used to register DeleteOnExitHook since the first file
144 * may be added to the delete on exit list by the application shutdown
145 * hooks.
146 *
147 * @param slot the slot in the shutdown hook array, whose element
148 * will be invoked in order during shutdown
149 * @param registerShutdownInProgress true to allow the hook
150 * to be registered even if the shutdown is in progress.
151 * @param hook the hook to be registered
152 *
153 * @throws IllegalStateException if shutdown is in progress and
154 * the slot is not valid to register.
155 */
156 void registerShutdownHook(int slot, boolean registerShutdownInProgress, Runnable hook);
157
158 /**
159 * Invokes the finalize method of the given object.
160 */
161 void invokeFinalize(Object o) throws Throwable;
162
163 /**
164 * Returns the ConcurrentHashMap used as a storage for ClassLoaderValue(s)
165 * associated with the given class loader, creating it if it doesn't already exist.
166 */
167 ConcurrentHashMap<?, ?> createOrGetClassLoaderValueMap(ClassLoader cl);
168
169 /**
170 * Defines a class with the given name to a class loader.
171 */
172 Class<?> defineClass(ClassLoader cl, String name, byte[] b, ProtectionDomain pd, String source);
173
174 /**
175 * Defines a class with the given name to a class loader with
176 * the given flags and class data.
177 *
178 * @see java.lang.invoke.MethodHandles.Lookup#defineClass
179 */
180 Class<?> defineClass(ClassLoader cl, Class<?> lookup, String name, byte[] b, ProtectionDomain pd, boolean initialize, int flags, Object classData);
181
182 /**
183 * Returns a class loaded by the bootstrap class loader.
184 */
185 Class<?> findBootstrapClassOrNull(String name);
186
187 /**
188 * Define a Package of the given name and module by the given class loader.
189 */
190 Package definePackage(ClassLoader cl, String name, Module module);
191
192 /**
193 * Defines a new module to the Java virtual machine. The module
194 * is defined to the given class loader.
195 *
196 * The URI is for information purposes only, it can be {@code null}.
197 */
198 Module defineModule(ClassLoader loader, ModuleDescriptor descriptor, URI uri);
199
200 /**
201 * Defines the unnamed module for the given class loader.
202 */
203 Module defineUnnamedModule(ClassLoader loader);
204
205 /**
206 * Updates the readability so that module m1 reads m2. The new read edge
207 * does not result in a strong reference to m2 (m2 can be GC'ed).
208 *
209 * This method is the same as m1.addReads(m2) but without a permission check.
210 */
211 void addReads(Module m1, Module m2);
212
213 /**
214 * Updates module m to read all unnamed modules.
215 */
216 void addReadsAllUnnamed(Module m);
217
218 /**
219 * Updates module m1 to export a package unconditionally.
220 */
221 void addExports(Module m1, String pkg);
222
223 /**
224 * Updates module m1 to export a package to module m2. The export does
225 * not result in a strong reference to m2 (m2 can be GC'ed).
226 */
227 void addExports(Module m1, String pkg, Module m2);
228
229 /**
230 * Updates a module m to export a package to all unnamed modules.
231 */
232 void addExportsToAllUnnamed(Module m, String pkg);
233
234 /**
235 * Updates module m1 to open a package to module m2. Opening the
236 * package does not result in a strong reference to m2 (m2 can be GC'ed).
237 */
238 void addOpens(Module m1, String pkg, Module m2);
239
240 /**
241 * Updates module m to open a package to all unnamed modules.
242 */
243 void addOpensToAllUnnamed(Module m, String pkg);
244
245 /**
246 * Updates module m to use a service.
247 */
248 void addUses(Module m, Class<?> service);
249
250 /**
251 * Returns true if module m reflectively exports a package to other
252 */
253 boolean isReflectivelyExported(Module module, String pn, Module other);
254
255 /**
256 * Returns true if module m reflectively opens a package to other
257 */
258 boolean isReflectivelyOpened(Module module, String pn, Module other);
259
260 /**
261 * Updates module m to allow access to restricted methods.
262 */
263 Module addEnableNativeAccess(Module m);
264
265 /**
266 * Updates module named {@code name} in layer {@code layer} to allow access to restricted methods.
267 * Returns true iff the given module exists in the given layer.
268 */
269 boolean addEnableNativeAccess(ModuleLayer layer, String name);
270
271 /**
272 * Updates all unnamed modules to allow access to restricted methods.
