/* * Copyright (c) 1997, 2022, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. *
*/
/* NOTE about use of any ctor or function call that can trigger a safepoint/GC: such ctors and calls MUST NOT come between an oop declaration/init and its usage because if objects are move this may cause various memory stomps, bus errors and segfaults. Here is a cookbook for causing so called "naked oop failures":
JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredFields<etc> { // Object address to be held directly in mirror & not visible to GC oop mirror = JNIHandles::resolve_non_null(ofClass);
// If this ctor can hit a safepoint, moving objects around, then ComplexConstructor foo;
// Boom! mirror may point to JUNK instead of the intended object (some dereference of mirror)
// Here's another call that may block for GC, making mirror stale MutexLocker ml(some_lock);
// And here's an initializer that can result in a stale oop // all in one step. oop o = call_that_can_throw_exception(TRAPS);
The solution is to keep the oop declaration BELOW the ctor or function call that might cause a GC, do another resolve to reassign the oop, or consider use of a Handle instead of an oop so there is immunity from object motion. But note that the "QUICK" entries below do not have a handlemark and thus can only support use of handles passed in.
*/
while (!vfst.at_end()) {
Method* m = vfst.method(); if (!vfst.method()->method_holder()->is_subclass_of(vmClasses::ClassLoader_klass())&&
!vfst.method()->method_holder()->is_subclass_of(access_controller_klass) &&
!vfst.method()->method_holder()->is_subclass_of(privileged_action_klass)) { break;
}
last_caller = m;
vfst.next();
} // if this is called from Class.forName0 and that is called from Class.forName, // then print the caller of Class.forName. If this is Class.loadClass, then print // that caller, otherwise keep quiet since this should be picked up elsewhere. bool found_it = false; if (!vfst.at_end() &&
vfst.method()->method_holder()->name() == vmSymbols::java_lang_Class() &&
vfst.method()->name() == vmSymbols::forName0_name()) {
vfst.next(); if (!vfst.at_end() &&
vfst.method()->method_holder()->name() == vmSymbols::java_lang_Class() &&
vfst.method()->name() == vmSymbols::forName_name()) {
vfst.next();
found_it = true;
}
} elseif (last_caller != NULL &&
last_caller->method_holder()->name() ==
vmSymbols::java_lang_ClassLoader() &&
last_caller->name() == vmSymbols::loadClass_name()) {
found_it = true;
} elseif (!vfst.at_end()) { if (vfst.method()->is_native()) { // JNI call
found_it = true;
}
} if (found_it && !vfst.at_end()) { // found the caller
caller = vfst.method()->method_holder();
line_number = vfst.method()->line_number_from_bci(vfst.bci()); if (line_number == -1) { // show method name if it's a native method
trace = vfst.method()->name_and_sig_as_C_string();
}
Symbol* s = caller->source_file_name(); if (s != NULL) {
source_file = s->as_C_string();
}
}
} if (caller != NULL) { if (to_class != caller) { constchar * from = caller->external_name(); constchar * to = to_class->external_name(); // print in a single call to reduce interleaving between threads if (source_file != NULL) {
log_debug(class, resolve)("%s %s %s:%d (%s)", from, to, source_file, line_number, trace);
} else {
log_debug(class, resolve)("%s %s (%s)", from, to, trace);
}
}
}
}
// The function below is actually exposed by jdk.internal.misc.VM and not // java.lang.System, but we choose to keep it here so that it stays next // to JVM_CurrentTimeMillis and JVM_NanoTime
// We're going to verify that the result can fit in a long. // For that we need the difference in seconds between 'seconds' // and 'offset_secs' to be such that: // |seconds - offset_secs| < (2^63/10^9) // We're going to approximate 10^9 ~< 2^30 (1000^3 ~< 1024^3) // which makes |seconds - offset_secs| < 2^33 // and we will prefer +/- 2^32 as the maximum acceptable diff // as 2^32 has a more natural feel than 2^33... // // So if |seconds - offset_secs| >= 2^32 - we return a special // sentinel value (-1) which the caller should take as an // exception value indicating that the offset given to us is // too far from range of the current time - leading to too big // a nano adjustment. The caller is expected to recover by // computing a more accurate offset and calling this method // again. (For the record 2^32 secs is ~136 years, so that // should rarely happen) //
jlong diff = seconds - offset_secs; if (diff >= MAX_DIFF_SECS || diff <= MIN_DIFF_SECS) { return -1; // sentinel value: the offset is too far off the target
}
// return the adjustment. If you compute a time by adding // this number of nanoseconds along with the number of seconds // in the offset you should get the current UTC time. return (diff * (jlong)1000000000) + nanos;
JVM_END
JVM_ENTRY(void, JVM_ArrayCopy(JNIEnv *env, jclass ignored, jobject src, jint src_pos,
jobject dst, jint dst_pos, jint length)) // Check if we have null pointers if (src == NULL || dst == NULL) { THROW(vmSymbols::java_lang_NullPointerException());
}
arrayOop s = arrayOop(JNIHandles::resolve_non_null(src));
arrayOop d = arrayOop(JNIHandles::resolve_non_null(dst));
assert(oopDesc::is_oop(s), "JVM_ArrayCopy: src not an oop");
assert(oopDesc::is_oop(d), "JVM_ArrayCopy: dst not an oop"); // Do copy
s->klass()->copy_array(s, src_pos, d, dst_pos, length, thread);
JVM_END
/* * Return all of the system properties in a Java String array with alternating * names and values from the jvm SystemProperty. * Which includes some internal and all commandline -D defined properties.
*/
JVM_ENTRY(jobjectArray, JVM_GetProperties(JNIEnv *env))
ResourceMark rm(THREAD);
HandleMark hm(THREAD); int ndx = 0; int fixedCount = 2;
SystemProperty* p = Arguments::system_properties(); int count = Arguments::PropertyList_count(p);
// Allocate result String array
InstanceKlass* ik = vmClasses::String_klass();
objArrayOop r = oopFactory::new_objArray(ik, (count + fixedCount) * 2, CHECK_NULL);
objArrayHandle result_h(THREAD, r);
// Convert the -XX:MaxDirectMemorySize= command line flag // to the sun.nio.MaxDirectMemorySize property. // Do this after setting user properties to prevent people // from setting the value with a -D option, as requested. // Leave empty if not supplied if (!FLAG_IS_DEFAULT(MaxDirectMemorySize)) { char as_chars[256];
jio_snprintf(as_chars, sizeof(as_chars), JULONG_FORMAT, MaxDirectMemorySize);
Handle key_str = java_lang_String::create_from_platform_dependent_str("sun.nio.MaxDirectMemorySize", CHECK_NULL);
Handle value_str = java_lang_String::create_from_platform_dependent_str(as_chars, CHECK_NULL);
result_h->obj_at_put(ndx * 2, key_str());
result_h->obj_at_put(ndx * 2 + 1, value_str());
ndx++;
}
// JVM monitoring and management support // Add the sun.management.compiler property for the compiler's name
{ #undef CSIZE #ifdefined(_LP64) || defined(_WIN64) #define CSIZE "64-Bit " #else #define CSIZE #endif// 64bit
/* * Return the temporary directory that the VM uses for the attach * and perf data files. * * It is important that this directory is well-known and the * same for all VM instances. It cannot be affected by configuration * variables such as java.io.tmpdir.
*/
JVM_ENTRY(jstring, JVM_GetTemporaryDirectory(JNIEnv *env))
HandleMark hm(THREAD); constchar* temp_dir = os::get_temp_directory();
Handle h = java_lang_String::create_from_platform_dependent_str(temp_dir, CHECK_NULL); return (jstring) JNIHandles::make_local(THREAD, h());
JVM_END
JVM_ENTRY_NO_ENV(void, JVM_BeforeHalt()) #if INCLUDE_CDS // Link all classes for dynamic CDS dumping before vm exit. if (DynamicArchive::should_dump_at_vm_exit()) {
DynamicArchive::prepare_for_dump_at_exit();
} #endif
EventShutdown event; if (event.should_commit()) {
event.set_reason("Shutdown requested from Java");
event.commit();
}
JVM_END
staticinline jlong convert_size_t_to_jlong(size_t val) { // In the 64-bit vm, a size_t can overflow a jlong (which is signed).
NOT_LP64 (return (jlong)val;)
LP64_ONLY(return (jlong)MIN2(val, (size_t)max_jlong);)
}
JVM_ENTRY_NO_ENV(jlong, JVM_TotalMemory(void))
size_t n = Universe::heap()->capacity(); return convert_size_t_to_jlong(n);
JVM_END
JVM_ENTRY_NO_ENV(jlong, JVM_FreeMemory(void))
size_t n = Universe::heap()->unused(); return convert_size_t_to_jlong(n);
JVM_END
JVM_ENTRY_NO_ENV(jlong, JVM_MaxMemory(void))
size_t n = Universe::heap()->max_capacity(); return convert_size_t_to_jlong(n);
JVM_END
Handle stackStream_h(THREAD, JNIHandles::resolve_non_null(stackStream));
Handle contScope_h(THREAD, JNIHandles::resolve(contScope));
Handle cont_h(THREAD, JNIHandles::resolve(cont)); // frames array is a Class<?>[] array when only getting caller reference, // and a StackFrameInfo[] array (or derivative) otherwise. It should never // be null.
objArrayOop fa = objArrayOop(JNIHandles::resolve_non_null(frames));
objArrayHandle frames_array_h(THREAD, fa);
int limit = start_index + frame_count; if (frames_array_h->length() < limit) {
THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(), "not enough space in buffers", NULL);
}
JVM_ENTRY(jint, JVM_MoreStackWalk(JNIEnv *env, jobject stackStream, jlong mode, jlong anchor,
jint frame_count, jint start_index,
jobjectArray frames)) // frames array is a Class<?>[] array when only getting caller reference, // and a StackFrameInfo[] array (or derivative) otherwise. It should never // be null.
objArrayOop fa = objArrayOop(JNIHandles::resolve_non_null(frames));
objArrayHandle frames_array_h(THREAD, fa);
int limit = start_index+frame_count; if (frames_array_h->length() < limit) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "not enough space in buffers");
}
// The current thread already owns the monitor and it has not yet // been added to the wait queue so the current thread cannot be // made the successor. This means that the JVMTI_EVENT_MONITOR_WAIT // event handler cannot accidentally consume an unpark() meant for // the ParkEvent associated with this ObjectMonitor.
