/* * 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. *
*/
//------------------------------------------------------------------------------------------------------------------------ // Implementation of CallInfo
void CallInfo::set_interface(Klass* resolved_klass, const methodHandle& resolved_method, const methodHandle& selected_method, int itable_index, TRAPS) { // This is only called for interface methods. If the resolved_method // comes from java/lang/Object, it can be the subject of a virtual call, so // we should pick the vtable index from the resolved method. // In that case, the caller must call set_virtual instead of set_interface.
assert(resolved_method->method_holder()->is_interface(), "");
assert(itable_index == resolved_method()->itable_index(), "");
set_common(resolved_klass, resolved_method, selected_method, CallInfo::itable_call, itable_index, CHECK);
}
// utility query for unreflecting a method
CallInfo::CallInfo(Method* resolved_method, Klass* resolved_klass, TRAPS) {
Klass* resolved_method_holder = resolved_method->method_holder(); if (resolved_klass == NULL) { // 2nd argument defaults to holder of 1st
resolved_klass = resolved_method_holder;
}
_resolved_klass = resolved_klass;
_resolved_method = methodHandle(THREAD, resolved_method);
_selected_method = methodHandle(THREAD, resolved_method); // classify:
CallKind kind = CallInfo::unknown_kind; int index = resolved_method->vtable_index(); if (resolved_method->can_be_statically_bound()) {
kind = CallInfo::direct_call;
} elseif (!resolved_method_holder->is_interface()) { // Could be an Object method inherited into an interface, but still a vtable call.
kind = CallInfo::vtable_call;
} elseif (!resolved_klass->is_interface()) { // A default or miranda method. Compute the vtable index.
index = LinkResolver::vtable_index_of_interface_method(resolved_klass, _resolved_method);
assert(index >= 0 , "we should have valid vtable index at this point");
kind = CallInfo::vtable_call;
} elseif (resolved_method->has_vtable_index()) { // Can occur if an interface redeclares a method of Object.
#ifdef ASSERT // Ensure that this is really the case.
Klass* object_klass = vmClasses::Object_klass();
Method * object_resolved_method = object_klass->vtable().method_at(index);
assert(object_resolved_method->name() == resolved_method->name(), "Object and interface method names should match at vtable index %d, %s != %s",
index, object_resolved_method->name()->as_C_string(), resolved_method->name()->as_C_string());
assert(object_resolved_method->signature() == resolved_method->signature(), "Object and interface method signatures should match at vtable index %d, %s != %s",
index, object_resolved_method->signature()->as_C_string(), resolved_method->signature()->as_C_string()); #endif// ASSERT
kind = CallInfo::vtable_call;
} else { // A regular interface call.
kind = CallInfo::itable_call;
index = resolved_method->itable_index();
}
assert(index == Method::nonvirtual_vtable_index || index >= 0, "bad index %d", index);
_call_kind = kind;
_call_index = index;
_resolved_appendix = Handle(); // Find or create a ResolvedMethod instance for this Method*
set_resolved_method_name(CHECK);
#ifdef ASSERT void CallInfo::verify() { switch (call_kind()) { // the meaning and allowed value of index depends on kind case CallInfo::direct_call: if (_call_index == Method::nonvirtual_vtable_index) break; // else fall through to check vtable index: case CallInfo::vtable_call:
assert(resolved_klass()->verify_vtable_index(_call_index), ""); break; case CallInfo::itable_call:
assert(resolved_method()->method_holder()->verify_itable_index(_call_index), ""); break; case CallInfo::unknown_kind:
assert(call_kind() != CallInfo::unknown_kind, "CallInfo must be set"); break; default:
fatal("Unexpected call kind %d", call_kind());
}
} #endif// ASSERT
