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/*
* Copyright (c) 1997, 2018, 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.
*
*/
#include "precompiled.hpp"
#include "classfile/classLoaderData.inline.hpp"
#include "classfile/dictionary.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/vmSymbols.hpp"
#include "gc/shared/collectedHeap.inline.hpp"
#include "logging/log.hpp"
#include "memory/heapInspection.hpp"
#include "memory/metadataFactory.hpp"
#include "memory/metaspaceClosure.hpp"
#include "memory/metaspaceShared.hpp"
#include "memory/oopFactory.hpp"
#include "memory/resourceArea.hpp"
#include "oops/compressedOops.inline.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/klass.inline.hpp"
#include "oops/oop.inline.hpp"
#include "oops/oopHandle.inline.hpp"
#include "runtime/atomic.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/orderAccess.hpp"
#include "utilities/macros.hpp"
#include "utilities/stack.inline.hpp"
void Klass::set_java_mirror(Handle m) {
assert(!m.is_null(), "New mirror should never be null.");
assert(_java_mirror.resolve() == NULL, "should only be used to initialize mirror");
_java_mirror = class_loader_data()->add_handle(m);
}
oop Klass::java_mirror() const {
return _java_mirror.resolve();
}
oop Klass::java_mirror_no_keepalive() const {
return _java_mirror.peek();
}
bool Klass::is_cloneable() const {
return _access_flags.is_cloneable_fast() ||
is_subtype_of(SystemDictionary::Cloneable_klass());
}
void Klass::set_is_cloneable() {
if (name() == vmSymbols::java_lang_invoke_MemberName()) {
assert(is_final(), "no subclasses allowed");
// MemberName cloning should not be intrinsified and always happen in JVM_Clone.
} else if (is_instance_klass() && InstanceKlass::cast(this)->reference_type() != REF_NONE) {
// Reference cloning should not be intrinsified and always happen in JVM_Clone.
} else {
_access_flags.set_is_cloneable_fast();
}
}
void Klass::set_name(Symbol* n) {
_name = n;
if (_name != NULL) _name->increment_refcount();
}
bool Klass::is_subclass_of(const Klass* k) const {
// Run up the super chain and check
if (this == k) return true;
Klass* t = const_cast<Klass*>(this)->super();
while (t != NULL) {
if (t == k) return true;
t = t->super();
}
return false;
}
bool Klass::search_secondary_supers(Klass* k) const {
// Put some extra logic here out-of-line, before the search proper.
// This cuts down the size of the inline method.
// This is necessary, since I am never in my own secondary_super list.
if (this == k)
return true;
// Scan the array-of-objects for a match
int cnt = secondary_supers()->length();
for (int i = 0; i < cnt; i++) {
if (secondary_supers()->at(i) == k) {
((Klass*)this)->set_secondary_super_cache(k);
return true;
}
}
return false;
}
// Return self, except for abstract classes with exactly 1
// implementor. Then return the 1 concrete implementation.
Klass *Klass::up_cast_abstract() {
Klass *r = this;
while( r->is_abstract() ) { // Receiver is abstract?
Klass *s = r->subklass(); // Check for exactly 1 subklass
if( !s || s->next_sibling() ) // Oops; wrong count; give up
return this; // Return 'this' as a no-progress flag
r = s; // Loop till find concrete class
}
return r; // Return the 1 concrete class
}
// Find LCA in class hierarchy
Klass *Klass::LCA( Klass *k2 ) {
Klass *k1 = this;
while( 1 ) {
if( k1->is_subtype_of(k2) ) return k2;
if( k2->is_subtype_of(k1) ) return k1;
k1 = k1->super();
k2 = k2->super();
}
}
void Klass::check_valid_for_instantiation(bool throwError, TRAPS) {
ResourceMark rm(THREAD);
THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
: vmSymbols::java_lang_InstantiationException(), external_name());
}
void Klass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) {
ResourceMark rm(THREAD);
assert(s != NULL, "Throw NPE!");
THROW_MSG(vmSymbols::java_lang_ArrayStoreException(),
err_msg("arraycopy: source type %s is not an array", s->klass()->external_name()));
}
void Klass::initialize(TRAPS) {
ShouldNotReachHere();
}
bool Klass::compute_is_subtype_of(Klass* k) {
assert(k->is_klass(), "argument must be a class");
return is_subclass_of(k);
}
Klass* Klass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
#ifdef ASSERT
tty->print_cr("Error: find_field called on a klass oop."