}
ObjectSynchronizer::wait(obj, ms, CHECK);
JVM_END
#ifdef ASSERT // Just checking that the cloneable flag is set correct if (obj->is_array()) {
guarantee(klass->is_cloneable(), "all arrays are cloneable");
} else {
guarantee(obj->is_instance(), "should be instanceOop"); bool cloneable = klass->is_subtype_of(vmClasses::Cloneable_klass());
guarantee(cloneable == klass->is_cloneable(), "incorrect cloneable flag");
} #endif
// Check if class of obj supports the Cloneable interface. // All arrays are considered to be cloneable (See JLS 20.1.5). // All j.l.r.Reference classes are considered non-cloneable. if (!klass->is_cloneable() ||
(klass->is_instance_klass() &&
InstanceKlass::cast(klass)->reference_type() != REF_NONE)) {
ResourceMark rm(THREAD);
THROW_MSG_0(vmSymbols::java_lang_CloneNotSupportedException(), klass->external_name());
}
Handle new_obj(THREAD, new_obj_oop); // Caution: this involves a java upcall, so the clone should be // "gc-robust" by this stage. if (klass->has_finalizer()) {
assert(obj->is_instance(), "should be instanceOop");
new_obj_oop = InstanceKlass::register_finalizer(instanceOop(new_obj()), CHECK_NULL);
new_obj = Handle(THREAD, new_obj_oop);
}
// Misc. class handling ///////////////////////////////////////////////////////////
JVM_ENTRY(jclass, JVM_GetCallerClass(JNIEnv* env)) // Getting the class of the caller frame. // // The call stack at this point looks something like this: // // [0] [ @CallerSensitive public sun.reflect.Reflection.getCallerClass ] // [1] [ @CallerSensitive API.method ] // [.] [ (skipped intermediate frames) ] // [n] [ caller ]
vframeStream vfst(thread); // Cf. LibraryCallKit::inline_native_Reflection_getCallerClass for (int n = 0; !vfst.at_end(); vfst.security_next(), n++) {
Method* m = vfst.method();
assert(m != NULL, "sanity"); switch (n) { case 0: // This must only be called from Reflection.getCallerClass if (m->intrinsic_id() != vmIntrinsics::_getCallerClass) {
THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "JVM_GetCallerClass must only be called from Reflection.getCallerClass");
} // fall-through case 1: // Frame 0 and 1 must be caller sensitive. if (!m->caller_sensitive()) {
THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), err_msg("CallerSensitive annotation expected at frame %d", n));
} break; default: if (!m->is_ignored_by_security_stack_walk()) { // We have reached the desired frame; return the holder class. return (jclass) JNIHandles::make_local(THREAD, m->method_holder()->java_mirror());
} break;
}
} return NULL;
JVM_END
// Returns a class loaded by the bootstrap class loader; or null // if not found. ClassNotFoundException is not thrown. // FindClassFromBootLoader is exported to the launcher for windows.
JVM_ENTRY(jclass, JVM_FindClassFromBootLoader(JNIEnv* env, constchar* name)) // Java libraries should ensure that name is never null or illegal. if (name == NULL || (int)strlen(name) > Symbol::max_length()) { // It's impossible to create this class; the name cannot fit // into the constant pool. return NULL;
}
assert(UTF8::is_legal_utf8((constunsignedchar*)name, (int)strlen(name), false), "illegal UTF name");
TempNewSymbol h_name = SymbolTable::new_symbol(name);
Klass* k = SystemDictionary::resolve_or_null(h_name, CHECK_NULL); if (k == NULL) { return NULL;
}
// Find a class with this name in this loader, using the caller's protection domain.
JVM_ENTRY(jclass, JVM_FindClassFromCaller(JNIEnv* env, constchar* name,
jboolean init, jobject loader,
jclass caller))
TempNewSymbol h_name =
SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_ClassNotFoundException(),
CHECK_NULL);
oop loader_oop = JNIHandles::resolve(loader);
oop from_class = JNIHandles::resolve(caller);
oop protection_domain = NULL; // If loader is null, shouldn't call ClassLoader.checkPackageAccess; otherwise get // NPE. Put it in another way, the bootstrap class loader has all permission and // thus no checkPackageAccess equivalence in the VM class loader. // The caller is also passed as NULL by the java code if there is no security // manager to avoid the performance cost of getting the calling class. if (from_class != NULL && loader_oop != NULL) {
protection_domain = java_lang_Class::as_Klass(from_class)->protection_domain();
}
if (log_is_enabled(Debug, class, resolve) && result != NULL) {
trace_class_resolution(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(result)));
} return result;
JVM_END
// Currently only called from the old verifier.
JVM_ENTRY(jclass, JVM_FindClassFromClass(JNIEnv *env, constchar *name,
jboolean init, jclass from))
TempNewSymbol h_name =
SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_ClassNotFoundException(),
CHECK_NULL);
oop from_class_oop = JNIHandles::resolve(from);
Klass* from_class = (from_class_oop == NULL)
? (Klass*)NULL
: java_lang_Class::as_Klass(from_class_oop);
oop class_loader = NULL;
oop protection_domain = NULL; if (from_class != NULL) {
class_loader = from_class->class_loader();
protection_domain = from_class->protection_domain();
}
Handle h_loader(THREAD, class_loader);
Handle h_prot (THREAD, protection_domain);
jclass result = find_class_from_class_loader(env, h_name, init, h_loader,
h_prot, true, thread);
if (log_is_enabled(Debug, class, resolve) && result != NULL) { // this function is generally only used for class loading during verification.
ResourceMark rm;
oop from_mirror = JNIHandles::resolve_non_null(from);
Klass* from_class = java_lang_Class::as_Klass(from_mirror); constchar * from_name = from_class->external_name();
if (UsePerfData) {
ClassLoader::perf_app_classfile_bytes_read()->inc(len);
}
// Class resolution will get the class name from the .class stream if the name is null.
TempNewSymbol class_name = name == NULL ? NULL :
SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_NoClassDefFoundError(),
CHECK_NULL);
/* * Define a class with the specified flags that indicates if it's a nestmate, * hidden, or strongly referenced from class loader.
*/ static jclass jvm_lookup_define_class(jclass lookup, constchar *name, const jbyte *buf, jsize len, jobject pd,
jboolean init, int flags, jobject classData, TRAPS) {
ResourceMark rm(THREAD);
Klass* lookup_k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(lookup)); // Lookup class must be a non-null instance if (lookup_k == NULL) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Lookup class is null");
}
assert(lookup_k->is_instance_klass(), "Lookup class must be an instance klass");
if (!is_hidden) { // classData is only applicable for hidden classes if (classData != NULL) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "classData is only applicable for hidden classes");
} if (is_nestmate) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "dynamic nestmate is only applicable for hidden classes");
} if (!is_strong) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "an ordinary class must be strongly referenced by its defining loader");
} if (vm_annotations) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "vm annotations only allowed for hidden classes");
} if (flags != STRONG_LOADER_LINK) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(),
err_msg("invalid flag 0x%x", flags));
}
}
// Class resolution will get the class name from the .class stream if the name is null.
TempNewSymbol class_name = name == NULL ? NULL :
SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_NoClassDefFoundError(),
CHECK_NULL);
// The hidden class loader data has been artificially been kept alive to // this point. The mirror and any instances of this class have to keep // it alive afterwards.
ik->class_loader_data()->dec_keep_alive();
if (is_nestmate && log_is_enabled(Debug, class, nestmates)) {
ModuleEntry* module = ik->module(); constchar * module_name = module->is_named() ? module->name()->as_C_string() : UNNAMED_MODULE;
log_debug(class, nestmates)("Dynamic nestmate: %s/%s, nest_host %s, %s",
module_name,
ik->external_name(),
host_class->external_name(),
ik->is_hidden() ? "is hidden" : "is not hidden");
}
}
assert(Reflection::is_same_class_package(lookup_k, ik), "lookup class and defined class are in different packages");
if (init) {
ik->initialize(CHECK_NULL);
} else {
ik->link_class(CHECK_NULL);
}
/* * Define a class with the specified lookup class. * lookup: Lookup class * name: the name of the class * buf: class bytes * len: length of class bytes * pd: protection domain * init: initialize the class * flags: properties of the class * classData: private static pre-initialized field
*/
JVM_ENTRY(jclass, JVM_LookupDefineClass(JNIEnv *env, jclass lookup, constchar *name, const jbyte *buf,
jsize len, jobject pd, jboolean initialize, int flags, jobject classData))
if (lookup == NULL) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Lookup class is null");
}
// Internalize the string, converting '.' to '/' in string. char* p = (char*)str; while (*p != '\0') { if (*p == '.') {
*p = '/';
}
p++;
}
constint str_len = (int)(p - str); if (str_len > Symbol::max_length()) { // It's impossible to create this class; the name cannot fit // into the constant pool. return NULL;
}
TempNewSymbol klass_name = SymbolTable::new_symbol(str, str_len);
// Security Note: // The Java level wrapper will perform the necessary security check allowing // us to pass the NULL as the initiating class loader.