//------------------------------------------------------------------------------------------------------------------------ // Implementation of LinkInfo
LinkInfo::LinkInfo(const constantPoolHandle& pool, int index, const methodHandle& current_method, TRAPS) { // resolve klass
_resolved_klass = pool->klass_ref_at(index, CHECK);
// Get name, signature, and static klass
_name = pool->name_ref_at(index);
_signature = pool->signature_ref_at(index);
_tag = pool->tag_ref_at(index);
_current_klass = pool->pool_holder();
_current_method = current_method;
// Coming from the constant pool always checks access
_check_access = true;
_check_loader_constraints = true;
}
LinkInfo::LinkInfo(const constantPoolHandle& pool, int index, TRAPS) { // resolve klass
_resolved_klass = pool->klass_ref_at(index, CHECK);
// Get name, signature, and static klass
_name = pool->name_ref_at(index);
_signature = pool->signature_ref_at(index);
_tag = pool->tag_ref_at(index);
_current_klass = pool->pool_holder();
_current_method = methodHandle();
// Coming from the constant pool always checks access
_check_access = true;
_check_loader_constraints = true;
}
} #endif// PRODUCT //------------------------------------------------------------------------------------------------------------------------ // Klass resolution
void LinkResolver::check_klass_accessibility(Klass* ref_klass, Klass* sel_klass, TRAPS) {
Klass* base_klass = sel_klass; if (sel_klass->is_objArray_klass()) {
base_klass = ObjArrayKlass::cast(sel_klass)->bottom_klass();
} // The element type could be a typeArray - we only need the access // check if it is a reference to another class. if (!base_klass->is_instance_klass()) { return; // no relevant check to do
}
Reflection::VerifyClassAccessResults vca_result =
Reflection::verify_class_access(ref_klass, InstanceKlass::cast(base_klass), true); if (vca_result != Reflection::ACCESS_OK) {
ResourceMark rm(THREAD); char* msg = Reflection::verify_class_access_msg(ref_klass,
InstanceKlass::cast(base_klass),
vca_result); bool same_module = (base_klass->module() == ref_klass->module()); if (msg == NULL) {
Exceptions::fthrow(
THREAD_AND_LOCATION,
vmSymbols::java_lang_IllegalAccessError(), "failed to access class %s from class %s (%s%s%s)",
base_klass->external_name(),
ref_klass->external_name(),
(same_module) ? base_klass->joint_in_module_of_loader(ref_klass) : base_klass->class_in_module_of_loader(),
(same_module) ? "" : "; ",
(same_module) ? "" : ref_klass->class_in_module_of_loader());
} else { // Use module specific message returned by verify_class_access_msg().
Exceptions::fthrow(
THREAD_AND_LOCATION,
vmSymbols::java_lang_IllegalAccessError(), "%s", msg);
}
}
}
//------------------------------------------------------------------------------------------------------------------------ // Method resolution // // According to JVM spec. $5.4.3c & $5.4.3d
// Look up method in klasses, including static methods // Then look up local default methods
Method* LinkResolver::lookup_method_in_klasses(const LinkInfo& link_info, bool checkpolymorphism, bool in_imethod_resolve) {
NoSafepointVerifier nsv; // Method* returned may not be reclaimed
Klass* klass = link_info.resolved_klass();
Symbol* name = link_info.name();
Symbol* signature = link_info.signature();
// Ignore overpasses so statics can be found during resolution
Method* result = klass->uncached_lookup_method(name, signature, Klass::OverpassLookupMode::skip);
if (klass->is_array_klass()) { // Only consider klass and super klass for arrays return result;
}
InstanceKlass* ik = InstanceKlass::cast(klass);
// JDK 8, JVMS 5.4.3.4: Interface method resolution should // ignore static and non-public methods of java.lang.Object, // like clone and finalize. if (in_imethod_resolve &&
result != NULL &&
ik->is_interface() &&
(result->is_static() || !result->is_public()) &&
result->method_holder() == vmClasses::Object_klass()) {
