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.stream.Stream;
48
49 import jdk.internal.loader.NativeLibraries;
50 import jdk.internal.misc.CarrierThreadLocal;
51 import jdk.internal.module.ServicesCatalog;
52 import jdk.internal.reflect.ConstantPool;
53 import jdk.internal.vm.Continuation;
54 import jdk.internal.vm.ContinuationScope;
55 import jdk.internal.vm.StackableScope;
56 import jdk.internal.vm.ThreadContainer;
57 import sun.reflect.annotation.AnnotationType;
58 import sun.nio.ch.Interruptible;
59
60 public interface JavaLangAccess {
61
62 /**
63 * Returns the list of {@code Method} objects for the declared public
64 * methods of this class or interface that have the specified method name
65 * and parameter types.
66 */
67 List<Method> getDeclaredPublicMethods(Class<?> klass, String name, Class<?>... parameterTypes);
68
69 /**
70 * Return most specific method that matches name and parameterTypes.
71 */
72 Method findMethod(Class<?> klass, boolean publicOnly, String name, Class<?>... parameterTypes);
73
74 /**
75 * Return the constant pool for a class.
76 */
77 ConstantPool getConstantPool(Class<?> klass);
78
79 /**
80 * Compare-And-Set the AnnotationType instance corresponding to this class.
81 * (This method only applies to annotation types.)
82 */
83 boolean casAnnotationType(Class<?> klass, AnnotationType oldType, AnnotationType newType);
84
85 /**
86 * Get the AnnotationType instance corresponding to this class.
87 * (This method only applies to annotation types.)
88 */
89 AnnotationType getAnnotationType(Class<?> klass);
90
91 /**
92 * Get the declared annotations for a given class, indexed by their types.
93 */
94 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap(Class<?> klass);
95
96 /**
97 * Get the array of bytes that is the class-file representation
98 * of this Class' annotations.
99 */
100 byte[] getRawClassAnnotations(Class<?> klass);
101
102 /**
103 * Get the array of bytes that is the class-file representation
104 * of this Class' type annotations.
105 */
106 byte[] getRawClassTypeAnnotations(Class<?> klass);
107
108 /**
109 * Get the array of bytes that is the class-file representation
110 * of this Executable's type annotations.
111 */
112 byte[] getRawExecutableTypeAnnotations(Executable executable);
113
114 /**
115 * Get the int value of the Class's class-file access flags.
116 */
117 int getClassFileAccessFlags(Class<?> klass);
118
119 /**
120 * Returns the elements of an enum class or null if the
121 * Class object does not represent an enum type;
122 * the result is uncloned, cached, and shared by all callers.
123 */
124 <E extends Enum<E>> E[] getEnumConstantsShared(Class<E> klass);
125
126 /**
127 * Returns the big-endian packed minor-major version of the class file
128 * of this class.
129 */
130 int classFileVersion(Class<?> clazz);
131
132 /**
133 * Set current thread's blocker field.
134 */
135 void blockedOn(Interruptible b);
136
137 /**
138 * Registers a shutdown hook.
139 *
140 * It is expected that this method with registerShutdownInProgress=true
141 * is only used to register DeleteOnExitHook since the first file
142 * may be added to the delete on exit list by the application shutdown
143 * hooks.
144 *
145 * @param slot the slot in the shutdown hook array, whose element
146 * will be invoked in order during shutdown
147 * @param registerShutdownInProgress true to allow the hook
148 * to be registered even if the shutdown is in progress.
149 * @param hook the hook to be registered
150 *
151 * @throws IllegalStateException if shutdown is in progress and
152 * the slot is not valid to register.
153 */
154 void registerShutdownHook(int slot, boolean registerShutdownInProgress, Runnable hook);
155
156 /**
157 * Invokes the finalize method of the given object.
158 */
159 void invokeFinalize(Object o) throws Throwable;
160
161 /**
162 * Returns the ConcurrentHashMap used as a storage for ClassLoaderValue(s)
163 * associated with the given class loader, creating it if it doesn't already exist.