Handle h_loader(THREAD, JNIHandles::resolve(loader));
Klass* k = SystemDictionary::find_instance_or_array_klass(THREAD, klass_name,
h_loader,
Handle()); #if INCLUDE_CDS if (k == NULL) { // If the class is not already loaded, try to see if it's in the shared // archive for the current classloader (h_loader).
k = SystemDictionaryShared::find_or_load_shared_class(klass_name, h_loader, CHECK_NULL);
} #endif return (k == NULL) ? NULL :
(jclass) JNIHandles::make_local(THREAD, k->java_mirror());
JVM_END
// Module support //////////////////////////////////////////////////////////////////////////////
// Special handling for primitive objects if (java_lang_Class::is_primitive(mirror)) { // Primitive objects does not have any interfaces
objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL); return (jobjectArray) JNIHandles::make_local(THREAD, r);
}
Klass* klass = java_lang_Class::as_Klass(mirror); // Figure size of result array int size; if (klass->is_instance_klass()) {
size = InstanceKlass::cast(klass)->local_interfaces()->length();
} else {
assert(klass->is_objArray_klass() || klass->is_typeArray_klass(), "Illegal mirror klass");
size = 2;
}
// Allocate result array
objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(), size, CHECK_NULL);
objArrayHandle result (THREAD, r); // Fill in result if (klass->is_instance_klass()) { // Regular instance klass, fill in all local interfaces for (int index = 0; index < size; index++) {
Klass* k = InstanceKlass::cast(klass)->local_interfaces()->at(index);
result->obj_at_put(index, k->java_mirror());
}
} else { // All arrays implement java.lang.Cloneable and java.io.Serializable
result->obj_at_put(0, vmClasses::Cloneable_klass()->java_mirror());
result->obj_at_put(1, vmClasses::Serializable_klass()->java_mirror());
} return (jobjectArray) JNIHandles::make_local(THREAD, result());
JVM_END
JVM_ENTRY(jboolean, JVM_IsInterface(JNIEnv *env, jclass cls))
oop mirror = JNIHandles::resolve_non_null(cls); if (java_lang_Class::is_primitive(mirror)) { return JNI_FALSE;
}
Klass* k = java_lang_Class::as_Klass(mirror);
jboolean result = k->is_interface();
assert(!result || k->is_instance_klass(), "all interfaces are instance types"); // The compiler intrinsic for isInterface tests the // Klass::_access_flags bits in the same way. return result;
JVM_END
JVM_ENTRY(jobjectArray, JVM_GetClassSigners(JNIEnv *env, jclass cls))
JvmtiVMObjectAllocEventCollector oam;
oop mirror = JNIHandles::resolve_non_null(cls); if (java_lang_Class::is_primitive(mirror)) { // There are no signers for primitive types return NULL;
}
// If there are no signers set in the class, or if the class // is an array, return NULL. if (signers == NULL) return NULL;
// copy of the signers array
Klass* element = ObjArrayKlass::cast(signers->klass())->element_klass();
objArrayOop signers_copy = oopFactory::new_objArray(element, signers->length(), CHECK_NULL); for (int index = 0; index < signers->length(); index++) {
signers_copy->obj_at_put(index, signers->obj_at(index));
}
// return the copy return (jobjectArray) JNIHandles::make_local(THREAD, signers_copy);
JVM_END
JVM_ENTRY(void, JVM_SetClassSigners(JNIEnv *env, jclass cls, jobjectArray signers))
oop mirror = JNIHandles::resolve_non_null(cls); if (!java_lang_Class::is_primitive(mirror)) { // This call is ignored for primitive types and arrays. // Signers are only set once, ClassLoader.java, and thus shouldn't // be called with an array. Only the bootstrap loader creates arrays.
Klass* k = java_lang_Class::as_Klass(mirror); if (k->is_instance_klass()) {
java_lang_Class::set_signers(k->java_mirror(), objArrayOop(JNIHandles::resolve(signers)));
}
}
JVM_END
// Returns the inherited_access_control_context field of the running thread.
JVM_ENTRY(jobject, JVM_GetInheritedAccessControlContext(JNIEnv *env, jclass cls))
oop result = java_lang_Thread::inherited_access_control_context(thread->threadObj()); return JNIHandles::make_local(THREAD, result);
JVM_END
JVM_ENTRY(jobject, JVM_GetStackAccessControlContext(JNIEnv *env, jclass cls)) if (!UsePrivilegedStack) return NULL;
ResourceMark rm(THREAD);
GrowableArray<Handle>* local_array = new GrowableArray<Handle>(12);
JvmtiVMObjectAllocEventCollector oam;
// count the protection domains on the execution stack. We collapse // duplicate consecutive protection domains into a single one, as // well as stopping when we hit a privileged frame.
// Iterate through Java frames
vframeStream vfst(thread); for(; !vfst.at_end(); vfst.next()) { // get method of frame
Method* method = vfst.method();
// stop at the first privileged frame if (method->method_holder() == vmClasses::AccessController_klass() &&
method->name() == vmSymbols::executePrivileged_name())
{ // this frame is privileged
is_privileged = true;
// either all the domains on the stack were system domains, or // we had a privileged system domain if (local_array->is_empty()) { if (is_privileged && privileged_context.is_null()) return NULL;
// Iterate through Java frames
vframeStream vfst(thread); for(; !vfst.at_end(); vfst.next()) { int loc = -1; // get method of frame
Method* method = vfst.method();
Symbol *name = method->name();
InstanceKlass* holder = method->method_holder(); if (name == vmSymbols::runWith_method_name()) { if ((holder == resolver.Carrier_klass
|| holder == vmClasses::VirtualThread_klass()
|| holder == vmClasses::Thread_klass())) {
loc = 1;
}
}
Klass* k = java_lang_Class::as_Klass(mirror);
debug_only(int computed_modifiers = k->compute_modifier_flags());
assert(k->modifier_flags() == computed_modifiers, "modifiers cache is OK"); return k->modifier_flags();
JVM_END
// Inner class reflection ///////////////////////////////////////////////////////////////////////////////
JVM_ENTRY(jobjectArray, JVM_GetDeclaredClasses(JNIEnv *env, jclass ofClass))
JvmtiVMObjectAllocEventCollector oam; // ofClass is a reference to a java_lang_Class object. The mirror object // of an InstanceKlass
oop ofMirror = JNIHandles::resolve_non_null(ofClass); if (java_lang_Class::is_primitive(ofMirror) ||
! java_lang_Class::as_Klass(ofMirror)->is_instance_klass()) {
oop result = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL); return (jobjectArray)JNIHandles::make_local(THREAD, result);
}
InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
InnerClassesIterator iter(k);
if (iter.length() == 0) { // Neither an inner nor outer class
oop result = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL); return (jobjectArray)JNIHandles::make_local(THREAD, result);
}
// find inner class info
constantPoolHandle cp(thread, k->constants()); int length = iter.length();
// Allocate temp. result array
objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(), length/4, CHECK_NULL);
objArrayHandle result (THREAD, r); int members = 0;
for (; !iter.done(); iter.next()) { int ioff = iter.inner_class_info_index(); int ooff = iter.outer_class_info_index();
if (ioff != 0 && ooff != 0) { // Check to see if the name matches the class we're looking for // before attempting to find the class. if (cp->klass_name_at_matches(k, ooff)) {
Klass* outer_klass = cp->klass_at(ooff, CHECK_NULL); if (outer_klass == k) {
Klass* ik = cp->klass_at(ioff, CHECK_NULL);
InstanceKlass* inner_klass = InstanceKlass::cast(ik);
// Throws an exception if outer klass has not declared k as // an inner klass
Reflection::check_for_inner_class(k, inner_klass, true, CHECK_NULL);
JVM_ENTRY(jclass, JVM_GetDeclaringClass(JNIEnv *env, jclass ofClass))
{ // ofClass is a reference to a java_lang_Class object.