result = NULL;
}
// Before considering default methods, check for an overpass in the // current class if a method has not been found. if (result == NULL) {
result = ik->find_method(name, signature);
}
if (result == NULL) {
Array<Method*>* default_methods = ik->default_methods(); if (default_methods != NULL) {
result = InstanceKlass::find_method(default_methods, name, signature);
}
}
if (checkpolymorphism && result != NULL) {
vmIntrinsics::ID iid = result->intrinsic_id(); if (MethodHandles::is_signature_polymorphic(iid)) { // Do not link directly to these. The VM must produce a synthetic one using lookup_polymorphic_method. return NULL;
}
} return result;
}
// returns first instance method // Looks up method in classes, then looks up local default methods
Method* LinkResolver::lookup_instance_method_in_klasses(Klass* klass,
Symbol* name,
Symbol* signature,
Klass::PrivateLookupMode private_mode) {
Method* result = klass->uncached_lookup_method(name, signature, Klass::OverpassLookupMode::find, private_mode);
// Specify 'true' in order to skip default methods when searching the // interfaces. Function lookup_method_in_klasses() already looked for // the method in the default methods table. return ik->lookup_method_in_all_interfaces(cp_info.name(), cp_info.signature(), Klass::DefaultsLookupMode::skip);
}
vmIntrinsics::ID iid = MethodHandles::signature_polymorphic_name_id(name);
log_info(methodhandles)("lookup_polymorphic_method iid=%s %s.%s%s",
vmIntrinsics::name_at(iid), klass->external_name(),
name->as_C_string(), full_signature->as_C_string()); if ((klass == vmClasses::MethodHandle_klass() ||
klass == vmClasses::VarHandle_klass()) &&
iid != vmIntrinsics::_none) { if (MethodHandles::is_signature_polymorphic_intrinsic(iid)) { // Most of these do not need an up-call to Java to resolve, so can be done anywhere. // Do not erase last argument type (MemberName) if it is a static linkTo method. bool keep_last_arg = MethodHandles::is_signature_polymorphic_static(iid);
TempNewSymbol basic_signature =
MethodHandles::lookup_basic_type_signature(full_signature, keep_last_arg);
log_info(methodhandles)("lookup_polymorphic_method %s %s => basic %s",
name->as_C_string(),
full_signature->as_C_string(),
basic_signature->as_C_string());
Method* result = SystemDictionary::find_method_handle_intrinsic(iid,
basic_signature,
CHECK_NULL); if (result != NULL) {
assert(result->is_method_handle_intrinsic(), "MH.invokeBasic or MH.linkTo* intrinsic");
assert(result->intrinsic_id() != vmIntrinsics::_invokeGeneric, "wrong place to find this");
assert(basic_signature == result->signature(), "predict the result signature"); if (lt_mh.is_enabled()) {
LogStream ls(lt_mh);
ls.print("lookup_polymorphic_method => intrinsic ");
result->print_on(&ls);
}
} return result;
} elseif (iid == vmIntrinsics::_invokeGeneric
&& THREAD->can_call_java()
&& appendix_result_or_null != NULL) { // This is a method with type-checking semantics. // We will ask Java code to spin an adapter method for it. if (!MethodHandles::enabled()) { // Make sure the Java part of the runtime has been booted up.
Klass* natives = vmClasses::MethodHandleNatives_klass(); if (natives == NULL || InstanceKlass::cast(natives)->is_not_initialized()) {
SystemDictionary::resolve_or_fail(vmSymbols::java_lang_invoke_MethodHandleNatives(),
Handle(),
Handle(), true,
CHECK_NULL);
}
}
// Special case: arrays always override "clone". JVMS 2.15. // If the resolved klass is an array class, and the declaring class // is java.lang.Object and the method is "clone", set the flags // to public. // // We'll check for the method name first, as that's most likely // to be false (so we'll short-circuit out of these tests). if (sel_method->name() == vmSymbols::clone_name() &&
sel_klass == vmClasses::Object_klass() &&
resolved_klass->is_array_klass()) { // We need to change "protected" to "public".