" Likely error: reflection method does not correctly"
" wrap return value in a mirror object.");
#endif
ShouldNotReachHere();
return NULL;
}
Method* Klass::uncached_lookup_method(const Symbol* name, const Symbol* signature,
OverpassLookupMode overpass_mode,
PrivateLookupMode private_mode) const {
#ifdef ASSERT
tty->print_cr("Error: uncached_lookup_method called on a klass oop."
" Likely error: reflection method does not correctly"
" wrap return value in a mirror object.");
#endif
ShouldNotReachHere();
return NULL;
}
void* Klass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw() {
return Metaspace::allocate(loader_data, word_size, MetaspaceObj::ClassType, THREAD);
}
// "Normal" instantiation is preceeded by a MetaspaceObj allocation
// which zeros out memory - calloc equivalent.
// The constructor is also used from CppVtableCloner,
// which doesn't zero out the memory before calling the constructor.
// Need to set the _java_mirror field explicitly to not hit an assert that the field
// should be NULL before setting it.
Klass::Klass(KlassID id) : _id(id),
_prototype_header(markOopDesc::prototype()),
_shared_class_path_index(-1),
_java_mirror(NULL) {
CDS_ONLY(_shared_class_flags = 0;)
CDS_JAVA_HEAP_ONLY(_archived_mirror = 0;)
_primary_supers[0] = this;
set_super_check_offset(in_bytes(primary_supers_offset()));
}
jint Klass::array_layout_helper(BasicType etype) {
assert(etype >= T_BOOLEAN && etype <= T_OBJECT, "valid etype");
// Note that T_ARRAY is not allowed here.
int hsize = arrayOopDesc::base_offset_in_bytes(etype);
int esize = type2aelembytes(etype);
bool isobj = (etype == T_OBJECT);
int tag = isobj ? _lh_array_tag_obj_value : _lh_array_tag_type_value;
int lh = array_layout_helper(tag, hsize, etype, exact_log2(esize));
assert(lh < (int)_lh_neutral_value, "must look like an array layout");
assert(layout_helper_is_array(lh), "correct kind");
assert(layout_helper_is_objArray(lh) == isobj, "correct kind");
assert(layout_helper_is_typeArray(lh) == !isobj, "correct kind");
assert(layout_helper_header_size(lh) == hsize, "correct decode");
assert(layout_helper_element_type(lh) == etype, "correct decode");
assert(1 << layout_helper_log2_element_size(lh) == esize, "correct decode");
return lh;
}
bool Klass::can_be_primary_super_slow() const {
if (super() == NULL)
return true;
else if (super()->super_depth() >= primary_super_limit()-1)
return false;
else
return true;
}
void Klass::initialize_supers(Klass* k, Array<Klass*>* transitive_interfaces, TRAPS) {
if (FastSuperclassLimit == 0) {
// None of the other machinery matters.
set_super(k);
return;
}
if (k == NULL) {
set_super(NULL);
_primary_supers[0] = this;
assert(super_depth() == 0, "Object must already be initialized properly");
} else if (k != super() || k == SystemDictionary::Object_klass()) {
assert(super() == NULL || super() == SystemDictionary::Object_klass(),
"initialize this only once to a non-trivial value");
set_super(k);
Klass* sup = k;
int sup_depth = sup->super_depth();
juint my_depth = MIN2(sup_depth + 1, (int)primary_super_limit());
if (!can_be_primary_super_slow())
my_depth = primary_super_limit();
for (juint i = 0; i < my_depth; i++) {
_primary_supers[i] = sup->_primary_supers[i];
}
Klass* *super_check_cell;
if (my_depth < primary_super_limit()) {
_primary_supers[my_depth] = this;
super_check_cell = &_primary_supers[my_depth];
} else {
// Overflow of the primary_supers array forces me to be secondary.
super_check_cell = &_secondary_super_cache;
}
set_super_check_offset((address)super_check_cell - (address) this);
#ifdef ASSERT
{
juint j = super_depth();
assert(j == my_depth, "computed accessor gets right answer");
Klass* t = this;
while (!t->can_be_primary_super()) {
t = t->super();
j = t->super_depth();
}
for (juint j1 = j+1; j1 < primary_super_limit(); j1++) {
assert(primary_super_of_depth(j1) == NULL, "super list padding");
}
while (t != NULL) {
assert(primary_super_of_depth(j) == t, "super list initialization");
t = t->super();
--j;
}
assert(j == (juint)-1, "correct depth count");
}
#endif
}
if (secondary_supers() == NULL) {
// Now compute the list of secondary supertypes.