oop ofMirror = JNIHandles::resolve_non_null(ofClass); if (java_lang_Class::is_primitive(ofMirror)) { return NULL;
}
Klass* klass = java_lang_Class::as_Klass(ofMirror); if (!klass->is_instance_klass()) { return NULL;
}
bool inner_is_member = false;
Klass* outer_klass
= InstanceKlass::cast(klass)->compute_enclosing_class(&inner_is_member, CHECK_NULL); if (outer_klass == NULL) return NULL; // already a top-level class if (!inner_is_member) return NULL; // a hidden class (inside a method) return (jclass) JNIHandles::make_local(THREAD, outer_klass->java_mirror());
}
JVM_END
JVM_ENTRY(jstring, JVM_GetSimpleBinaryName(JNIEnv *env, jclass cls))
{
oop mirror = JNIHandles::resolve_non_null(cls); if (java_lang_Class::is_primitive(mirror)) { return NULL;
}
Klass* klass = java_lang_Class::as_Klass(mirror); if (!klass->is_instance_klass()) { return NULL;
}
InstanceKlass* k = InstanceKlass::cast(klass); int ooff = 0, noff = 0; if (k->find_inner_classes_attr(&ooff, &noff, THREAD)) { if (noff != 0) {
constantPoolHandle i_cp(thread, k->constants());
Symbol* name = i_cp->symbol_at(noff);
Handle str = java_lang_String::create_from_symbol(name, CHECK_NULL); return (jstring) JNIHandles::make_local(THREAD, str());
}
} return NULL;
}
JVM_END
JVM_ENTRY(jstring, JVM_GetClassSignature(JNIEnv *env, jclass cls))
assert (cls != NULL, "illegal class");
JvmtiVMObjectAllocEventCollector oam;
ResourceMark rm(THREAD);
oop mirror = JNIHandles::resolve_non_null(cls); // Return null for arrays and primitives if (!java_lang_Class::is_primitive(mirror)) {
Klass* k = java_lang_Class::as_Klass(mirror); if (k->is_instance_klass()) {
Symbol* sym = InstanceKlass::cast(k)->generic_signature(); if (sym == NULL) return NULL;
Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL); return (jstring) JNIHandles::make_local(THREAD, str());
}
} return NULL;
JVM_END
JVM_ENTRY(jbyteArray, JVM_GetClassAnnotations(JNIEnv *env, jclass cls))
assert (cls != NULL, "illegal class");
oop mirror = JNIHandles::resolve_non_null(cls); // Return null for arrays and primitives if (!java_lang_Class::is_primitive(mirror)) {
Klass* k = java_lang_Class::as_Klass(mirror); if (k->is_instance_klass()) {
typeArrayOop a = Annotations::make_java_array(InstanceKlass::cast(k)->class_annotations(), CHECK_NULL); return (jbyteArray) JNIHandles::make_local(THREAD, a);
}
} return NULL;
JVM_END
staticbool jvm_get_field_common(jobject field, fieldDescriptor& fd) { // some of this code was adapted from from jni_FromReflectedField
oop reflected = JNIHandles::resolve_non_null(field);
oop mirror = java_lang_reflect_Field::clazz(reflected);
Klass* k = java_lang_Class::as_Klass(mirror); int slot = java_lang_reflect_Field::slot(reflected); int modifiers = java_lang_reflect_Field::modifiers(reflected);
InstanceKlass* ik = InstanceKlass::cast(k);
intptr_t offset = ik->field_offset(slot);
if (modifiers & JVM_ACC_STATIC) { // for static fields we only look in the current class if (!ik->find_local_field_from_offset(offset, true, &fd)) {
assert(false, "cannot find static field"); returnfalse;
}
} else { // for instance fields we start with the current class and work // our way up through the superclass chain if (!ik->find_field_from_offset(offset, false, &fd)) {
assert(false, "cannot find instance field"); returnfalse;
}
} returntrue;
}
static Method* jvm_get_method_common(jobject method) { // some of this code was adapted from from jni_FromReflectedMethod
Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);
assert(m != NULL, "cannot find method"); return m; // caller has to deal with NULL in product mode
}
/* Type use annotations support (JDK 1.8) */
JVM_ENTRY(jbyteArray, JVM_GetClassTypeAnnotations(JNIEnv *env, jclass cls))
assert (cls != NULL, "illegal class");
ResourceMark rm(THREAD); // Return null for arrays and primitives if (!java_lang_Class::is_primitive(JNIHandles::resolve(cls))) {
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve(cls)); if (k->is_instance_klass()) {
AnnotationArray* type_annotations = InstanceKlass::cast(k)->class_type_annotations(); if (type_annotations != NULL) {
typeArrayOop a = Annotations::make_java_array(type_annotations, CHECK_NULL); return (jbyteArray) JNIHandles::make_local(THREAD, a);
}
}
} return NULL;
JVM_END
JVM_ENTRY(jbyteArray, JVM_GetMethodTypeAnnotations(JNIEnv *env, jobject method))
assert (method != NULL, "illegal method"); // method is a handle to a java.lang.reflect.Method object
Method* m = jvm_get_method_common(method); if (m == NULL) { return NULL;
}
AnnotationArray* type_annotations = m->type_annotations(); if (type_annotations != NULL) {
typeArrayOop a = Annotations::make_java_array(type_annotations, CHECK_NULL); return (jbyteArray) JNIHandles::make_local(THREAD, a);
}
staticvoid bounds_check(const constantPoolHandle& cp, jint index, TRAPS) { if (!cp->is_within_bounds(index)) {
THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "Constant pool index out of bounds");
}
}
JVM_ENTRY(jobjectArray, JVM_GetMethodParameters(JNIEnv *env, jobject method))
{ // method is a handle to a java.lang.reflect.Method object
Method* method_ptr = jvm_get_method_common(method);
methodHandle mh (THREAD, method_ptr);
Handle reflected_method (THREAD, JNIHandles::resolve_non_null(method)); constint num_params = mh->method_parameters_length();
if (num_params < 0) { // A -1 return value from method_parameters_length means there is no // parameter data. Return null to indicate this to the reflection // API.
assert(num_params == -1, "num_params should be -1 if it is less than zero"); return (jobjectArray)NULL;
} else { // Otherwise, we return something up to reflection, even if it is // a zero-length array. Why? Because in some cases this can // trigger a MalformedParametersException.
// make sure all the symbols are properly formatted for (int i = 0; i < num_params; i++) {
MethodParametersElement* params = mh->method_parameters_start(); int index = params[i].name_cp_index;
constantPoolHandle cp(THREAD, mh->constants());
bounds_check(cp, index, CHECK_NULL);
if (0 != index && !mh->constants()->tag_at(index).is_utf8()) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
}
}
objArrayOop result_oop = oopFactory::new_objArray(vmClasses::reflect_Parameter_klass(), num_params, CHECK_NULL);
objArrayHandle result (THREAD, result_oop);
for (int i = 0; i < num_params; i++) {
MethodParametersElement* params = mh->method_parameters_start(); // For a 0 index, give a NULL symbol
Symbol* sym = 0 != params[i].name_cp_index ?
mh->constants()->symbol_at(params[i].name_cp_index) : NULL; int flags = params[i].flags;
oop param = Reflection::new_parameter(reflected_method, i, sym,
flags, CHECK_NULL);
result->obj_at_put(i, param);
} return (jobjectArray)JNIHandles::make_local(THREAD, result());
}
}
JVM_END
// New (JDK 1.4) reflection implementation /////////////////////////////////////
InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
constantPoolHandle cp(THREAD, k->constants());
// Ensure class is linked
k->link_class(CHECK_NULL);
// Allocate result int num_fields;
if (publicOnly) {
num_fields = 0; for (JavaFieldStream fs(k); !fs.done(); fs.next()) { if (fs.access_flags().is_public()) ++num_fields;
}
} else {
num_fields = k->java_fields_count();
}
objArrayOop r = oopFactory::new_objArray(vmClasses::reflect_Field_klass(), num_fields, CHECK_NULL);
objArrayHandle result (THREAD, r);
int out_idx = 0;
fieldDescriptor fd; for (JavaFieldStream fs(k); !fs.done(); fs.next()) { if (!publicOnly || fs.access_flags().is_public()) {
fd.reinitialize(k, fs.index());
oop field = Reflection::new_field(&fd, CHECK_NULL);
result->obj_at_put(out_idx, field);
++out_idx;
}
}
assert(out_idx == num_fields, "just checking"); return (jobjectArray) JNIHandles::make_local(THREAD, result());
}
JVM_END
// A class is a record if and only if it is final and a direct subclass of // java.lang.Record and has a Record attribute; otherwise, it is not a record.
JVM_ENTRY(jboolean, JVM_IsRecord(JNIEnv *env, jclass cls))
{
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls)); if (k != NULL && k->is_instance_klass()) {
InstanceKlass* ik = InstanceKlass::cast(k); return ik->is_record();
} else { returnfalse;
}
}
JVM_END
// Returns an array containing the components of the Record attribute, // or NULL if the attribute is not present. // // Note that this function returns the components of the Record attribute // even if the class is not a record.
JVM_ENTRY(jobjectArray, JVM_GetRecordComponents(JNIEnv* env, jclass ofClass))
{
Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(ofClass));
assert(c->is_instance_klass(), "must be");
InstanceKlass* ik = InstanceKlass::cast(c);
InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
// Ensure class is linked
k->link_class(CHECK_NULL);
Array<Method*>* methods = k->methods(); int methods_length = methods->length();
// Save original method_idnum in case of redefinition, which can change // the idnum of obsolete methods. The new method will have the same idnum // but if we refresh the methods array, the counts will be wrong.