273 */
274 void addEnableNativeAccessToAllUnnamed();
275
276 /**
277 * Ensure that the given module has native access. If not, warn or throw exception depending on the configuration.
278 * @param m the module in which native access occurred
279 * @param owner the owner of the restricted method being called (or the JNI method being bound)
280 * @param methodName the name of the restricted method being called (or the JNI method being bound)
281 * @param currentClass the class calling the restricted method (for JNI, this is the same as {@code owner})
282 * @param jni {@code true}, if this event is related to a JNI method being bound
283 */
284 void ensureNativeAccess(Module m, Class<?> owner, String methodName, Class<?> currentClass, boolean jni);
285
286 /**
287 * Returns the ServicesCatalog for the given Layer.
288 */
289 ServicesCatalog getServicesCatalog(ModuleLayer layer);
290
291 /**
292 * Record that this layer has at least one module defined to the given
293 * class loader.
294 */
295 void bindToLoader(ModuleLayer layer, ClassLoader loader);
296
297 /**
298 * Returns an ordered stream of layers. The first element is the
299 * given layer, the remaining elements are its parents, in DFS order.
300 */
301 Stream<ModuleLayer> layers(ModuleLayer layer);
302
303 /**
304 * Returns a stream of the layers that have modules defined to the
305 * given class loader.
306 */
307 Stream<ModuleLayer> layers(ClassLoader loader);
308
309 /**
310 * Count the number of leading positive bytes in the range.
311 *
312 * @implSpec Implementations of this method must perform bounds checks.
313 */
314 int countPositives(byte[] ba, int off, int len);
315
316 /**
317 * Count the number of leading non-zero ascii chars in the String.
318 */
319 int countNonZeroAscii(String s);
320
321 /**
322 * Constructs a new {@code String} by decoding the specified byte array
323 * using the specified {@linkplain java.nio.charset.Charset charset}.
324 * <p>
325 * <b>WARNING: The caller of this method shall relinquish and transfer the
326 * ownership of the byte array to the callee</b>, since the latter will not
327 * make a copy.
328 *
329 * @param bytes the byte array source
330 * @param cs the Charset
331 * @return the newly created string
332 * @throws CharacterCodingException for malformed or unmappable bytes
333 */
334 String uncheckedNewStringNoRepl(byte[] bytes, Charset cs) throws CharacterCodingException;
335
336 /**
337 * Encode the given string into a sequence of bytes using the specified
338 * {@linkplain java.nio.charset.Charset charset}.
339 * <p>
340 * <b>WARNING: This method returns the {@code byte[]} backing the provided
341 * {@code String}, if the input is ASCII. Hence, the returned byte array
342 * must not be modified.</b>
343 * <p>
344 * This method throws {@code CharacterCodingException} instead of replacing
345 * when malformed input or unmappable characters are encountered.
346 *
347 * @param s the string to encode
348 * @param cs the charset
349 * @return the encoded bytes
350 * @throws CharacterCodingException for malformed input or unmappable characters
351 */
352 byte[] uncheckedGetBytesNoRepl(String s, Charset cs) throws CharacterCodingException;
353
354 /**
355 * Returns a new string by decoding from the given UTF-8 bytes array.
356 *
357 * @param off the index of the first byte to decode
358 * @param len the number of bytes to decode
359 * @return the newly created string
360 * @throws IllegalArgumentException for malformed or unmappable bytes.
361 */
362 String newStringUTF8NoRepl(byte[] bytes, int off, int len);
363
364 /**
365 * Get the {@code char} at {@code index} in a {@code byte[]} in internal
366 * UTF-16 representation.
367 * <p>
368 * <b>WARNING: This method does not perform any bound checks.</b>
369 *
370 * @param bytes the UTF-16 encoded bytes
371 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1)
372 * @return the char value
373 */
374 char uncheckedGetUTF16Char(byte[] bytes, int index);
375
376 /**
377 * Put the {@code ch} at {@code index} in a {@code byte[]} in internal
378 * UTF-16 representation.
379 * <p>
380 * <b>WARNING: This method does not perform any bound checks.</b>
381 *
382 * @param bytes the UTF-16 encoded bytes
383 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1)
384 */
385 void uncheckedPutCharUTF16(byte[] bytes, int index, int ch);
386
387 /**
388 * Encode the given string into a sequence of bytes using utf8.