164 */
165 ConcurrentHashMap<?, ?> createOrGetClassLoaderValueMap(ClassLoader cl);
166
167 /**
168 * Defines a class with the given name to a class loader.
169 */
170 Class<?> defineClass(ClassLoader cl, String name, byte[] b, ProtectionDomain pd, String source);
171
172 /**
173 * Defines a class with the given name to a class loader with
174 * the given flags and class data.
175 *
176 * @see java.lang.invoke.MethodHandles.Lookup#defineClass
177 */
178 Class<?> defineClass(ClassLoader cl, Class<?> lookup, String name, byte[] b, ProtectionDomain pd, boolean initialize, int flags, Object classData);
179
180 /**
181 * Returns a class loaded by the bootstrap class loader.
182 */
183 Class<?> findBootstrapClassOrNull(String name);
184
185 /**
186 * Define a Package of the given name and module by the given class loader.
187 */
188 Package definePackage(ClassLoader cl, String name, Module module);
189
190 /**
191 * Defines a new module to the Java virtual machine. The module
192 * is defined to the given class loader.
193 *
194 * The URI is for information purposes only, it can be {@code null}.
195 */
196 Module defineModule(ClassLoader loader, ModuleDescriptor descriptor, URI uri);
197
198 /**
199 * Defines the unnamed module for the given class loader.
200 */
201 Module defineUnnamedModule(ClassLoader loader);
202
203 /**
204 * Updates the readability so that module m1 reads m2. The new read edge
205 * does not result in a strong reference to m2 (m2 can be GC'ed).
206 *
207 * This method is the same as m1.addReads(m2) but without a permission check.
208 */
209 void addReads(Module m1, Module m2);
210
211 /**
212 * Updates module m to read all unnamed modules.
213 */
214 void addReadsAllUnnamed(Module m);
215
216 /**
217 * Updates module m1 to export a package unconditionally.
218 */
219 void addExports(Module m1, String pkg);
220
221 /**
222 * Updates module m1 to export a package to module m2. The export does
223 * not result in a strong reference to m2 (m2 can be GC'ed).
224 */
225 void addExports(Module m1, String pkg, Module m2);
226
227 /**
228 * Updates a module m to export a package to all unnamed modules.
229 */
230 void addExportsToAllUnnamed(Module m, String pkg);
231
232 /**
233 * Updates module m1 to open a package to module m2. Opening the
234 * package does not result in a strong reference to m2 (m2 can be GC'ed).
235 */
236 void addOpens(Module m1, String pkg, Module m2);
237
238 /**
239 * Updates module m to open a package to all unnamed modules.
240 */
241 void addOpensToAllUnnamed(Module m, String pkg);
242
243 /**
244 * Updates module m to use a service.
245 */
246 void addUses(Module m, Class<?> service);
247
248 /**
249 * Returns true if module m reflectively exports a package to other
250 */
251 boolean isReflectivelyExported(Module module, String pn, Module other);
252
253 /**
254 * Returns true if module m reflectively opens a package to other
255 */
256 boolean isReflectivelyOpened(Module module, String pn, Module other);
257
258 /**
259 * Updates module m to allow access to restricted methods.
260 */
261 Module addEnableNativeAccess(Module m);
262
263 /**
264 * Updates module named {@code name} in layer {@code layer} to allow access to restricted methods.
265 * Returns true iff the given module exists in the given layer.
266 */
267 boolean addEnableNativeAccess(ModuleLayer layer, String name);
268
269 /**
270 * Updates all unnamed modules to allow access to restricted methods.
271 */
272 void addEnableNativeAccessToAllUnnamed();
273
274 /**
275 * Ensure that the given module has native access. If not, warn or throw exception depending on the configuration.
276 * @param m the module in which native access occurred
277 * @param owner the owner of the restricted method being called (or the JNI method being bound)
278 * @param methodName the name of the restricted method being called (or the JNI method being bound)
279 * @param currentClass the class calling the restricted method (for JNI, this is the same as {@code owner})
280 * @param jni {@code true}, if this event is related to a JNI method being bound
281 */
282 void ensureNativeAccess(Module m, Class<?> owner, String methodName, Class<?> currentClass, boolean jni);
283
284 /**
285 * Returns the ServicesCatalog for the given Layer.