ResourceMark rm(THREAD);
GrowableArray<int>* idnums = new GrowableArray<int>(methods_length); int num_methods = 0;
for (int i = 0; i < methods_length; i++) {
methodHandle method(THREAD, methods->at(i)); if (select_method(method, want_constructor)) { if (!publicOnly || method->is_public()) {
idnums->push(method->method_idnum());
++num_methods;
}
}
}
// Allocate result
objArrayOop r = oopFactory::new_objArray(klass, num_methods, CHECK_NULL);
objArrayHandle result (THREAD, r);
// Now just put the methods that we selected above, but go by their idnum // in case of redefinition. The methods can be redefined at any safepoint, // so above when allocating the oop array and below when creating reflect // objects. for (int i = 0; i < num_methods; i++) {
methodHandle method(THREAD, k->method_with_idnum(idnums->at(i))); if (method.is_null()) { // Method may have been deleted and seems this API can handle null // Otherwise should probably put a method that throws NSME
result->obj_at_put(i, NULL);
} else {
oop m; if (want_constructor) {
m = Reflection::new_constructor(method, CHECK_NULL);
} else {
m = Reflection::new_method(method, false, CHECK_NULL);
}
result->obj_at_put(i, m);
}
}
JVM_ENTRY(jclass, JVM_GetNestHost(JNIEnv* env, jclass current))
{ // current is not a primitive or array class
Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(current));
assert(c->is_instance_klass(), "must be");
InstanceKlass* ck = InstanceKlass::cast(c);
InstanceKlass* host = ck->nest_host(THREAD); return (jclass) (host == NULL ? NULL :
JNIHandles::make_local(THREAD, host->java_mirror()));
}
JVM_END
JVM_ENTRY(jobjectArray, JVM_GetNestMembers(JNIEnv* env, jclass current))
{ // current is not a primitive or array class
ResourceMark rm(THREAD);
Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(current));
assert(c->is_instance_klass(), "must be");
InstanceKlass* ck = InstanceKlass::cast(c);
InstanceKlass* host = ck->nest_host(THREAD);
log_trace(class, nestmates)("Calling GetNestMembers for type %s with nest-host %s",
ck->external_name(), host->external_name());
{
JvmtiVMObjectAllocEventCollector oam;
Array<u2>* members = host->nest_members(); int length = members == NULL ? 0 : members->length();
log_trace(class, nestmates)(" - host has %d listed nest members", length);
// nest host is first in the array so make it one bigger
objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(),
length + 1, CHECK_NULL);
objArrayHandle result(THREAD, r);
result->obj_at_put(0, host->java_mirror()); if (length != 0) { int count = 0; for (int i = 0; i < length; i++) { int cp_index = members->at(i);
Klass* k = host->constants()->klass_at(cp_index, THREAD); if (HAS_PENDING_EXCEPTION) { if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) { return NULL; // propagate VMEs
} if (log_is_enabled(Trace, class, nestmates)) {
stringStream ss; char* target_member_class = host->constants()->klass_name_at(cp_index)->as_C_string();
ss.print(" - resolution of nest member %s failed: ", target_member_class);
java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
log_trace(class, nestmates)("%s", ss.as_string());
}
CLEAR_PENDING_EXCEPTION; continue;
} if (k->is_instance_klass()) {
InstanceKlass* ik = InstanceKlass::cast(k);
InstanceKlass* nest_host_k = ik->nest_host(CHECK_NULL); if (nest_host_k == host) {
result->obj_at_put(count+1, k->java_mirror());
count++;
log_trace(class, nestmates)(" - [%d] = %s", count, ik->external_name());
} else {
log_trace(class, nestmates)(" - skipping member %s with different host %s",
ik->external_name(), nest_host_k->external_name());
}
} else {
log_trace(class, nestmates)(" - skipping member %s that is not an instance class",
k->external_name());
}
} if (count < length) { // we had invalid entries so we need to compact the array
log_trace(class, nestmates)(" - compacting array from length %d to %d",
length + 1, count + 1);
objArrayOop r2 = oopFactory::new_objArray(vmClasses::Class_klass(),
count + 1, CHECK_NULL);
objArrayHandle result2(THREAD, r2); for (int i = 0; i < count + 1; i++) {
result2->obj_at_put(i, result->obj_at(i));
} return (jobjectArray)JNIHandles::make_local(THREAD, result2());
}
} else {
assert(host == ck || ck->is_hidden(), "must be singleton nest or dynamic nestmate");
} return (jobjectArray)JNIHandles::make_local(THREAD, result());
}
}
JVM_END
JVM_ENTRY(jobjectArray, JVM_GetPermittedSubclasses(JNIEnv* env, jclass current))
{
oop mirror = JNIHandles::resolve_non_null(current);
assert(!java_lang_Class::is_primitive(mirror), "should not be");
Klass* c = java_lang_Class::as_Klass(mirror);
assert(c->is_instance_klass(), "must be");
InstanceKlass* ik = InstanceKlass::cast(c);
ResourceMark rm(THREAD);
log_trace(class, sealed)("Calling GetPermittedSubclasses for %s type %s",
ik->is_sealed() ? "sealed" : "non-sealed", ik->external_name()); if (ik->is_sealed()) {
JvmtiVMObjectAllocEventCollector oam;
Array<u2>* subclasses = ik->permitted_subclasses(); int length = subclasses->length();
log_trace(class, sealed)(" - sealed class has %d permitted subclasses", length);
objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(),
length, CHECK_NULL);
objArrayHandle result(THREAD, r); int count = 0; for (int i = 0; i < length; i++) { int cp_index = subclasses->at(i);
Klass* k = ik->constants()->klass_at(cp_index, THREAD); if (HAS_PENDING_EXCEPTION) { if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) { return NULL; // propagate VMEs
} if (log_is_enabled(Trace, class, sealed)) {
stringStream ss; char* permitted_subclass = ik->constants()->klass_name_at(cp_index)->as_C_string();
ss.print(" - resolution of permitted subclass %s failed: ", permitted_subclass);
java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
log_trace(class, sealed)("%s", ss.as_string());
}
CLEAR_PENDING_EXCEPTION; continue;
} if (k->is_instance_klass()) {
result->obj_at_put(count++, k->java_mirror());
log_trace(class, sealed)(" - [%d] = %s", count, k->external_name());
}
} if (count < length) { // we had invalid entries so we need to compact the array
objArrayOop r2 = oopFactory::new_objArray(vmClasses::Class_klass(),
count, CHECK_NULL);
objArrayHandle result2(THREAD, r2); for (int i = 0; i < count; i++) {
result2->obj_at_put(i, result->obj_at(i));
} return (jobjectArray)JNIHandles::make_local(THREAD, result2());
} return (jobjectArray)JNIHandles::make_local(THREAD, result());
} else { return NULL;
}
}
JVM_END
// Constant pool access //////////////////////////////////////////////////////////
JVM_ENTRY(jobject, JVM_GetClassConstantPool(JNIEnv *env, jclass cls))
{
JvmtiVMObjectAllocEventCollector oam;
oop mirror = JNIHandles::resolve_non_null(cls); // Return null for primitives and arrays if (!java_lang_Class::is_primitive(mirror)) {
Klass* k = java_lang_Class::as_Klass(mirror); if (k->is_instance_klass()) {
InstanceKlass* k_h = InstanceKlass::cast(k);
Handle jcp = reflect_ConstantPool::create(CHECK_NULL);
reflect_ConstantPool::set_cp(jcp(), k_h->constants()); return JNIHandles::make_local(THREAD, jcp());
}
} return NULL;
}
JVM_END
JVM_ENTRY(jint, JVM_ConstantPoolGetIntAt(JNIEnv *env, jobject obj, jobject unused, jint index))
{
constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
bounds_check(cp, index, CHECK_0);
constantTag tag = cp->tag_at(index); if (!tag.is_int()) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
} return cp->int_at(index);
}
JVM_END
JVM_ENTRY(jlong, JVM_ConstantPoolGetLongAt(JNIEnv *env, jobject obj, jobject unused, jint index))
{
constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
bounds_check(cp, index, CHECK_(0L));
constantTag tag = cp->tag_at(index); if (!tag.is_long()) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
} return cp->long_at(index);
}
JVM_END
JVM_ENTRY(jfloat, JVM_ConstantPoolGetFloatAt(JNIEnv *env, jobject obj, jobject unused, jint index))
{
constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
bounds_check(cp, index, CHECK_(0.0f));
constantTag tag = cp->tag_at(index); if (!tag.is_float()) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
} return cp->float_at(index);
}
JVM_END
JVM_ENTRY(jdouble, JVM_ConstantPoolGetDoubleAt(JNIEnv *env, jobject obj, jobject unused, jint index))
{
constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
bounds_check(cp, index, CHECK_(0.0));
constantTag tag = cp->tag_at(index); if (!tag.is_double()) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
} return cp->double_at(index);
}
JVM_END
JVM_ENTRY(jstring, JVM_ConstantPoolGetStringAt(JNIEnv *env, jobject obj, jobject unused, jint index))
{
constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
bounds_check(cp, index, CHECK_NULL);
constantTag tag = cp->tag_at(index); if (!tag.is_string()) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
}
oop str = cp->string_at(index, CHECK_NULL); return (jstring) JNIHandles::make_local(THREAD, str);
}
JVM_END
JVM_ENTRY(jstring, JVM_ConstantPoolGetUTF8At(JNIEnv *env, jobject obj, jobject unused, jint index))
{
JvmtiVMObjectAllocEventCollector oam;
constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
bounds_check(cp, index, CHECK_NULL);
constantTag tag = cp->tag_at(index); if (!tag.is_symbol()) {
THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
}
Symbol* sym = cp->symbol_at(index);
Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL); return (jstring) JNIHandles::make_local(THREAD, str());
}
JVM_END
JVM_ENTRY(jbyte, JVM_ConstantPoolGetTagAt(JNIEnv *env, jobject obj, jobject unused, jint index))
{
constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
bounds_check(cp, index, CHECK_0);
constantTag tag = cp->tag_at(index);
jbyte result = tag.value(); // If returned tag values are not from the JVM spec, e.g. tags from 100 to 105, // they are changed to the corresponding tags from the JVM spec, so that java code in // sun.reflect.ConstantPool will return only tags from the JVM spec, not internal ones. if (tag.is_klass_or_reference()) {
result = JVM_CONSTANT_Class;
} elseif (tag.is_string_index()) {
result = JVM_CONSTANT_String;
} elseif (tag.is_method_type_in_error()) {
result = JVM_CONSTANT_MethodType;
} elseif (tag.is_method_handle_in_error()) {
result = JVM_CONSTANT_MethodHandle;
} elseif (tag.is_dynamic_constant_in_error()) {
result = JVM_CONSTANT_Dynamic;
} return result;
}
JVM_END
oop r = JNIHandles::resolve(cls);
assert(! java_lang_Class::is_primitive(r), "primitive classes not allowed"); if (java_lang_Class::is_primitive(r)) returnfalse;
Klass* k = java_lang_Class::as_Klass(r);
assert(k->is_instance_klass(), "must be an instance klass"); if (!k->is_instance_klass()) returnfalse;
// Reflection for the verifier /////////////////////////////////////////////////////////////////
// RedefineClasses support: bug 6214132 caused verification to fail. // All functions from this section should call the jvmtiThreadSate function: // Klass* class_to_verify_considering_redefinition(Klass* klass). // The function returns a Klass* of the _scratch_class if the verifier // was invoked in the middle of the class redefinition. // Otherwise it returns its argument value which is the _the_class Klass*. // Please, refer to the description in the jvmtiThreadSate.hpp.