assert(flags.is_protected(), "clone not protected?");
jint new_flags = flags.as_int();
new_flags = new_flags & (~JVM_ACC_PROTECTED);
new_flags = new_flags | JVM_ACC_PUBLIC;
flags.set_flags(new_flags);
} // assert(extra_arg_result_or_null != NULL, "must be able to return extra argument");
bool can_access = Reflection::verify_member_access(ref_klass,
resolved_klass,
sel_klass,
flags, true, false, CHECK); // Any existing exceptions that may have been thrown // have been allowed to propagate. if (!can_access) {
ResourceMark rm(THREAD);
stringStream ss; bool same_module = (sel_klass->module() == ref_klass->module());
ss.print("class %s tried to access %s%s%smethod '%s' (%s%s%s)",
ref_klass->external_name(),
sel_method->is_abstract() ? "abstract " : "",
sel_method->is_protected() ? "protected " : "",
sel_method->is_private() ? "private " : "",
sel_method->external_name(),
(same_module) ? ref_klass->joint_in_module_of_loader(sel_klass) : ref_klass->class_in_module_of_loader(),
(same_module) ? "" : "; ",
(same_module) ? "" : sel_klass->class_in_module_of_loader()
);
// For private access see if there was a problem with nest host // resolution, and if so report that as part of the message. if (sel_method->is_private()) {
print_nest_host_error_on(&ss, ref_klass, sel_klass);
}
Method* LinkResolver::resolve_method_statically(Bytecodes::Code code, const constantPoolHandle& pool, int index, TRAPS) { // This method is used only // (1) in C2 from InlineTree::ok_to_inline (via ciMethod::check_call), // and // (2) in Bytecode_invoke::static_target // It appears to fail when applied to an invokeinterface call site. // FIXME: Remove this method and ciMethod::check_call; refactor to use the other LinkResolver entry points. // resolve klass if (code == Bytecodes::_invokedynamic) {
Klass* resolved_klass = vmClasses::MethodHandle_klass();
Symbol* method_name = vmSymbols::invoke_name();
Symbol* method_signature = pool->signature_ref_at(index);
Klass* current_klass = pool->pool_holder();
LinkInfo link_info(resolved_klass, method_name, method_signature, current_klass); return resolve_method(link_info, code, THREAD);
}
// Check and print a loader constraint violation message for method or interface method void LinkResolver::check_method_loader_constraints(const LinkInfo& link_info, const methodHandle& resolved_method, constchar* method_type, TRAPS) {
Handle current_loader(THREAD, link_info.current_klass()->class_loader());
Handle resolved_loader(THREAD, resolved_method->method_holder()->class_loader());
ResourceMark rm(THREAD);
Symbol* failed_type_symbol =
SystemDictionary::check_signature_loaders(link_info.signature(), /*klass_being_linked*/ NULL, // We are not linking class
current_loader,
resolved_loader, true); if (failed_type_symbol != NULL) {
Klass* current_class = link_info.current_klass();
ClassLoaderData* current_loader_data = current_class->class_loader_data();
assert(current_loader_data != NULL, "current class has no class loader data");
Klass* resolved_method_class = resolved_method->method_holder();
ClassLoaderData* target_loader_data = resolved_method_class->class_loader_data();
assert(target_loader_data != NULL, "resolved method's class has no class loader data");
stringStream ss;
ss.print("loader constraint violation: when resolving %s '", method_type);
Method::print_external_name(&ss, link_info.resolved_klass(), link_info.name(), link_info.signature());
ss.print("' the class loader %s of the current class, %s," " and the class loader %s for the method's defining class, %s, have" " different Class objects for the type %s used in the signature (%s; %s)",
current_loader_data->loader_name_and_id(),
current_class->name()->as_C_string(),
target_loader_data->loader_name_and_id(),
resolved_method_class->name()->as_C_string(),
failed_type_symbol->as_C_string(),
current_class->class_in_module_of_loader(false, true),
resolved_method_class->class_in_module_of_loader(false, true));
THROW_MSG(vmSymbols::java_lang_LinkageError(), ss.as_string());
}
}
ResourceMark rm(THREAD); // needed for check_signature_loaders
Symbol* failed_type_symbol =
SystemDictionary::check_signature_loaders(sig, /*klass_being_linked*/ NULL, // We are not linking class
ref_loader, sel_loader, false); if (failed_type_symbol != NULL) {
stringStream ss; constchar* failed_type_name = failed_type_symbol->as_klass_external_name();
ss.print("loader constraint violation: when resolving field \"%s\" of type %s, " "the class loader %s of the current class, %s, " "and the class loader %s for the field's defining %s, %s, " "have different Class objects for type %s (%s; %s)",
field->as_C_string(),
failed_type_name,
current_klass->class_loader_data()->loader_name_and_id(),
current_klass->external_name(),