286 */
287 ServicesCatalog getServicesCatalog(ModuleLayer layer);
288
289 /**
290 * Record that this layer has at least one module defined to the given
291 * class loader.
292 */
293 void bindToLoader(ModuleLayer layer, ClassLoader loader);
294
295 /**
296 * Returns an ordered stream of layers. The first element is the
297 * given layer, the remaining elements are its parents, in DFS order.
298 */
299 Stream<ModuleLayer> layers(ModuleLayer layer);
300
301 /**
302 * Returns a stream of the layers that have modules defined to the
303 * given class loader.
304 */
305 Stream<ModuleLayer> layers(ClassLoader loader);
306
307 /**
308 * Count the number of leading positive bytes in the range.
309 *
310 * @implSpec Implementations of this method must perform bounds checks.
311 */
312 int countPositives(byte[] ba, int off, int len);
313
314 /**
315 * Count the number of leading non-zero ascii chars in the String.
316 */
317 int countNonZeroAscii(String s);
318
319 /**
320 * Constructs a new {@code String} with the supplied Latin1 bytes.
321 * <p>
322 * <b>WARNING: The caller of this method shall relinquish and transfer the
323 * ownership of the byte array to the callee</b>, since the latter will not
324 * make a copy.
325 *
326 * @param bytes the byte array source
327 * @return the newly created string
328 */
329 String uncheckedNewStringWithLatin1Bytes(byte[] bytes);
330
331 /**
332 * Constructs a new {@code String} by decoding the specified byte array
333 * using the specified {@code Charset}.
334 * <p>
335 * <b>WARNING: The caller of this method shall relinquish and transfer the
336 * ownership of the byte array to the callee</b>, since the latter will not
337 * make a copy.
338 *
339 * @param bytes the byte array source
340 * @param cs the Charset
341 * @return the newly created string
342 * @throws CharacterCodingException for malformed or unmappable bytes
343 * @throws NullPointerException If {@code bytes} or {@code cs} is null
344 */
345 String uncheckedNewStringOrThrow(byte[] bytes, Charset cs) throws CharacterCodingException;
346
347 /**
348 * {@return the sequence of bytes obtained by encoding the given string in
349 * the specified {@code 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 *
355 * @param s the string to encode
356 * @param cs the charset
357 * @throws NullPointerException If {@code s} or {@code cs} is null
358 * @throws CharacterCodingException for malformed input or unmappable characters
359 */
360 byte[] uncheckedGetBytesOrThrow(String s, Charset cs) throws CharacterCodingException;
361
362 /**
363 * Get the {@code char} at {@code index} in a {@code byte[]} in internal
364 * UTF-16 representation.
365 * <p>
366 * <b>WARNING: This method does not perform any bound checks.</b>
367 *
368 * @param bytes the UTF-16 encoded bytes
369 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1)
370 * @return the char value
371 */
372 char uncheckedGetUTF16Char(byte[] bytes, int index);
373
374 /**
375 * Put the {@code ch} at {@code index} in a {@code byte[]} in internal
376 * UTF-16 representation.
377 * <p>
378 * <b>WARNING: This method does not perform any bound checks.</b>
379 *
380 * @param bytes the UTF-16 encoded bytes
381 * @param index of the char to retrieve, 0 <= index < (bytes.length >> 1)
382 */
383 void uncheckedPutCharUTF16(byte[] bytes, int index, int ch);
384
385 /**
386 * {@return the sequence of bytes obtained by encoding the given string in UTF-8}
387 *
388 * @param s the string to encode
389 * @throws NullPointerException If {@code s} is null
390 * @throws CharacterCodingException For malformed input or unmappable characters
391 */
392 byte[] getBytesUTF8OrThrow(String s) throws CharacterCodingException;
393
394 /**
395 * Inflated copy from {@code byte[]} to {@code char[]}, as defined by
396 * {@code StringLatin1.inflate}.
