1 /*
  2  * Copyright (c) 2003, 2023, 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.lang.annotation.Annotation;
 30 import java.lang.foreign.MemorySegment;
 31 import java.lang.invoke.MethodHandle;
 32 import java.lang.invoke.MethodType;
 33 import java.lang.module.ModuleDescriptor;
 34 import java.lang.reflect.ClassFileFormatVersion;
 35 import java.lang.reflect.Executable;
 36 import java.lang.reflect.Method;
 37 import java.net.URI;
 38 import java.nio.charset.CharacterCodingException;
 39 import java.nio.charset.Charset;
 40 import java.security.AccessControlContext;
 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.Callable;
 46 import java.util.concurrent.ConcurrentHashMap;
 47 import java.util.concurrent.RejectedExecutionException;
 48 import java.util.stream.Stream;
 49 
 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 the constant pool for a class.
 71      */
 72     ConstantPool getConstantPool(Class<?> klass);
 73 
 74     /**
 75      * Compare-And-Set the AnnotationType instance corresponding to this class.
 76      * (This method only applies to annotation types.)
 77      */
 78     boolean casAnnotationType(Class<?> klass, AnnotationType oldType, AnnotationType newType);
 79 
 80     /**
 81      * Get the AnnotationType instance corresponding to this class.
 82      * (This method only applies to annotation types.)
 83      */
 84     AnnotationType getAnnotationType(Class<?> klass);
 85 
 86     /**
 87      * Get the declared annotations for a given class, indexed by their types.
 88      */
 89     Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap(Class<?> klass);
 90 
 91     /**
 92      * Get the array of bytes that is the class-file representation
 93      * of this Class' annotations.
 94      */
 95     byte[] getRawClassAnnotations(Class<?> klass);
 96 
 97     /**
 98      * Get the array of bytes that is the class-file representation
 99      * of this Class' type annotations.
100      */
101     byte[] getRawClassTypeAnnotations(Class<?> klass);
102 
103     /**
104      * Get the array of bytes that is the class-file representation
105      * of this Executable's type annotations.
106      */
107     byte[] getRawExecutableTypeAnnotations(Executable executable);
108 
109     /**
110      * Returns the elements of an enum class or null if the
111      * Class object does not represent an enum type;
112      * the result is uncloned, cached, and shared by all callers.
113      */
114     <E extends Enum<E>> E[] getEnumConstantsShared(Class<E> klass);
115 
116     /**
117      * Set current thread's blocker field.
118      */
119     void blockedOn(Interruptible b);
120 
121     /**
122      * Registers a shutdown hook.
123      *
124      * It is expected that this method with registerShutdownInProgress=true
125      * is only used to register DeleteOnExitHook since the first file
126      * may be added to the delete on exit list by the application shutdown
127      * hooks.
128      *
129      * @param slot  the slot in the shutdown hook array, whose element
130      *              will be invoked in order during shutdown
131      * @param registerShutdownInProgress true to allow the hook
132      *        to be registered even if the shutdown is in progress.
133      * @param hook  the hook to be registered
134      *
135      * @throws IllegalStateException if shutdown is in progress and
136      *         the slot is not valid to register.
137      */
138     void registerShutdownHook(int slot, boolean registerShutdownInProgress, Runnable hook);
139 
140     /**
141      * Returns a new Thread with the given Runnable and an
142      * inherited AccessControlContext.
143      */
144     Thread newThreadWithAcc(Runnable target, @SuppressWarnings("removal") AccessControlContext acc);
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      * Record the non-exported packages of the modules in the given layer
182      */
183     void addNonExportedPackages(ModuleLayer layer);
184 
185     /**
186      * Invalidate package access cache
187      */
188     void invalidatePackageAccessCache();
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 open all packages in the given sets.
245      */
246     void addOpensToAllUnnamed(Module m, Set<String> concealedPkgs, Set<String> exportedPkgs);
247 
248     /**
249      * Updates module m to use a service.
250      */
251     void addUses(Module m, Class<?> service);
252 
253     /**
254      * Returns true if module m reflectively exports a package to other
255      */
256     boolean isReflectivelyExported(Module module, String pn, Module other);
257 
258     /**
259      * Returns true if module m reflectively opens a package to other
260      */
261     boolean isReflectivelyOpened(Module module, String pn, Module other);
262 
263     /**
264      * Updates module m to allow access to restricted methods.