389 *
390 * @param s the string to encode
391 * @return the encoded bytes in utf8
392 * @throws IllegalArgumentException for malformed surrogates
393 */
394 byte[] getBytesUTF8NoRepl(String s);
395
396 /**
397 * Inflated copy from {@code byte[]} to {@code char[]}, as defined by
398 * {@code StringLatin1.inflate}.
399 *
400 * @implSpec Implementations of this method must perform bounds checks.
401 */
402 void inflateBytesToChars(byte[] src, int srcOff, char[] dst, int dstOff, int len);
403
404 /**
405 * Decodes ASCII from the source byte array into the destination
406 * char array.
407 *
408 * @implSpec Implementations of this method must perform bounds checks.
409 *
410 * @return the number of bytes successfully decoded, at most len
411 */
412 int decodeASCII(byte[] src, int srcOff, char[] dst, int dstOff, int len);
413
414 /**
415 * Returns the initial `System.in` to determine if it is replaced
416 * with `System.setIn(newIn)` method
417 */
418 InputStream initialSystemIn();
419
420 /**
421 * Returns the initial value of System.err.
422 */
423 PrintStream initialSystemErr();
424
425 /**
426 * Encodes as many ASCII codepoints as possible from the source array into
427 * the destination byte array, assuming that the encoding is ASCII
428 * compatible.
429 * <p>
430 * <b>WARNING: This method does not perform any bound checks.</b>
431 *
432 * @return the number of bytes successfully encoded, or 0 if none
433 */
434 int uncheckedEncodeASCII(char[] src, int srcOff, byte[] dst, int dstOff, int len);
435
436 /**
437 * Set the cause of Throwable
438 * @param cause set t's cause to new value
439 */
440 void setCause(Throwable t, Throwable cause);
441
442 /**
443 * Get protection domain of the given Class
444 */
445 ProtectionDomain protectionDomain(Class<?> c);
446
447 /**
448 * Get a method handle of string concat helper method
449 */
450 MethodHandle stringConcatHelper(String name, MethodType methodType);
451
452 /**
453 * Get the string concat initial coder
454 */
455 long stringConcatInitialCoder();
456
457 /**
458 * Update lengthCoder for constant
459 */
460 long stringConcatMix(long lengthCoder, String constant);
461
462 /**
463 * Mix value length and coder into current length and coder.
464 */
465 long stringConcatMix(long lengthCoder, char value);
466
467 /**
468 * Creates helper for string concatenation.
469 * <p>
470 * <b>WARNING: The caller of this method shall relinquish and transfer the
471 * ownership of the string array to the callee</b>, since the latter will not
472 * make a copy.
473 */
474 Object uncheckedStringConcat1(String[] constants);
475
476 /**
477 * Get the string initial coder, When COMPACT_STRINGS is on, it returns 0, and when it is off, it returns 1.
478 */
479 byte stringInitCoder();
480
481 /**
482 * Get the Coder of String, which is used by StringConcatFactory to calculate the initCoder of constants
483 */
484 byte stringCoder(String str);
485
486 /**
487 * Join strings
488 */
489 String join(String prefix, String suffix, String delimiter, String[] elements, int size);
490
491 /**
492 * Concatenation of prefix and suffix characters to a String for early bootstrap
493 */
494 String concat(String prefix, Object value, String suffix);
495
496 /*
497 * Get the class data associated with the given class.
498 * @param c the class
499 * @see java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
500 */
501 Object classData(Class<?> c);
502
503 /**
504 * Returns the {@link NativeLibraries} object associated with the provided class loader.
505 * This is used by {@link SymbolLookup#loaderLookup()}.
506 */
507 NativeLibraries nativeLibrariesFor(ClassLoader loader);
508
509 /**
510 * Returns an array of all platform threads.
511 */
512 Thread[] getAllThreads();
513
514 /**
515 * Returns the ThreadContainer for a thread, may be null.
516 */
517 ThreadContainer threadContainer(Thread thread);
518
519 /**
520 * Starts a thread in the given ThreadContainer.
521 */
522 void start(Thread thread, ThreadContainer container);
523
524 /**
525 * Returns the top of the given thread's stackable scope stack.
526 */
527 StackableScope headStackableScope(Thread thread);
528
529 /**
530 * Sets the top of the current thread's stackable scope stack.