// Secondaries can occasionally be on the super chain,
// if the inline "_primary_supers" array overflows.
int extras = 0;
Klass* p;
for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
++extras;
}
ResourceMark rm(THREAD); // need to reclaim GrowableArrays allocated below
// Compute the "real" non-extra secondaries.
GrowableArray<Klass*>* secondaries = compute_secondary_supers(extras, transitive_interfaces);
if (secondaries == NULL) {
// secondary_supers set by compute_secondary_supers
return;
}
GrowableArray<Klass*>* primaries = new GrowableArray<Klass*>(extras);
for (p = super(); !(p == NULL || p->can_be_primary_super()); p = p->super()) {
int i; // Scan for overflow primaries being duplicates of 2nd'arys
// This happens frequently for very deeply nested arrays: the
// primary superclass chain overflows into the secondary. The
// secondary list contains the element_klass's secondaries with
// an extra array dimension added. If the element_klass's
// secondary list already contains some primary overflows, they
// (with the extra level of array-ness) will collide with the
// normal primary superclass overflows.
for( i = 0; i < secondaries->length(); i++ ) {
if( secondaries->at(i) == p )
break;
}
if( i < secondaries->length() )
continue; // It's a dup, don't put it in
primaries->push(p);
}
// Combine the two arrays into a metadata object to pack the array.
// The primaries are added in the reverse order, then the secondaries.
int new_length = primaries->length() + secondaries->length();
Array<Klass*>* s2 = MetadataFactory::new_array<Klass*>(
class_loader_data(), new_length, CHECK);
int fill_p = primaries->length();
for (int j = 0; j < fill_p; j++) {
s2->at_put(j, primaries->pop()); // add primaries in reverse order.
}
for( int j = 0; j < secondaries->length(); j++ ) {
s2->at_put(j+fill_p, secondaries->at(j)); // add secondaries on the end.
}
#ifdef ASSERT
// We must not copy any NULL placeholders left over from bootstrap.
for (int j = 0; j < s2->length(); j++) {
assert(s2->at(j) != NULL, "correct bootstrapping order");
}
#endif
set_secondary_supers(s2);
}
}
GrowableArray<Klass*>* Klass::compute_secondary_supers(int num_extra_slots,
Array<Klass*>* transitive_interfaces) {
assert(num_extra_slots == 0, "override for complex klasses");
assert(transitive_interfaces == NULL, "sanity");
set_secondary_supers(Universe::the_empty_klass_array());
return NULL;
}
InstanceKlass* Klass::superklass() const {
assert(super() == NULL || super()->is_instance_klass(), "must be instance klass");
return _super == NULL ? NULL : InstanceKlass::cast(_super);
}
void Klass::set_subklass(Klass* s) {
assert(s != this, "sanity check");
_subklass = s;
}
void Klass::set_next_sibling(Klass* s) {
assert(s != this, "sanity check");
_next_sibling = s;
}
void Klass::append_to_sibling_list() {
debug_only(verify();)
// add ourselves to superklass' subklass list
InstanceKlass* super = superklass();
if (super == NULL) return; // special case: class Object
assert((!super->is_interface() // interfaces cannot be supers
&& (super->superklass() == NULL || !is_interface())),
"an interface can only be a subklass of Object");
Klass* prev_first_subklass = super->subklass();
if (prev_first_subklass != NULL) {
// set our sibling to be the superklass' previous first subklass
set_next_sibling(prev_first_subklass);
}
// make ourselves the superklass' first subklass
super->set_subklass(this);
debug_only(verify();)
}
oop Klass::holder_phantom() const {
return class_loader_data()->holder_phantom();
}
void Klass::clean_weak_klass_links(bool unloading_occurred, bool clean_alive_klasses) {
if (!ClassUnloading || !unloading_occurred) {
return;
}
Klass* root = SystemDictionary::Object_klass();
Stack<Klass*, mtGC> stack;
stack.push(root);
while (!stack.is_empty()) {
Klass* current = stack.pop();
assert(current->is_loader_alive(), "just checking, this should be live");
// Find and set the first alive subklass
Klass* sub = current->subklass();
while (sub != NULL && !sub->is_loader_alive()) {
#ifndef PRODUCT
if (log_is_enabled(Trace, class, unload)) {
ResourceMark rm;
log_trace(class, unload)("unlinking class (subclass): %s", sub->external_name());
}
#endif
sub = sub->next_sibling();
}
current->set_subklass(sub);
if (sub != NULL) {
stack.push(sub);
}
// Find and set the first alive sibling
Klass* sibling = current->next_sibling();
while (sibling != NULL && !sibling->is_loader_alive()) {
if (log_is_enabled(Trace, class, unload)) {
ResourceMark rm;
log_trace(class, unload)("[Unlinking class (sibling) %s]", sibling->external_name());
}
sibling = sibling->next_sibling();
}
current->set_next_sibling(sibling);
if (sibling != NULL) {
stack.push(sibling);
}
// Clean the implementors list and method data.