JVM_ENTRY(constchar*, JVM_GetClassNameUTF(JNIEnv *env, jclass cls))
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread); return k->name()->as_utf8();
JVM_END
JVM_ENTRY(void, JVM_GetClassCPTypes(JNIEnv *env, jclass cls, unsignedchar *types))
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread); // types will have length zero if this is not an InstanceKlass // (length is determined by call to JVM_GetClassCPEntriesCount) if (k->is_instance_klass()) {
ConstantPool* cp = InstanceKlass::cast(k)->constants(); for (int index = cp->length() - 1; index >= 0; index--) {
constantTag tag = cp->tag_at(index);
types[index] = (tag.is_unresolved_klass()) ? (unsignedchar) JVM_CONSTANT_Class : tag.value();
}
}
JVM_END
JVM_ENTRY(jint, JVM_GetClassCPEntriesCount(JNIEnv *env, jclass cls))
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread); return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->constants()->length();
JVM_END
JVM_ENTRY(jint, JVM_GetClassFieldsCount(JNIEnv *env, jclass cls))
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread); return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->java_fields_count();
JVM_END
JVM_ENTRY(jint, JVM_GetClassMethodsCount(JNIEnv *env, jclass cls))
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread); return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->methods()->length();
JVM_END
// The following methods, used for the verifier, are never called with // array klasses, so a direct cast to InstanceKlass is safe. // Typically, these methods are called in a loop with bounds determined // by the results of JVM_GetClass{Fields,Methods}Count, which return // zero for arrays.
JVM_ENTRY(void, JVM_GetMethodIxExceptionIndexes(JNIEnv *env, jclass cls, jint method_index, unsignedshort *exceptions))
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
Method* method = InstanceKlass::cast(k)->methods()->at(method_index); int length = method->checked_exceptions_length(); if (length > 0) {
CheckedExceptionElement* table= method->checked_exceptions_start(); for (int i = 0; i < length; i++) {
exceptions[i] = table[i].class_cp_index;
}
}
JVM_END
/** * All of these JVM_GetCP-xxx methods are used by the old verifier to * read entries in the constant pool. Since the old verifier always * works on a copy of the code, it will not see any rewriting that * may possibly occur in the middle of verification. So it is important * that nothing it calls tries to use the cpCache instead of the raw * constant pool, so we must use cp->uncached_x methods when appropriate.
*/
JVM_ENTRY(constchar*, JVM_GetCPFieldNameUTF(JNIEnv *env, jclass cls, jint cp_index))
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
ConstantPool* cp = InstanceKlass::cast(k)->constants(); switch (cp->tag_at(cp_index).value()) { case JVM_CONSTANT_Fieldref: return cp->uncached_name_ref_at(cp_index)->as_utf8(); default:
fatal("JVM_GetCPFieldNameUTF: illegal constant");
}
ShouldNotReachHere(); return NULL;
JVM_END
JVM_ENTRY(constchar*, JVM_GetCPMethodNameUTF(JNIEnv *env, jclass cls, jint cp_index))
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
ConstantPool* cp = InstanceKlass::cast(k)->constants(); switch (cp->tag_at(cp_index).value()) { case JVM_CONSTANT_InterfaceMethodref: case JVM_CONSTANT_Methodref: return cp->uncached_name_ref_at(cp_index)->as_utf8(); default:
fatal("JVM_GetCPMethodNameUTF: illegal constant");
}
ShouldNotReachHere(); return NULL;
JVM_END
JVM_ENTRY(constchar*, JVM_GetCPMethodSignatureUTF(JNIEnv *env, jclass cls, jint cp_index))
Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
ConstantPool* cp = InstanceKlass::cast(k)->constants(); switch (cp->tag_at(cp_index).value()) { case JVM_CONSTANT_InterfaceMethodref: case JVM_CONSTANT_Methodref: return cp->uncached_signature_ref_at(cp_index)->as_utf8(); default:
fatal("JVM_GetCPMethodSignatureUTF: illegal constant");
}
ShouldNotReachHere(); return NULL;
JVM_END
// Printing support ////////////////////////////////////////////////// extern"C" {
ATTRIBUTE_PRINTF(3, 0) int jio_vsnprintf(char *str, size_t count, constchar *fmt, va_list args) { // Reject count values that are negative signed values converted to // unsigned; see bug 4399518, 4417214 if ((intptr_t)count <= 0) return -1;
int result = os::vsnprintf(str, count, fmt, args); if (result > 0 && (size_t)result >= count) {
result = -1;
}
return result;
}
ATTRIBUTE_PRINTF(3, 4) int jio_snprintf(char *str, size_t count, constchar *fmt, ...) {
va_list args; int len;
va_start(args, fmt);
len = jio_vsnprintf(str, count, fmt, args);
va_end(args); return len;
}
ATTRIBUTE_PRINTF(2, 3) int jio_fprintf(FILE* f, constchar *fmt, ...) { int len;
va_list args;
va_start(args, fmt);
len = jio_vfprintf(f, fmt, args);
va_end(args); return len;
}
ATTRIBUTE_PRINTF(1, 2)
JNIEXPORT int jio_printf(constchar *fmt, ...) { int len;
va_list args;
va_start(args, fmt);
len = jio_vfprintf(defaultStream::output_stream(), fmt, args);
va_end(args); return len;
}
// HotSpot specific jio method void jio_print(constchar* s, size_t len) { // Try to make this function as atomic as possible. if (Arguments::vfprintf_hook() != NULL) {
jio_fprintf(defaultStream::output_stream(), "%.*s", (int)len, s);
} else { // Make an unused local variable to avoid warning from gcc compiler.
ssize_t count = os::write(defaultStream::output_fd(), s, (int)len);
}
}
// In most of the JVM thread support functions we need to access the // thread through a ThreadsListHandle to prevent it from exiting and // being reclaimed while we try to operate on it. The exceptions to this // rule are when operating on the current thread, or if the monitor of // the target java.lang.Thread is locked at the Java level - in both // cases the target cannot exit.
JVM_ENTRY(void, JVM_StartThread(JNIEnv* env, jobject jthread)) #if INCLUDE_CDS if (DumpSharedSpaces) { // During java -Xshare:dump, if we allow multiple Java threads to // execute in parallel, symbols and classes may be loaded in // random orders which will make the resulting CDS archive // non-deterministic. // // Lucikly, during java -Xshare:dump, it's important to run only // the code in the main Java thread (which is NOT started here) that // creates the module graph, etc. It's safe to not start the other // threads which are launched by class static initializers // (ReferenceHandler, FinalizerThread and CleanerImpl). if (log_is_enabled(Info, cds)) {
ResourceMark rm;
oop t = JNIHandles::resolve_non_null(jthread);
log_info(cds)("JVM_StartThread() ignored: %s", t->klass()->external_name());
} return;
} #endif
JavaThread *native_thread = NULL;
// We cannot hold the Threads_lock when we throw an exception, // due to rank ordering issues. Example: we might need to grab the // Heap_lock while we construct the exception. bool throw_illegal_thread_state = false;
// We must release the Threads_lock before we can post a jvmti event // in Thread::start.
{ // Ensure that the C++ Thread and OSThread structures aren't freed before // we operate.
MutexLocker mu(Threads_lock);
// Since JDK 5 the java.lang.Thread threadStatus is used to prevent // re-starting an already started thread, so we should usually find // that the JavaThread is null. However for a JNI attached thread // there is a small window between the Thread object being created // (with its JavaThread set) and the update to its threadStatus, so we // have to check for this if (java_lang_Thread::thread(JNIHandles::resolve_non_null(jthread)) != NULL) {
throw_illegal_thread_state = true;
} else {
jlong size =
java_lang_Thread::stackSize(JNIHandles::resolve_non_null(jthread)); // Allocate the C++ Thread structure and create the native thread. The // stack size retrieved from java is 64-bit signed, but the constructor takes // size_t (an unsigned type), which may be 32 or 64-bit depending on the platform. // - Avoid truncating on 32-bit platforms if size is greater than UINT_MAX. // - Avoid passing negative values which would result in really large stacks.