531 */
532 void setHeadStackableScope(StackableScope scope);
533
534 /**
535 * Returns the Thread object for the current platform thread. If the
536 * current thread is a virtual thread then this method returns the carrier.
537 */
538 Thread currentCarrierThread();
539
540 /**
541 * Returns the value of the current carrier thread's copy of a thread-local.
542 */
543 <T> T getCarrierThreadLocal(CarrierThreadLocal<T> local);
544
545 /**
546 * Sets the value of the current carrier thread's copy of a thread-local.
547 */
548 <T> void setCarrierThreadLocal(CarrierThreadLocal<T> local, T value);
549
550 /**
551 * Removes the value of the current carrier thread's copy of a thread-local.
552 */
553 void removeCarrierThreadLocal(CarrierThreadLocal<?> local);
554
555 /**
556 * Returns the current thread's scoped values cache
557 */
558 Object[] scopedValueCache();
559
560 /**
561 * Sets the current thread's scoped values cache
562 */
563 void setScopedValueCache(Object[] cache);
564
565 /**
566 * Return the current thread's scoped value bindings.
567 */
568 Object scopedValueBindings();
569
570 /**
571 * Returns the NativeThread for signalling, null if not set.
572 */
573 NativeThread nativeThread(Thread thread);
574
575 /**
576 * Sets the NativeThread for the current platform thread.
577 */
578 void setNativeThread(NativeThread nt);
579
580 /**
581 * Returns the innermost mounted continuation
582 */
583 Continuation getContinuation(Thread thread);
584
585 /**
586 * Sets the innermost mounted continuation
587 */
588 void setContinuation(Thread thread, Continuation continuation);
589
590 /**
591 * The ContinuationScope of virtual thread continuations
592 */
593 ContinuationScope virtualThreadContinuationScope();
594
595 /**
596 * Parks the current virtual thread.
597 * @throws WrongThreadException if the current thread is not a virtual thread
598 */
599 void parkVirtualThread();
600
601 /**
602 * Parks the current virtual thread for up to the given waiting time.
603 * @param nanos the maximum number of nanoseconds to wait
604 * @throws WrongThreadException if the current thread is not a virtual thread
605 */
606 void parkVirtualThread(long nanos);
607
608 /**
609 * Re-enables a virtual thread for scheduling. If the thread was parked then
610 * it will be unblocked, otherwise its next attempt to park will not block
611 * @param thread the virtual thread to unpark
612 * @throws IllegalArgumentException if the thread is not a virtual thread
613 * @throws RejectedExecutionException if the scheduler cannot accept a task
614 */
615 void unparkVirtualThread(Thread thread);
616
617 /**
618 * Returns the default virtual thread scheduler.
619 */
620 Thread.VirtualThreadScheduler defaultVirtualThreadScheduler();
621
622 /**
623 * Returns true if using a custom default virtual thread scheduler.
624 */
625 boolean isCustomDefaultVirtualThreadScheduler();
626
627 /**
628 * Returns the scheduler for the given virtual thread.
629 */
630 Thread.VirtualThreadScheduler virtualThreadScheduler(Thread thread);
631
632 /**
633 * Invokes a supplier to produce a non-null result if this virtual thread is unmounted.
634 * @param supplyIfAlive invoked if this virtual thread is unmounted and alive. The
635 * virtual thread is suspended while the supplier executes
636 * @param supplyIfNotAlive invoked if this virtual thread is not alive
637 * @return the result; {@code null} if mounted, suspended or in transition
638 */
639 <T> T supplyIfUnmounted(Thread thread, Supplier<T> supplyIfAlive, Supplier<T> supplyIfNotAlive);
640
641 /**
642 * Creates a new StackWalker
643 */
644 StackWalker newStackWalkerInstance(Set<StackWalker.Option> options,
645 ContinuationScope contScope,
646 Continuation continuation);
647 /**
648 * Returns '<loader-name>' @<id> if classloader has a name
649 * explicitly set otherwise <qualified-class-name> @<id>
650 */
651 String getLoaderNameID(ClassLoader loader);
652
653 /**
654 * Copy the string bytes to an existing segment, avoiding intermediate copies.
655 */
656 void copyToSegmentRaw(String string, MemorySegment segment, long offset);
657
658 /**
659 * Are the string bytes compatible with the given charset?
660 */
661 boolean bytesCompatible(String string, Charset charset);
662 }