397 *
398 * @implSpec Implementations of this method must perform bounds checks.
399 */
400 void inflateBytesToChars(byte[] src, int srcOff, char[] dst, int dstOff, int len);
401
402 /**
403 * Decodes ASCII from the source byte array into the destination
404 * char array.
405 *
406 * @implSpec Implementations of this method must perform bounds checks.
407 *
408 * @return the number of bytes successfully decoded, at most len
409 */
410 int decodeASCII(byte[] src, int srcOff, char[] dst, int dstOff, int len);
411
412 /**
413 * Returns the initial `System.in` to determine if it is replaced
414 * with `System.setIn(newIn)` method
415 */
416 InputStream initialSystemIn();
417
418 /**
419 * Returns the initial value of System.err.
420 */
421 PrintStream initialSystemErr();
422
423 /**
424 * Encodes as many ASCII codepoints as possible from the source
425 * character array into the destination byte array, assuming that
426 * the encoding is ASCII compatible.
427 *
428 * @param sa the source character array
429 * @param sp the index of the source array to start reading from
430 * @param da the target byte array
431 * @param dp the index of the target array to start writing to
432 * @param len the total number of characters to be encoded
433 * @return the total number of characters successfully encoded
434 * @throws NullPointerException if any of the provided arrays is null
435 */
436 int encodeASCII(char[] sa, int sp, byte[] da, int dp, int len);
437
438 /**
439 * Set the cause of Throwable
440 * @param cause set t's cause to new value
441 */
442 void setCause(Throwable t, Throwable cause);
443
444 /**
445 * Get protection domain of the given Class
446 */
447 ProtectionDomain protectionDomain(Class<?> c);
448
449 /**
450 * Get a method handle of string concat helper method
451 */
452 MethodHandle stringConcatHelper(String name, MethodType methodType);
453
454 /**
455 * Get the string concat initial coder
456 */
457 long stringConcatInitialCoder();
458
459 /**
460 * Update lengthCoder for constant
461 */
462 long stringConcatMix(long lengthCoder, String constant);
463
464 /**
465 * Mix value length and coder into current length and coder.
466 */
467 long stringConcatMix(long lengthCoder, char value);
468
469 /**
470 * Creates helper for string concatenation.
471 * <p>
472 * <b>WARNING: The caller of this method shall relinquish and transfer the
473 * ownership of the string array to the callee</b>, since the latter will not
474 * make a copy.
475 */
476 Object uncheckedStringConcat1(String[] constants);
477
478 /**
479 * Get the string initial coder, When COMPACT_STRINGS is on, it returns 0, and when it is off, it returns 1.
480 */
481 byte stringInitCoder();
482
483 /**
484 * Get the Coder of String, which is used by StringConcatFactory to calculate the initCoder of constants
485 */
486 byte stringCoder(String str);
487
488 /**
489 * Join strings
490 */
491 String join(String prefix, String suffix, String delimiter, String[] elements, int size);
492
493 /**
494 * Concatenation of prefix and suffix characters to a String for early bootstrap
495 */
496 String concat(String prefix, Object value, String suffix);
497
498 /*
499 * Get the class data associated with the given class.
500 * @param c the class
501 * @see java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
502 */
503 Object classData(Class<?> c);
504
505 /**
506 * Returns the {@link NativeLibraries} object associated with the provided class loader.
507 * This is used by {@link SymbolLookup#loaderLookup()}.
508 */
509 NativeLibraries nativeLibrariesFor(ClassLoader loader);
510
511 /**
512 * Returns an array of all platform threads.
513 */
514 Thread[] getAllThreads();
515
516 /**
517 * Returns the ThreadContainer for a thread, may be null.
518 */
519 ThreadContainer threadContainer(Thread thread);
520
521 /**
522 * Starts a thread in the given ThreadContainer.
523 */
524 void start(Thread thread, ThreadContainer container);
525
526 /**
527 * Returns the top of the given thread's stackable scope stack.