sel_klass->class_loader_data()->loader_name_and_id(),
sel_klass->external_kind(),
sel_klass->external_name(),
failed_type_name,
current_klass->class_in_module_of_loader(false, true),
sel_klass->class_in_module_of_loader(false, true));
THROW_MSG(vmSymbols::java_lang_LinkageError(), ss.as_string());
}
}
// 1. For invokevirtual, cannot call an interface method if (code == Bytecodes::_invokevirtual && resolved_klass->is_interface()) {
ResourceMark rm(THREAD); char buf[200];
jio_snprintf(buf, sizeof(buf), "Found interface %s, but class was expected",
resolved_klass->external_name());
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
}
// 2. check constant pool tag for called method - must be JVM_CONSTANT_Methodref if (!link_info.tag().is_invalid() && !link_info.tag().is_method()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Method '");
Method::print_external_name(&ss, link_info.resolved_klass(), link_info.name(), link_info.signature());
ss.print("' must be Methodref constant");
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
// 3. lookup method in resolved klass and its super klasses
methodHandle resolved_method(THREAD, lookup_method_in_klasses(link_info, true, false));
// 4. lookup method in all the interfaces implemented by the resolved klass if (resolved_method.is_null() && !resolved_klass->is_array_klass()) { // not found in the class hierarchy
resolved_method = methodHandle(THREAD, lookup_method_in_interfaces(link_info));
if (resolved_method.is_null()) { // JSR 292: see if this is an implicitly generated method MethodHandle.linkToVirtual(*...), etc
Method* method = lookup_polymorphic_method(link_info, (Handle*)NULL, THREAD);
resolved_method = methodHandle(THREAD, method); if (HAS_PENDING_EXCEPTION) {
nested_exception = Handle(THREAD, PENDING_EXCEPTION);
CLEAR_PENDING_EXCEPTION;
}
}
}
// 6. access checks, access checking may be turned off when calling from within the VM.
Klass* current_klass = link_info.current_klass(); if (link_info.check_access()) {
assert(current_klass != NULL , "current_klass should not be null");
// check if method can be accessed by the referring class
check_method_accessability(current_klass,
resolved_klass,
resolved_method->method_holder(),
resolved_method,
CHECK_NULL);
} if (link_info.check_loader_constraints()) { // check loader constraints
check_method_loader_constraints(link_info, resolved_method, "method", CHECK_NULL);
}
// Do linktime resolution of a method in the interface within the context of the specified bytecode.
Method* LinkResolver::resolve_interface_method(const LinkInfo& link_info, Bytecodes::Code code, TRAPS) {
// check if klass is interface if (!resolved_klass->is_interface()) {
ResourceMark rm(THREAD); char buf[200];
jio_snprintf(buf, sizeof(buf), "Found class %s, but interface was expected", resolved_klass->external_name());
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
}
// check constant pool tag for called method - must be JVM_CONSTANT_InterfaceMethodref if (!link_info.tag().is_invalid() && !link_info.tag().is_interface_method()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Method '");
Method::print_external_name(&ss, link_info.resolved_klass(), link_info.name(), link_info.signature());
ss.print("' must be InterfaceMethodref constant");
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
// lookup method in this interface or its super, java.lang.Object // JDK8: also look for static methods
methodHandle resolved_method(THREAD, lookup_method_in_klasses(link_info, false, true));
if (resolved_method.is_null() && !resolved_klass->is_array_klass()) { // lookup method in all the super-interfaces
resolved_method = methodHandle(THREAD, lookup_method_in_interfaces(link_info));
}
if (resolved_method.is_null()) { // no method found
ResourceMark rm(THREAD);
stringStream ss;
ss.print("'");
Method::print_external_name(&ss, resolved_klass, link_info.name(), link_info.signature());
ss.print("'");
THROW_MSG_NULL(vmSymbols::java_lang_NoSuchMethodError(), ss.as_string());
}
if (link_info.check_access()) { // JDK8 adds non-public interface methods, and accessability check requirement
Klass* current_klass = link_info.current_klass();
assert(current_klass != NULL , "current_klass should not be null");
// check if method can be accessed by the referring class
check_method_accessability(current_klass,
resolved_klass,
resolved_method->method_holder(),
resolved_method,
CHECK_NULL);
} if (link_info.check_loader_constraints()) {
check_method_loader_constraints(link_info, resolved_method, "interface method", CHECK_NULL);
}
//------------------------------------------------------------------------------------------------------------------------ // Field resolution
