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