if (clean_alive_klasses && current->is_instance_klass()) {
InstanceKlass* ik = InstanceKlass::cast(current);
ik->clean_weak_instanceklass_links();
// JVMTI RedefineClasses creates previous versions that are not in
// the class hierarchy, so process them here.
while ((ik = ik->previous_versions()) != NULL) {
ik->clean_weak_instanceklass_links();
}
}
}
}
void Klass::metaspace_pointers_do(MetaspaceClosure* it) {
if (log_is_enabled(Trace, cds)) {
ResourceMark rm;
log_trace(cds)("Iter(Klass): %p (%s)", this, external_name());
}
it->push(&_name);
it->push(&_secondary_super_cache);
it->push(&_secondary_supers);
for (int i = 0; i < _primary_super_limit; i++) {
it->push(&_primary_supers[i]);
}
it->push(&_super);
it->push(&_subklass);
it->push(&_next_sibling);
it->push(&_next_link);
vtableEntry* vt = start_of_vtable();
for (int i=0; i<vtable_length(); i++) {
it->push(vt[i].method_addr());
}
}
void Klass::remove_unshareable_info() {
assert (DumpSharedSpaces, "only called for DumpSharedSpaces");
JFR_ONLY(REMOVE_ID(this);)
if (log_is_enabled(Trace, cds, unshareable)) {
ResourceMark rm;
log_trace(cds, unshareable)("remove: %s", external_name());
}
set_subklass(NULL);
set_next_sibling(NULL);
set_next_link(NULL);
// Null out class_loader_data because we don't share that yet.
set_class_loader_data(NULL);
set_is_shared();
}
void Klass::remove_java_mirror() {
assert (DumpSharedSpaces, "only called for DumpSharedSpaces");
if (log_is_enabled(Trace, cds, unshareable)) {
ResourceMark rm;
log_trace(cds, unshareable)("remove java_mirror: %s", external_name());
}
// Just null out the mirror. The class_loader_data() no longer exists.
_java_mirror = NULL;
}
void Klass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
assert(is_klass(), "ensure C++ vtable is restored");
assert(is_shared(), "must be set");
JFR_ONLY(RESTORE_ID(this);)
if (log_is_enabled(Trace, cds, unshareable)) {
ResourceMark rm;
log_trace(cds, unshareable)("restore: %s", external_name());
}
// If an exception happened during CDS restore, some of these fields may already be
// set. We leave the class on the CLD list, even if incomplete so that we don't
// modify the CLD list outside a safepoint.
if (class_loader_data() == NULL) {
// Restore class_loader_data to the null class loader data
set_class_loader_data(loader_data);
// Add to null class loader list first before creating the mirror
// (same order as class file parsing)
loader_data->add_class(this);
}
Handle loader(THREAD, loader_data->class_loader());
ModuleEntry* module_entry = NULL;
Klass* k = this;
if (k->is_objArray_klass()) {
k = ObjArrayKlass::cast(k)->bottom_klass();
}
// Obtain klass' module.