void LinkResolver::check_field_accessability(Klass* ref_klass,
Klass* resolved_klass,
Klass* sel_klass, const fieldDescriptor& fd,
TRAPS) { bool can_access = Reflection::verify_member_access(ref_klass,
resolved_klass,
sel_klass,
fd.access_flags(), true, false, CHECK); // Any existing exceptions that may have been thrown, for example LinkageErrors // from nest-host resolution, have been allowed to propagate. if (!can_access) { bool same_module = (sel_klass->module() == ref_klass->module());
ResourceMark rm(THREAD);
stringStream ss;
ss.print("class %s tried to access %s%sfield %s.%s (%s%s%s)",
ref_klass->external_name(),
fd.is_protected() ? "protected " : "",
fd.is_private() ? "private " : "",
sel_klass->external_name(),
fd.name()->as_C_string(),
(same_module) ? ref_klass->joint_in_module_of_loader(sel_klass) : ref_klass->class_in_module_of_loader(),
(same_module) ? "" : "; ",
(same_module) ? "" : sel_klass->class_in_module_of_loader()
); // For private access see if there was a problem with nest host // resolution, and if so report that as part of the message. if (fd.is_private()) {
print_nest_host_error_on(&ss, ref_klass, sel_klass);
}
Exceptions::fthrow(THREAD_AND_LOCATION,
vmSymbols::java_lang_IllegalAccessError(), "%s",
ss.as_string()
); return;
}
}
bool is_static = (byte == Bytecodes::_getstatic || byte == Bytecodes::_putstatic); bool is_put = (byte == Bytecodes::_putfield || byte == Bytecodes::_putstatic || byte == Bytecodes::_nofast_putfield); // Check if there's a resolved klass containing the field
Klass* resolved_klass = link_info.resolved_klass();
Symbol* field = link_info.name();
Symbol* sig = link_info.signature();
if (resolved_klass == NULL) {
ResourceMark rm(THREAD);
THROW_MSG(vmSymbols::java_lang_NoSuchFieldError(), field->as_C_string());
}
// Resolve instance field
Klass* sel_klass = resolved_klass->find_field(field, sig, &fd); // check if field exists; i.e., if a klass containing the field def has been selected if (sel_klass == NULL) {
ResourceMark rm(THREAD);
THROW_MSG(vmSymbols::java_lang_NoSuchFieldError(), field->as_C_string());
}
// Access checking may be turned off when calling from within the VM.
Klass* current_klass = link_info.current_klass(); if (link_info.check_access()) {
// check for errors if (is_static != fd.is_static()) {
ResourceMark rm(THREAD); char msg[200];
jio_snprintf(msg, sizeof(msg), "Expected %s field %s.%s", is_static ? "static" : "non-static", resolved_klass->external_name(), fd.name()->as_C_string());
THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), msg);
}
// A final field can be modified only // (1) by methods declared in the class declaring the field and // (2) by the <clinit> method (in case of a static field) // or by the <init> method (in case of an instance field). if (is_put && fd.access_flags().is_final()) {
if (sel_klass != current_klass) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Update to %s final field %s.%s attempted from a different class (%s) than the field's declaring class",
is_static ? "static" : "non-static", resolved_klass->external_name(), fd.name()->as_C_string(),
current_klass->external_name());
THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), ss.as_string());
}
if (fd.constants()->pool_holder()->major_version() >= 53) {
Method* m = link_info.current_method();
assert(m != NULL, "information about the current method must be available for 'put' bytecodes"); bool is_initialized_static_final_update = (byte == Bytecodes::_putstatic &&
fd.is_static() &&
!m->is_static_initializer()); bool is_initialized_instance_final_update = ((byte == Bytecodes::_putfield || byte == Bytecodes::_nofast_putfield) &&
!fd.is_static() &&
!m->is_object_initializer());
if (is_initialized_static_final_update || is_initialized_instance_final_update) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Update to %s final field %s.%s attempted from a different method (%s) than the initializer method %s ",
is_static ? "static" : "non-static", resolved_klass->external_name(), fd.name()->as_C_string(),
m->name()->as_C_string(),
is_static ? "" : "");
THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), ss.as_string());
}
}
}
// initialize resolved_klass if necessary // note 1: the klass which declared the field must be initialized (i.e, sel_klass) // according to the newest JVM spec (5.5, p.170) - was bug (gri 7/28/99) // // note 2: we don't want to force initialization if we are just checking // if the field access is legal; e.g., during compilation if (is_static && initialize_class) {
sel_klass->initialize(CHECK);
}
}
// return information. note that the klass is set to the actual klass containing the // field, otherwise access of static fields in superclasses will not work.