528 */
529 StackableScope headStackableScope(Thread thread);
530
531 /**
532 * Sets the top of the current thread's stackable scope stack.
533 */
534 void setHeadStackableScope(StackableScope scope);
535
536 /**
537 * Returns the Thread object for the current platform thread. If the
538 * current thread is a virtual thread then this method returns the carrier.
539 */
540 Thread currentCarrierThread();
541
542 /**
543 * Returns the value of the current carrier thread's copy of a thread-local.
544 */
545 <T> T getCarrierThreadLocal(CarrierThreadLocal<T> local);
546
547 /**
548 * Sets the value of the current carrier thread's copy of a thread-local.
549 */
550 <T> void setCarrierThreadLocal(CarrierThreadLocal<T> local, T value);
551
552 /**
553 * Removes the value of the current carrier thread's copy of a thread-local.
554 */
555 void removeCarrierThreadLocal(CarrierThreadLocal<?> local);
556
557 /**
558 * Returns the current thread's scoped values cache
559 */
560 Object[] scopedValueCache();
561
562 /**
563 * Sets the current thread's scoped values cache
564 */
565 void setScopedValueCache(Object[] cache);
566
567 /**
568 * Return the current thread's scoped value bindings.
569 */
570 Object scopedValueBindings();
571
572 /**
573 * Returns the native thread ID for the given platform thread or 0 if not set.
574 */
575 long nativeThreadID(Thread thread);
576
577 /**
578 * Sets the native thread ID for the current platform thread.
579 */
580 void setThreadNativeID(long id);
581
582 /**
583 * Returns the innermost mounted continuation
584 */
585 Continuation getContinuation(Thread thread);
586
587 /**
588 * Sets the innermost mounted continuation
589 */
590 void setContinuation(Thread thread, Continuation continuation);
591
592 /**
593 * The ContinuationScope of virtual thread continuations
594 */
595 ContinuationScope virtualThreadContinuationScope();
596
597 /**
598 * Parks the current virtual thread.
599 * @throws WrongThreadException if the current thread is not a virtual thread
600 */
601 void parkVirtualThread();
602
603 /**
604 * Parks the current virtual thread for up to the given waiting time.
605 * @param nanos the maximum number of nanoseconds to wait
606 * @throws WrongThreadException if the current thread is not a virtual thread
607 */
608 void parkVirtualThread(long nanos);
609
610 /**
611 * Re-enables a virtual thread for scheduling. If the thread was parked then
612 * it will be unblocked, otherwise its next attempt to park will not block
613 * @param thread the virtual thread to unpark
614 * @throws IllegalArgumentException if the thread is not a virtual thread
615 * @throws RejectedExecutionException if the scheduler cannot accept a task
616 */
617 void unparkVirtualThread(Thread thread);
618
619 /**
620 * Returns the default virtual thread scheduler.
621 */
622 Thread.VirtualThreadScheduler defaultVirtualThreadScheduler();
623
624 /**
625 * Returns true if using a custom default virtual thread scheduler.
626 */
627 boolean isCustomDefaultVirtualThreadScheduler();
628
629 /**
630 * Returns the scheduler for the given virtual thread.
631 */
632 Thread.VirtualThreadScheduler virtualThreadScheduler(Thread thread);
633
634 /**
635 * Creates a new StackWalker
636 */
637 StackWalker newStackWalkerInstance(Set<StackWalker.Option> options,
638 ContinuationScope contScope,
639 Continuation continuation);
640 /**
641 * Returns '<loader-name>' @<id> if classloader has a name
642 * explicitly set otherwise <qualified-class-name> @<id>
643 */
644 String getLoaderNameID(ClassLoader loader);
645
646 /**
647 * Copy the string bytes to an existing segment, avoiding intermediate copies.
648 */
649 void copyToSegmentRaw(String string, MemorySegment segment, long offset);
650
651 /**
652 * Are the string bytes compatible with the given charset?
653 */
654 boolean bytesCompatible(String string, Charset charset);
655 }