if (k->is_instance_klass()) {
InstanceKlass* ik = (InstanceKlass*) k;
module_entry = ik->module();
} else {
module_entry = ModuleEntryTable::javabase_moduleEntry();
}
// Obtain java.lang.Module, if available
Handle module_handle(THREAD, ((module_entry != NULL) ? module_entry->module() : (oop)NULL));
if (this->has_raw_archived_mirror()) {
ResourceMark rm;
log_debug(cds, mirror)("%s has raw archived mirror", external_name());
if (MetaspaceShared::open_archive_heap_region_mapped()) {
bool present = java_lang_Class::restore_archived_mirror(this, loader, module_handle,
protection_domain,
CHECK);
if (present) {
return;
}
}
// No archived mirror data
log_debug(cds, mirror)("No archived mirror data for %s", external_name());
_java_mirror = NULL;
this->clear_has_raw_archived_mirror();
}
// Only recreate it if not present. A previous attempt to restore may have
// gotten an OOM later but keep the mirror if it was created.
if (java_mirror() == NULL) {
log_trace(cds, mirror)("Recreate mirror for %s", external_name());
java_lang_Class::create_mirror(this, loader, module_handle, protection_domain, CHECK);
}
}
#if INCLUDE_CDS_JAVA_HEAP
// Used at CDS dump time to access the archived mirror. No GC barrier.
oop Klass::archived_java_mirror_raw() {
assert(has_raw_archived_mirror(), "must have raw archived mirror");
return CompressedOops::decode(_archived_mirror);
}
// No GC barrier
void Klass::set_archived_java_mirror_raw(oop m) {
assert(DumpSharedSpaces, "called only during runtime");
_archived_mirror = CompressedOops::encode(m);
}
#endif // INCLUDE_CDS_JAVA_HEAP
Klass* Klass::array_klass_or_null(int rank) {
EXCEPTION_MARK;
// No exception can be thrown by array_klass_impl when called with or_null == true.
// (In anycase, the execption mark will fail if it do so)
return array_klass_impl(true, rank, THREAD);
}
Klass* Klass::array_klass_or_null() {
EXCEPTION_MARK;
// No exception can be thrown by array_klass_impl when called with or_null == true.
// (In anycase, the execption mark will fail if it do so)
return array_klass_impl(true, THREAD);
}
Klass* Klass::array_klass_impl(bool or_null, int rank, TRAPS) {
fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
return NULL;
}
Klass* Klass::array_klass_impl(bool or_null, TRAPS) {
fatal("array_klass should be dispatched to InstanceKlass, ObjArrayKlass or TypeArrayKlass");
return NULL;
}
oop Klass::class_loader() const { return class_loader_data()->class_loader(); }
// In product mode, this function doesn't have virtual function calls so
// there might be some performance advantage to handling InstanceKlass here.
const char* Klass::external_name() const {
if (is_instance_klass()) {
const InstanceKlass* ik = static_cast<const InstanceKlass*>(this);
if (ik->is_anonymous()) {
char addr_buf[20];
jio_snprintf(addr_buf, 20, "/" INTPTR_FORMAT, p2i(ik));
size_t addr_len = strlen(addr_buf);
size_t name_len = name()->utf8_length();
char* result = NEW_RESOURCE_ARRAY(char, name_len + addr_len + 1);
name()->as_klass_external_name(result, (int) name_len + 1);
assert(strlen(result) == name_len, "");
strcpy(result + name_len, addr_buf);
assert(strlen(result) == name_len + addr_len, "");
return result;
}
}
if (name() == NULL) return "<unknown>";
return name()->as_klass_external_name();
}
const char* Klass::signature_name() const {
if (name() == NULL) return "<unknown>";
return name()->as_C_string();
}
const char* Klass::external_kind() const {
if (is_interface()) return "interface";
if (is_abstract()) return "abstract class";
return "class";
}
// Unless overridden, modifier_flags is 0.
jint Klass::compute_modifier_flags(TRAPS) const {
return 0;
}
int Klass::atomic_incr_biased_lock_revocation_count() {
return (int) Atomic::add(1, &_biased_lock_revocation_count);
}
// Unless overridden, jvmti_class_status has no flags set.