NOT_LP64(if (size > SIZE_MAX) size = SIZE_MAX;)
size_t sz = size > 0 ? (size_t) size : 0;
native_thread = new JavaThread(&thread_entry, sz);
// At this point it may be possible that no osthread was created for the // JavaThread due to lack of memory. Check for this situation and throw // an exception if necessary. Eventually we may want to change this so // that we only grab the lock if the thread was created successfully - // then we can also do this check and throw the exception in the // JavaThread constructor. if (native_thread->osthread() != NULL) { // Note: the current thread is not being used within "prepare".
native_thread->prepare(jthread);
}
}
}
if (throw_illegal_thread_state) { THROW(vmSymbols::java_lang_IllegalThreadStateException());
}
if (native_thread->osthread() == NULL) {
ResourceMark rm(thread);
log_warning(os, thread)("Failed to start the native thread for java.lang.Thread \"%s\"",
JavaThread::name_for(JNIHandles::resolve_non_null(jthread))); // No one should hold a reference to the 'native_thread'.
native_thread->smr_delete(); if (JvmtiExport::should_post_resource_exhausted()) {
JvmtiExport::post_resource_exhausted(
JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_THREADS,
os::native_thread_creation_failed_msg());
}
THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(),
os::native_thread_creation_failed_msg());
}
if (is_alive) { // jthread refers to a live JavaThread.
Thread::set_priority(receiver, (ThreadPriority)prio);
} // Implied else: If the JavaThread hasn't started yet, then the // priority set in the java.lang.Thread object above will be pushed // down when it does start.
JVM_END
JVM_ENTRY(void, JVM_Sleep(JNIEnv* env, jclass threadClass, jlong millis)) if (millis < 0) {
THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "timeout value is negative");
}
if (thread->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
THROW_MSG(vmSymbols::java_lang_InterruptedException(), "sleep interrupted");
}
// Save current thread state and restore it at the end of this block. // And set new thread state to SLEEPING.
JavaThreadSleepState jtss(thread);
HOTSPOT_THREAD_SLEEP_BEGIN(millis);
if (millis == 0) {
os::naked_yield();
} else {
ThreadState old_state = thread->osthread()->get_state();
thread->osthread()->set_state(SLEEPING); if (!thread->sleep(millis)) { // interrupted // An asynchronous exception could have been thrown on // us while we were sleeping. We do not overwrite those. if (!HAS_PENDING_EXCEPTION) {
HOTSPOT_THREAD_SLEEP_END(1);
// TODO-FIXME: THROW_MSG returns which means we will not call set_state() // to properly restore the thread state. That's likely wrong.
THROW_MSG(vmSymbols::java_lang_InterruptedException(), "sleep interrupted");
}
}
thread->osthread()->set_state(old_state);
}
HOTSPOT_THREAD_SLEEP_END(0);
JVM_END
JVM_ENTRY(jobject, JVM_CurrentCarrierThread(JNIEnv* env, jclass threadClass))
oop jthread = thread->threadObj();
assert(jthread != NULL, "no current carrier thread!"); return JNIHandles::make_local(THREAD, jthread);
JVM_END
JVM_ENTRY(jobject, JVM_CurrentThread(JNIEnv* env, jclass threadClass))
oop theThread = thread->vthread();
assert(theThread != (oop)NULL, "no current thread!"); return JNIHandles::make_local(THREAD, theThread);
JVM_END
JVM_ENTRY(void, JVM_SetNativeThreadName(JNIEnv* env, jobject jthread, jstring name)) // We don't use a ThreadsListHandle here because the current thread // must be alive.
oop java_thread = JNIHandles::resolve_non_null(jthread);
JavaThread* thr = java_lang_Thread::thread(java_thread); if (thread == thr && !thr->has_attached_via_jni()) { // Thread naming is only supported for the current thread and // we don't set the name of an attached thread to avoid stepping // on other programs.
ResourceMark rm(thread); constchar *thread_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
os::set_native_thread_name(thread_name);
}
JVM_END
if (vmClasses::reflect_CallerSensitive_klass() != NULL) { // This must only be called from SecurityManager.getClassContext
Method* m = vfst.method(); if (!(m->method_holder() == vmClasses::SecurityManager_klass() &&
m->name() == vmSymbols::getClassContext_name() &&
m->signature() == vmSymbols::void_class_array_signature())) {
THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "JVM_GetClassContext must only be called from SecurityManager.getClassContext");
}
}
// Collect method holders
GrowableArray<Klass*>* klass_array = new GrowableArray<Klass*>(); for (; !vfst.at_end(); vfst.security_next()) {
Method* m = vfst.method(); // Native frames are not returned if (!m->is_ignored_by_security_stack_walk() && !m->is_native()) {
Klass* holder = m->method_holder();
assert(holder->is_klass(), "just checking");
klass_array->append(holder);
}
}
// Create result array of type [Ljava/lang/Class;
objArrayOop result = oopFactory::new_objArray(vmClasses::Class_klass(), klass_array->length(), CHECK_NULL); // Fill in mirrors corresponding to method holders for (int i = 0; i < klass_array->length(); i++) {
result->obj_at_put(i, klass_array->at(i)->java_mirror());
}
JVM_ENTRY(void, JVM_ReferenceClear(JNIEnv* env, jobject ref))
oop ref_oop = JNIHandles::resolve_non_null(ref); // FinalReference has it's own implementation of clear().
assert(!java_lang_ref_Reference::is_final(ref_oop), "precondition"); if (java_lang_ref_Reference::unknown_referent_no_keepalive(ref_oop) == NULL) { // If the referent has already been cleared then done. // However, if the referent is dead but has not yet been cleared by // concurrent reference processing, it should NOT be cleared here. // Instead, clearing should be left to the GC. Clearing it here could // detectably lose an expected notification, which is impossible with // STW reference processing. The clearing in enqueue() doesn't have // this problem, since the enqueue covers the notification, but it's not // worth the effort to handle that case specially. return;
}
java_lang_ref_Reference::clear_referent(ref_oop);
JVM_END
// Return the first user-defined class loader up the execution stack, or null // if only code from the bootstrap or platform class loader is on the stack.
JVM_ENTRY(jobject, JVM_LatestUserDefinedLoader(JNIEnv *env)) for (vframeStream vfst(thread); !vfst.at_end(); vfst.next()) {
InstanceKlass* ik = vfst.method()->method_holder();
oop loader = ik->class_loader(); if (loader != NULL && !SystemDictionary::is_platform_class_loader(loader)) { // Skip reflection related frames if (!ik->is_subclass_of(vmClasses::reflect_MethodAccessorImpl_klass()) &&
!ik->is_subclass_of(vmClasses::reflect_ConstructorAccessorImpl_klass())) { return JNIHandles::make_local(THREAD, loader);
}
}
} return NULL;
JVM_END
JVM_ENTRY(jvalue, JVM_GetPrimitiveArrayElement(JNIEnv *env, jobject arr, jint index, jint wCode))
jvalue value;
value.i = 0; // to initialize value before getting used in CHECK
arrayOop a = check_array(env, arr, true, CHECK_(value));
assert(a->is_typeArray(), "just checking");
BasicType type = Reflection::array_get(&value, a, index, CHECK_(value));
BasicType wide_type = (BasicType) wCode; if (type != wide_type) {
Reflection::widen(&value, type, wide_type, CHECK_(value));
} return value;
JVM_END
JVM_ENTRY(void, JVM_SetArrayElement(JNIEnv *env, jobject arr, jint index, jobject val))
arrayOop a = check_array(env, arr, false, CHECK);
oop box = JNIHandles::resolve(val);
jvalue value;
value.i = 0; // to initialize value before getting used in CHECK
BasicType value_type; if (a->is_objArray()) { // Make sure we do no unbox e.g. java/lang/Integer instances when storing into an object array
value_type = Reflection::unbox_for_regular_object(box, &value);
} else {
value_type = Reflection::unbox_for_primitive(box, &value, CHECK);
}
Reflection::array_set(&value, a, index, value_type, CHECK);
JVM_END
// VM Raw monitor support //////////////////////////////////////////////////////////////////////
// VM Raw monitors (not to be confused with JvmtiRawMonitors) are a simple mutual exclusion // lock (not actually monitors: no wait/notify) that is exported by the VM for use by JDK // library code. They may be used by JavaThreads and non-JavaThreads and do not participate // in the safepoint protocol, thread suspension, thread interruption, or anything of that // nature. JavaThreads will be "in native" when using this API from JDK code.
jclass find_class_from_class_loader(JNIEnv* env, Symbol* name, jboolean init,
Handle loader, Handle protection_domain,
jboolean throwError, TRAPS) { // Security Note: // The Java level wrapper will perform the necessary security check allowing // us to pass the NULL as the initiating class loader. The VM is responsible for // the checkPackageAccess relative to the initiating class loader via the // protection_domain. The protection_domain is passed as NULL by the java code // if there is no security manager in 3-arg Class.forName().