265      */
266     Module addEnableNativeAccess(Module m);
267 
268     /**
269      * Updates all unnamed modules to allow access to restricted methods.
270      */
271     void addEnableNativeAccessToAllUnnamed();
272 
273     /**
274      * Ensure that the given module has native access. If not, warn or
275      * throw exception depending on the configuration.
276      */
277     void ensureNativeAccess(Module m, Class<?> owner, String methodName, Class<?> currentClass);
278 
279     /**
280      * Returns the ServicesCatalog for the given Layer.
281      */
282     ServicesCatalog getServicesCatalog(ModuleLayer layer);
283 
284     /**
285      * Record that this layer has at least one module defined to the given
286      * class loader.
287      */
288     void bindToLoader(ModuleLayer layer, ClassLoader loader);
289 
290     /**
291      * Returns an ordered stream of layers. The first element is the
292      * given layer, the remaining elements are its parents, in DFS order.
293      */
294     Stream<ModuleLayer> layers(ModuleLayer layer);
295 
296     /**
297      * Returns a stream of the layers that have modules defined to the
298      * given class loader.
299      */
300     Stream<ModuleLayer> layers(ClassLoader loader);
301 
302     /**
303      * Count the number of leading positive bytes in the range.
304      */
305     int countPositives(byte[] ba, int off, int len);
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      * Encode the given string into a sequence of bytes using utf8.
359      *
360      * @param s the string to encode
361      * @return the encoded bytes in utf8
362      * @throws IllegalArgumentException for malformed surrogates
363      */
364     byte[] getBytesUTF8NoRepl(String s);
365 
366     /**
367      * Inflated copy from byte[] to char[], as defined by StringLatin1.inflate
368      */
369     void inflateBytesToChars(byte[] src, int srcOff, char[] dst, int dstOff, int len);
370 
371     /**
372      * Decodes ASCII from the source byte array into the destination
373      * char array.
374      *
375      * @return the number of bytes successfully decoded, at most len
376      */
377     int decodeASCII(byte[] src, int srcOff, char[] dst, int dstOff, int len);
378 
379     /**
380      * Returns the initial `System.in` to determine if it is replaced
381      * with `System.setIn(newIn)` method
382      */
383     InputStream initialSystemIn();
384 
385     /**
386      * Encodes ASCII codepoints as possible from the source array into
387      * the destination byte array, assuming that the encoding is ASCII
388      * compatible
389      *
390      * @return the number of bytes successfully encoded, or 0 if none
391      */
392     int encodeASCII(char[] src, int srcOff, byte[] dst, int dstOff, int len);
393 
394     /**
395      * Set the cause of Throwable
396      * @param cause set t's cause to new value
397      */
398     void setCause(Throwable t, Throwable cause);
399 
400     /**
401      * Get protection domain of the given Class
402      */
403     ProtectionDomain protectionDomain(Class<?> c);
404 
405     /**
406      * Get a method handle of string concat helper method
407      */
408     MethodHandle stringConcatHelper(String name, MethodType methodType);
409 
410     /**
411      * Get the string concat initial coder
412      */
413     long stringConcatInitialCoder();
414 
415     /**
416      * Update lengthCoder for constant
417      */
418     long stringConcatMix(long lengthCoder, String constant);
419 
420    /**
421     * Get the coder for the supplied character.
422     */
423    long stringConcatCoder(char value);
424 
425    /**
426     * Update lengthCoder for StringBuilder.
427     */
428    long stringBuilderConcatMix(long lengthCoder, StringBuilder sb);
429 
430     /**
431      * Prepend StringBuilder content.
432     */
433    long stringBuilderConcatPrepend(long lengthCoder, byte[] buf, StringBuilder sb);
434 
435     /**
436      * Join strings
437      */
438     String join(String prefix, String suffix, String delimiter, String[] elements, int size);
439 
440     /*
441      * Get the class data associated with the given class.
442      * @param c the class
443      * @see java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
444      */
445     Object classData(Class<?> c);
446 
447     long findNative(ClassLoader loader, String entry);
448 
449     /**
450      * Direct access to Shutdown.exit to avoid security manager checks
451      * @param statusCode the status code
452      */
453     void exit(int statusCode);
454 
455     /**
456      * Returns an array of all platform threads.