}
//------------------------------------------------------------------------------------------------------------------------ // Invoke resolution // // Naming conventions: // // resolved_method the specified method (i.e., static receiver specified via constant pool index) // sel_method the selected method (selected via run-time lookup; e.g., based on dynamic receiver class) // resolved_klass the specified klass (i.e., specified via constant pool index) // recv_klass the receiver klass
// The resolved class can change as a result of this resolution.
Klass* resolved_klass = resolved_method->method_holder();
// Initialize klass (this should only happen if everything is ok) if (initialize_class && resolved_klass->should_be_initialized()) {
resolved_klass->initialize(CHECK); // Use updated LinkInfo to reresolve with resolved method holder
LinkInfo new_info(resolved_klass, link_info.name(), link_info.signature(),
link_info.current_klass(),
link_info.check_access() ? LinkInfo::AccessCheck::required : LinkInfo::AccessCheck::skip,
link_info.check_loader_constraints() ? LinkInfo::LoaderConstraintCheck::required : LinkInfo::LoaderConstraintCheck::skip);
resolved_method = linktime_resolve_static_method(new_info, CHECK);
}
if (resolved_method->is_continuation_native_intrinsic()
&& resolved_method->from_interpreted_entry() == NULL) { // does a load_acquire
methodHandle mh(THREAD, resolved_method); // Generate a compiled form of the enterSpecial intrinsic.
AdapterHandlerLibrary::create_native_wrapper(mh);
}
// setup result
result.set_static(resolved_klass, methodHandle(THREAD, resolved_method), CHECK);
JFR_ONLY(Jfr::on_resolution(result, CHECK);)
}
// Invokespecial is called for multiple special reasons: // <init> // local private method invocation, for classes and interfaces // superclass.method, which can also resolve to a default method // and the selected method is recalculated relative to the direct superclass // superinterface.method, which explicitly does not check shadowing
Klass* resolved_klass = link_info.resolved_klass();
Method* resolved_method = NULL;
// check if method name is <init>, that it is found in same klass as static type if (resolved_method->name() == vmSymbols::object_initializer_name() &&
resolved_method->method_holder() != resolved_klass) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("%s: method '", resolved_klass->external_name());
resolved_method->signature()->print_as_signature_external_return_type(&ss);
ss.print(" %s(", resolved_method->name()->as_C_string());
resolved_method->signature()->print_as_signature_external_parameters(&ss);
ss.print(")' not found");
Exceptions::fthrow(
THREAD_AND_LOCATION,
vmSymbols::java_lang_NoSuchMethodError(), "%s", ss.as_string()); return NULL;
}
// ensure that invokespecial's interface method reference is in // a direct superinterface, not an indirect superinterface
Klass* current_klass = link_info.current_klass(); if (current_klass != NULL && resolved_klass->is_interface()) {
InstanceKlass* klass_to_check = InstanceKlass::cast(current_klass); // Disable verification for the dynamically-generated reflection bytecodes. bool is_reflect = klass_to_check->is_subclass_of(
vmClasses::reflect_MagicAccessorImpl_klass());
if (!is_reflect &&
!klass_to_check->is_same_or_direct_interface(resolved_klass)) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Interface method reference: '");
resolved_method->print_external_name(&ss);
ss.print("', is in an indirect superinterface of %s",
current_klass->external_name());
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
}
// check if not static if (resolved_method->is_static()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Expecting non-static method '");
resolved_method->print_external_name(&ss);
ss.print("'");
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
// resolved method is selected method unless we have an old-style lookup // for a superclass method // Invokespecial for a superinterface, resolved method is selected method, // no checks for shadowing
methodHandle sel_method(THREAD, resolved_method());
if (link_info.check_access() && // check if the method is not <init>
resolved_method->name() != vmSymbols::object_initializer_name()) {
Klass* current_klass = link_info.current_klass();
// Check if the class of the resolved_klass is a superclass // (not supertype in order to exclude interface classes) of the current class. // This check is not performed for super.invoke for interface methods // in super interfaces. if (current_klass->is_subclass_of(resolved_klass) &&
current_klass != resolved_klass) { // Lookup super method
Klass* super_klass = current_klass->super();
Method* instance_method = lookup_instance_method_in_klasses(super_klass,
resolved_method->name(),
resolved_method->signature(),
Klass::PrivateLookupMode::find);
sel_method = methodHandle(THREAD, instance_method);
// check if found if (sel_method.is_null()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("'");
resolved_method->print_external_name(&ss);
ss.print("'");
THROW_MSG(vmSymbols::java_lang_AbstractMethodError(), ss.as_string()); // check loader constraints if found a different method
} elseif (link_info.check_loader_constraints() && sel_method() != resolved_method()) {
check_method_loader_constraints(link_info, sel_method, "method", CHECK);
}
}
// Check that the class of objectref (the receiver) is the current class or interface, // or a subtype of the current class or interface (the sender), otherwise invokespecial // throws IllegalAccessError. // The verifier checks that the sender is a subtype of the class in the I/MR operand. // The verifier also checks that the receiver is a subtype of the sender, if the sender is // a class. If the sender is an interface, the check has to be performed at runtime.