Klass* klass = SystemDictionary::resolve_or_fail(name, loader, protection_domain, throwError != 0, CHECK_NULL);
// Check if we should initialize the class if (init && klass->is_instance_klass()) {
klass->initialize(CHECK_NULL);
} return (jclass) JNIHandles::make_local(THREAD, klass->java_mirror());
}
Klass* caller_k = java_lang_Class::as_Klass(JNIHandles::resolve(caller));
InstanceKlass* caller_ik = InstanceKlass::cast(caller_k); if (caller_ik->is_hidden()) { // Hidden classes not of type lambda proxy classes are currently not being archived. // If the caller_ik is of one of the above types, the corresponding lambda proxy class won't be // registered for archiving. return;
}
Klass* lambda_k = java_lang_Class::as_Klass(JNIHandles::resolve(lambdaProxyClass));
InstanceKlass* lambda_ik = InstanceKlass::cast(lambda_k);
assert(lambda_ik->is_hidden(), "must be a hidden class");
assert(!lambda_ik->is_non_strong_hidden(), "expected a strong hidden class");
Klass* caller_k = java_lang_Class::as_Klass(JNIHandles::resolve(caller));
InstanceKlass* caller_ik = InstanceKlass::cast(caller_k); if (!caller_ik->is_shared()) { // there won't be a shared lambda class if the caller_ik is not in the shared archive. return NULL;
}
JVM_ENTRY(void, JVM_LogLambdaFormInvoker(JNIEnv *env, jstring line)) #if INCLUDE_CDS
assert(ClassListWriter::is_enabled() || DynamicDumpSharedSpaces, "Should be set and open or do dynamic dump"); if (line != NULL) {
ResourceMark rm(THREAD);
Handle h_line (THREAD, JNIHandles::resolve_non_null(line)); char* c_line = java_lang_String::as_utf8_string(h_line()); if (DynamicDumpSharedSpaces) { // Note: LambdaFormInvokers::append take same format which is not // same as below the print format. The line does not include LAMBDA_FORM_TAG.
LambdaFormInvokers::append(os::strdup((constchar*)c_line, mtInternal));
} if (ClassListWriter::is_enabled()) {
ClassListWriter w;
w.stream()->print_cr("%s %s", LAMBDA_FORM_TAG, c_line);
}
} #endif// INCLUDE_CDS
JVM_END
// Support for java.lang.Thread.getStackTrace() and getAllStackTraces() methods // Return StackTraceElement[][], each element is the stack trace of a thread in // the corresponding entry in the given threads array
JVM_ENTRY(jobjectArray, JVM_DumpThreads(JNIEnv *env, jclass threadClass, jobjectArray threads))
JvmtiVMObjectAllocEventCollector oam;
// Check if threads is null if (threads == NULL) {
THROW_(vmSymbols::java_lang_NullPointerException(), 0);
}
objArrayOop a = objArrayOop(JNIHandles::resolve_non_null(threads));
objArrayHandle ah(THREAD, a); int num_threads = ah->length(); // check if threads is non-empty array if (num_threads == 0) {
THROW_(vmSymbols::java_lang_IllegalArgumentException(), 0);
}
// check if threads is not an array of objects of Thread class
Klass* k = ObjArrayKlass::cast(ah->klass())->element_klass(); if (k != vmClasses::Thread_klass()) {
THROW_(vmSymbols::java_lang_IllegalArgumentException(), 0);
}
ResourceMark rm(THREAD);
GrowableArray<instanceHandle>* thread_handle_array = new GrowableArray<instanceHandle>(num_threads); for (int i = 0; i < num_threads; i++) {
oop thread_obj = ah->obj_at(i);
instanceHandle h(THREAD, (instanceOop) thread_obj);
thread_handle_array->append(h);
}
// The JavaThread references in thread_handle_array are validated // in VM_ThreadDump::doit().
Handle stacktraces = ThreadService::dump_stack_traces(thread_handle_array, num_threads, CHECK_NULL); return (jobjectArray)JNIHandles::make_local(THREAD, stacktraces());
JVM_END
// JVM monitoring and management support
JVM_LEAF(void*, JVM_GetManagement(jint version)) return Management::get_jmm_interface(version);
JVM_END
// com.sun.tools.attach.VirtualMachine agent properties support // // Initialize the agent properties with the properties maintained in the VM
JVM_ENTRY(jobject, JVM_InitAgentProperties(JNIEnv *env, jobject properties))
ResourceMark rm;
if (ofClass == NULL) { return NULL;
}
Handle mirror(THREAD, JNIHandles::resolve_non_null(ofClass)); // Special handling for primitive objects if (java_lang_Class::is_primitive(mirror())) { return NULL;
}
Klass* k = java_lang_Class::as_Klass(mirror()); if (!k->is_instance_klass()) { return NULL;
}
InstanceKlass* ik = InstanceKlass::cast(k); int encl_method_class_idx = ik->enclosing_method_class_index(); if (encl_method_class_idx == 0) { return NULL;
}
objArrayOop dest_o = oopFactory::new_objArray(vmClasses::Object_klass(), 3, CHECK_NULL);
objArrayHandle dest(THREAD, dest_o);
Klass* enc_k = ik->constants()->klass_at(encl_method_class_idx, CHECK_NULL);
dest->obj_at_put(0, enc_k->java_mirror()); int encl_method_method_idx = ik->enclosing_method_method_index(); if (encl_method_method_idx != 0) {
Symbol* sym = ik->constants()->symbol_at(
extract_low_short_from_int(
ik->constants()->name_and_type_at(encl_method_method_idx)));
Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
dest->obj_at_put(1, str());
sym = ik->constants()->symbol_at(
extract_high_short_from_int(
ik->constants()->name_and_type_at(encl_method_method_idx)));
str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
dest->obj_at_put(2, str());
} return (jobjectArray) JNIHandles::make_local(THREAD, dest());
}
JVM_END
// Returns an array of java.lang.String objects containing the input arguments to the VM.
JVM_ENTRY(jobjectArray, JVM_GetVmArguments(JNIEnv *env))
ResourceMark rm(THREAD);
if (JvmtiExport::should_post_vthread_unmount()) {
JvmtiExport::post_vthread_unmount(vthread);
} if (last_unmount) { if (JvmtiExport::can_support_virtual_threads()) { if (JvmtiExport::should_post_vthread_end()) {
JvmtiExport::post_vthread_end(vthread);
}
} else { // compatibility for vthread unaware agents: legacy thread_end if (PostVirtualThreadCompatibleLifecycleEvents &&
JvmtiExport::should_post_thread_life()) {
JvmtiExport::post_thread_end(thread);
}
}
}
assert(!thread->is_in_tmp_VTMS_transition(), "sanity check");
assert(!thread->is_in_VTMS_transition(), "sanity check");
JvmtiVTMSTransitionDisabler::start_VTMS_transition(vthread, /* is_mount */ false);
if (last_unmount && thread->jvmti_thread_state() != NULL) {
JvmtiExport::cleanup_thread(thread);
thread->set_jvmti_thread_state(NULL);
oop vt = JNIHandles::resolve(vthread);
java_lang_Thread::set_jvmti_thread_state(vt, NULL);
}
thread->rebind_to_jvmti_thread_state_of(ct()); #else
fatal("Should only be called with JVMTI enabled"); #endif
JVM_END
JVM_ENTRY(void, JVM_VirtualThreadUnmountEnd(JNIEnv* env, jobject vthread, jboolean last_unmount)) #if INCLUDE_JVMTI if (!DoJVMTIVirtualThreadTransitions) {
assert(!JvmtiExport::can_support_virtual_threads(), "sanity check"); return;
}
assert(thread->is_in_VTMS_transition(), "sanity check");
assert(!thread->is_in_tmp_VTMS_transition(), "sanity check");
JvmtiVTMSTransitionDisabler::finish_VTMS_transition(vthread, /* is_mount */ false); #else
fatal("Should only be called with JVMTI enabled"); #endif
JVM_END
JVM_ENTRY(void, JVM_VirtualThreadHideFrames(JNIEnv* env, jobject vthread, jboolean hide)) #if INCLUDE_JVMTI if (!DoJVMTIVirtualThreadTransitions) {
assert(!JvmtiExport::can_support_virtual_threads(), "sanity check"); return;
}
assert(!thread->is_in_VTMS_transition(), "sanity check");
assert(thread->is_in_tmp_VTMS_transition() != (bool)hide, "sanity check");
thread->toggle_is_in_tmp_VTMS_transition(); #else
fatal("Should only be called with JVMTI enabled"); #endif
JVM_END
/* * Return the current class's class file version. The low order 16 bits of the * returned jint contain the class's major version. The high order 16 bits * contain the class's minor version.
*/
JVM_ENTRY(jint, JVM_GetClassFileVersion(JNIEnv* env, jclass current))
oop mirror = JNIHandles::resolve_non_null(current); if (java_lang_Class::is_primitive(mirror)) { // return latest major version and minor version of 0. return JVM_CLASSFILE_MAJOR_VERSION;
}
assert(!java_lang_Class::as_Klass(mirror)->is_array_klass(), "unexpected array class");
Klass* c = java_lang_Class::as_Klass(mirror);
assert(c->is_instance_klass(), "must be");
InstanceKlass* ik = InstanceKlass::cast(c); return (ik->minor_version() << 16) | ik->major_version();
JVM_END
/* * Ensure that code doing a stackwalk and using javaVFrame::locals() to * get the value will see a materialized value and not a scalar-replaced * null value.
*/
JVM_ENTRY(void, JVM_EnsureMaterializedForStackWalk_func(JNIEnv* env, jobject vthread, jobject value))
JVM_EnsureMaterializedForStackWalk(env, value);
JVM_END
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.93 Sekunden
(vorverarbeitet am 2026-05-02)
¤
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