jint Klass::jvmti_class_status() const {
return 0;
}
// Printing
void Klass::print_on(outputStream* st) const {
ResourceMark rm;
// print title
st->print("%s", internal_name());
print_address_on(st);
st->cr();
}
void Klass::oop_print_on(oop obj, outputStream* st) {
ResourceMark rm;
// print title
st->print_cr("%s ", internal_name());
obj->print_address_on(st);
if (WizardMode) {
// print header
obj->mark()->print_on(st);
}
// print class
st->print(" - klass: ");
obj->klass()->print_value_on(st);
st->cr();
}
void Klass::oop_print_value_on(oop obj, outputStream* st) {
// print title
ResourceMark rm; // Cannot print in debug mode without this
st->print("%s", internal_name());
obj->print_address_on(st);
}
#if INCLUDE_SERVICES
// Size Statistics
void Klass::collect_statistics(KlassSizeStats *sz) const {
sz->_klass_bytes = sz->count(this);
sz->_mirror_bytes = sz->count(java_mirror_no_keepalive());
sz->_secondary_supers_bytes = sz->count_array(secondary_supers());
sz->_ro_bytes += sz->_secondary_supers_bytes;
sz->_rw_bytes += sz->_klass_bytes + sz->_mirror_bytes;
}
#endif // INCLUDE_SERVICES
// Verification
void Klass::verify_on(outputStream* st) {
// This can be expensive, but it is worth checking that this klass is actually
// in the CLD graph but not in production.
assert(Metaspace::contains((address)this), "Should be");
guarantee(this->is_klass(),"should be klass");
if (super() != NULL) {
guarantee(super()->is_klass(), "should be klass");
}
if (secondary_super_cache() != NULL) {
Klass* ko = secondary_super_cache();
guarantee(ko->is_klass(), "should be klass");
}
for ( uint i = 0; i < primary_super_limit(); i++ ) {
Klass* ko = _primary_supers[i];
if (ko != NULL) {
guarantee(ko->is_klass(), "should be klass");
}
}
if (java_mirror_no_keepalive() != NULL) {
guarantee(oopDesc::is_oop(java_mirror_no_keepalive()), "should be instance");
}
}
void Klass::oop_verify_on(oop obj, outputStream* st) {
guarantee(oopDesc::is_oop(obj), "should be oop");
guarantee(obj->klass()->is_klass(), "klass field is not a klass");
}
Klass* Klass::decode_klass_raw(narrowKlass narrow_klass) {
return (Klass*)(void*)( (uintptr_t)Universe::narrow_klass_base() +
((uintptr_t)narrow_klass << Universe::narrow_klass_shift()));
}
bool Klass::is_valid(Klass* k) {
if (!is_aligned(k, sizeof(MetaWord))) return false;
if ((size_t)k < os::min_page_size()) return false;
if (!os::is_readable_range(k, k + 1)) return false;
if (!MetaspaceUtils::is_range_in_committed(k, k + 1)) return false;
if (!Symbol::is_valid(k->name())) return false;
return ClassLoaderDataGraph::is_valid(k->class_loader_data());
}
klassVtable Klass::vtable() const {
return klassVtable(const_cast<Klass*>(this), start_of_vtable(), vtable_length() / vtableEntry::size());
}
vtableEntry* Klass::start_of_vtable() const {
return (vtableEntry*) ((address)this + in_bytes(vtable_start_offset()));
}
Method* Klass::method_at_vtable(int index) {
#ifndef PRODUCT
assert(index >= 0, "valid vtable index");
if (DebugVtables) {
verify_vtable_index(index);
}
#endif
return start_of_vtable()[index].method();
}
ByteSize Klass::vtable_start_offset() {
return in_ByteSize(InstanceKlass::header_size() * wordSize);
}
#ifndef PRODUCT
bool Klass::verify_vtable_index(int i) {
int limit = vtable_length()/vtableEntry::size();
assert(i >= 0 && i < limit, "index %d out of bounds %d", i, limit);
return true;
}
bool Klass::verify_itable_index(int i) {
assert(is_instance_klass(), "");
int method_count = klassItable::method_count_for_interface(this);
assert(i >= 0 && i < method_count, "index out of bounds");
return true;
}
#endif // PRODUCT
// Caller needs ResourceMark
// joint_in_module_of_loader provides an optimization if 2 classes are in
// the same module to succinctly print out relevant information about their
// module name and class loader's name_and_id for error messages.