InstanceKlass* sender = InstanceKlass::cast(current_klass); if (sender->is_interface() && recv.not_null()) {
Klass* receiver_klass = recv->klass(); if (!receiver_klass->is_subtype_of(sender)) {
ResourceMark rm(THREAD); char buf[500];
jio_snprintf(buf, sizeof(buf), "Receiver class %s must be the current class or a subtype of interface %s",
receiver_klass->external_name(),
sender->external_name());
THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), buf);
}
}
}
// check if not static if (sel_method->is_static()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Expecting non-static method '");
resolved_method->print_external_name(&ss);
ss.print("'");
THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
// check if abstract if (sel_method->is_abstract()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("'");
Method::print_external_name(&ss, resolved_klass, sel_method->name(), sel_method->signature());
ss.print("'");
THROW_MSG(vmSymbols::java_lang_AbstractMethodError(), ss.as_string());
}
assert(resolved_method->name() != vmSymbols::object_initializer_name(), "should have been checked in verifier");
assert(resolved_method->name() != vmSymbols::class_initializer_name (), "should have been checked in verifier");
// runtime method resolution if (check_null_and_abstract && recv.is_null()) { // check if receiver exists THROW(vmSymbols::java_lang_NullPointerException());
}
// Virtual methods cannot be resolved before its klass has been linked, for otherwise the Method*'s // has not been rewritten, and the vtable initialized. Make sure to do this after the nullcheck, since // a missing receiver might result in a bogus lookup.
assert(resolved_method->method_holder()->is_linked(), "must be linked");
// do lookup based on receiver klass using the vtable index if (resolved_method->method_holder()->is_interface()) { // default or miranda method
vtable_index = vtable_index_of_interface_method(resolved_klass, resolved_method);
assert(vtable_index >= 0 , "we should have valid vtable index at this point");
selected_method = methodHandle(THREAD, recv_klass->method_at_vtable(vtable_index));
} else { // at this point we are sure that resolved_method is virtual and not // a default or miranda method; therefore, it must have a valid vtable index.
assert(!resolved_method->has_itable_index(), "");
vtable_index = resolved_method->vtable_index(); // We could get a negative vtable_index of nonvirtual_vtable_index for private // methods, or for final methods. Private methods never appear in the vtable // and never override other methods. As an optimization, final methods are // never put in the vtable, unless they override an existing method. // So if we do get nonvirtual_vtable_index, it means the selected method is the // resolved method, and it can never be changed by an override. if (vtable_index == Method::nonvirtual_vtable_index) {
assert(resolved_method->can_be_statically_bound(), "cannot override this method");
selected_method = resolved_method;
} else {
selected_method = methodHandle(THREAD, recv_klass->method_at_vtable(vtable_index));
}
}
// check if method exists if (selected_method.is_null()) {
throw_abstract_method_error(resolved_method, recv_klass, CHECK);
}
// check if abstract if (check_null_and_abstract && selected_method->is_abstract()) { // Pass arguments for generating a verbose error message.
throw_abstract_method_error(resolved_method, selected_method, recv_klass, CHECK);
}
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