457      */
458     Thread[] getAllThreads();
459 
460     /**
461      * Returns the ThreadContainer for a thread, may be null.
462      */
463     ThreadContainer threadContainer(Thread thread);
464 
465     /**
466      * Starts a thread in the given ThreadContainer.
467      */
468     void start(Thread thread, ThreadContainer container);
469 
470     /**
471      * Returns the top of the given thread's stackable scope stack.
472      */
473     StackableScope headStackableScope(Thread thread);
474 
475     /**
476      * Sets the top of the current thread's stackable scope stack.
477      */
478     void setHeadStackableScope(StackableScope scope);
479 
480     /**
481      * Returns the Thread object for the current platform thread. If the
482      * current thread is a virtual thread then this method returns the carrier.
483      */
484     Thread currentCarrierThread();
485 
486     /**
487      * Executes the given value returning task on the current carrier thread.
488      */
489     <V> V executeOnCarrierThread(Callable<V> task) throws Exception;
490 
491     /**
492      * Returns the value of the current carrier thread's copy of a thread-local.
493      */
494     <T> T getCarrierThreadLocal(CarrierThreadLocal<T> local);
495 
496     /**
497      * Sets the value of the current carrier thread's copy of a thread-local.
498      */
499     <T> void setCarrierThreadLocal(CarrierThreadLocal<T> local, T value);
500 
501     /**
502      * Removes the value of the current carrier thread's copy of a thread-local.
503      */
504     void removeCarrierThreadLocal(CarrierThreadLocal<?> local);
505 
506     /**
507      * Returns {@code true} if there is a value in the current carrier thread's copy of
508      * thread-local, even if that values is {@code null}.
509      */
510     boolean isCarrierThreadLocalPresent(CarrierThreadLocal<?> local);
511 
512     /**
513      * Returns the current thread's scoped values cache
514      */
515     Object[] scopedValueCache();
516 
517     /**
518      * Sets the current thread's scoped values cache
519      */
520     void setScopedValueCache(Object[] cache);
521 
522     /**
523      * Return the current thread's scoped value bindings.
524      */
525     Object scopedValueBindings();
526 
527     /**
528      * Returns the innermost mounted continuation
529      */
530     Continuation getContinuation(Thread thread);
531 
532     /**
533      * Sets the innermost mounted continuation
534      */
535     void setContinuation(Thread thread, Continuation continuation);
536 
537     /**
538      * The ContinuationScope of virtual thread continuations
539      */
540     ContinuationScope virtualThreadContinuationScope();
541 
542     /**
543      * Parks the current virtual thread.
544      * @throws WrongThreadException if the current thread is not a virtual thread
545      */
546     void parkVirtualThread();
547 
548     /**
549      * Parks the current virtual thread for up to the given waiting time.
550      * @param nanos the maximum number of nanoseconds to wait
551      * @throws WrongThreadException if the current thread is not a virtual thread
552      */
553     void parkVirtualThread(long nanos);
554 
555     /**
556      * Re-enables a virtual thread for scheduling. If the thread was parked then
557      * it will be unblocked, otherwise its next attempt to park will not block
558      * @param thread the virtual thread to unpark
559      * @throws IllegalArgumentException if the thread is not a virtual thread
560      * @throws RejectedExecutionException if the scheduler cannot accept a task
561      */
562     void unparkVirtualThread(Thread thread);
563 
564     /**
565      * Creates a new StackWalker
566      */
567     StackWalker newStackWalkerInstance(Set<StackWalker.Option> options,
568                                        ContinuationScope contScope,
569                                        Continuation continuation);
570 
571     /**
572      * Returns the class file format version of the class.
573      */
574     int classFileFormatVersion(Class<?> klass);
575 
576     /**
577      * Returns '<loader-name>' @<id> if classloader has a name
578      * explicitly set otherwise <qualified-class-name> @<id>
579      */
580     String getLoaderNameID(ClassLoader loader);
581 
582     /**
583      * Copy the string bytes to an existing segment, avoiding intermediate copies.
584      */
585     void copyToSegmentRaw(String string, MemorySegment segment, long offset);
586 
587     /**
588      * Are the string bytes compatible with the given charset?
589      */
590     boolean bytesCompatible(String string, Charset charset);
591 }