// Format:
// <fully-qualified-external-class-name1> and <fully-qualified-external-class-name2>
// are in module <module-name>[@<version>]
// of loader <loader-name_and_id>[, parent loader <parent-loader-name_and_id>]
const char* Klass::joint_in_module_of_loader(const Klass* class2, bool include_parent_loader) const {
assert(module() == class2->module(), "classes do not have the same module");
const char* class1_name = external_name();
size_t len = strlen(class1_name) + 1;
const char* class2_description = class2->class_in_module_of_loader(true, include_parent_loader);
len += strlen(class2_description);
len += strlen(" and ");
char* joint_description = NEW_RESOURCE_ARRAY_RETURN_NULL(char, len);
// Just return the FQN if error when allocating string
if (joint_description == NULL) {
return class1_name;
}
jio_snprintf(joint_description, len, "%s and %s",
class1_name,
class2_description);
return joint_description;
}
// Caller needs ResourceMark
// class_in_module_of_loader provides a standard way to include
// relevant information about a class, such as its module name as
// well as its class loader's name_and_id, in error messages and logging.
// Format:
// <fully-qualified-external-class-name> is in module <module-name>[@<version>]
// of loader <loader-name_and_id>[, parent loader <parent-loader-name_and_id>]
const char* Klass::class_in_module_of_loader(bool use_are, bool include_parent_loader) const {
// 1. fully qualified external name of class
const char* klass_name = external_name();
size_t len = strlen(klass_name) + 1;
// 2. module name + @version
const char* module_name = "";
const char* version = "";
bool has_version = false;
bool module_is_named = false;
const char* module_name_phrase = "";
const Klass* bottom_klass = is_objArray_klass() ?
ObjArrayKlass::cast(this)->bottom_klass() : this;
if (bottom_klass->is_instance_klass()) {
ModuleEntry* module = InstanceKlass::cast(bottom_klass)->module();
if (module->is_named()) {
module_is_named = true;
module_name_phrase = "module ";
module_name = module->name()->as_C_string();
len += strlen(module_name);
// Use version if exists and is not a jdk module
if (module->should_show_version()) {
has_version = true;
version = module->version()->as_C_string();
// Include stlen(version) + 1 for the "@"
len += strlen(version) + 1;
}
} else {
module_name = UNNAMED_MODULE;
len += UNNAMED_MODULE_LEN;
}
} else {
// klass is an array of primitives, module is java.base
module_is_named = true;
module_name_phrase = "module ";
module_name = JAVA_BASE_NAME;
len += JAVA_BASE_NAME_LEN;
}
// 3. class loader's name_and_id
ClassLoaderData* cld = class_loader_data();
assert(cld != NULL, "class_loader_data should not be null");
const char* loader_name_and_id = cld->loader_name_and_id();
len += strlen(loader_name_and_id);
// 4. include parent loader information
const char* parent_loader_phrase = "";
const char* parent_loader_name_and_id = "";
if (include_parent_loader &&
!cld->is_builtin_class_loader_data()) {
oop parent_loader = java_lang_ClassLoader::parent(class_loader());
ClassLoaderData *parent_cld = ClassLoaderData::class_loader_data_or_null(parent_loader);
// The parent loader's ClassLoaderData could be null if it is
// a delegating class loader that has never defined a class.
// In this case the loader's name must be obtained via the parent loader's oop.
if (parent_cld == NULL) {
oop cl_name_and_id = java_lang_ClassLoader::nameAndId(parent_loader);
if (cl_name_and_id != NULL) {
parent_loader_name_and_id = java_lang_String::as_utf8_string(cl_name_and_id);
}
} else {
parent_loader_name_and_id = parent_cld->loader_name_and_id();
}
parent_loader_phrase = ", parent loader ";
len += strlen(parent_loader_phrase) + strlen(parent_loader_name_and_id);
}
// Start to construct final full class description string
len += ((use_are) ? strlen(" are in ") : strlen(" is in "));
len += strlen(module_name_phrase) + strlen(" of loader ");
char* class_description = NEW_RESOURCE_ARRAY_RETURN_NULL(char, len);
// Just return the FQN if error when allocating string
if (class_description == NULL) {
return klass_name;
}
jio_snprintf(class_description, len, "%s %s in %s%s%s%s of loader %s%s%s",
klass_name,
(use_are) ? "are" : "is",
module_name_phrase,
module_name,
(has_version) ? "@" : "",
(has_version) ? version : "",
loader_name_and_id,
parent_loader_phrase,
parent_loader_name_and_id);
return class_description;
}