| /* |
| * 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. |
| * |
| */ |
| |
| #ifndef SHARE_VM_OOPS_KLASS_HPP |
| #define SHARE_VM_OOPS_KLASS_HPP |
| |
| #include "classfile/classLoaderData.hpp" |
| #include "memory/iterator.hpp" |
| #include "memory/memRegion.hpp" |
| #include "oops/metadata.hpp" |
| #include "oops/oop.hpp" |
| #include "oops/oopHandle.hpp" |
| #include "utilities/accessFlags.hpp" |
| #include "utilities/macros.hpp" |
| #if INCLUDE_JFR |
| #include "jfr/support/jfrTraceIdExtension.hpp" |
| #endif |
| |
| // Klass IDs for all subclasses of Klass |
| enum KlassID { |
| InstanceKlassID, |
| InstanceRefKlassID, |
| InstanceMirrorKlassID, |
| InstanceClassLoaderKlassID, |
| TypeArrayKlassID, |
| ObjArrayKlassID |
| }; |
| |
| const uint KLASS_ID_COUNT = 6; |
| |
| // |
| // A Klass provides: |
| // 1: language level class object (method dictionary etc.) |
| // 2: provide vm dispatch behavior for the object |
| // Both functions are combined into one C++ class. |
| |
| // One reason for the oop/klass dichotomy in the implementation is |
| // that we don't want a C++ vtbl pointer in every object. Thus, |
| // normal oops don't have any virtual functions. Instead, they |
| // forward all "virtual" functions to their klass, which does have |
| // a vtbl and does the C++ dispatch depending on the object's |
| // actual type. (See oop.inline.hpp for some of the forwarding code.) |
| // ALL FUNCTIONS IMPLEMENTING THIS DISPATCH ARE PREFIXED WITH "oop_"! |
| |
| // Forward declarations. |
| template <class T> class Array; |
| template <class T> class GrowableArray; |
| class fieldDescriptor; |
| class KlassSizeStats; |
| class klassVtable; |
| class ModuleEntry; |
| class PackageEntry; |
| class ParCompactionManager; |
| class PSPromotionManager; |
| class vtableEntry; |
| |
| class Klass : public Metadata { |
| friend class VMStructs; |
| friend class JVMCIVMStructs; |
| protected: |
| // If you add a new field that points to any metaspace object, you |
| // must add this field to Klass::metaspace_pointers_do(). |
| |
| // note: put frequently-used fields together at start of klass structure |
| // for better cache behavior (may not make much of a difference but sure won't hurt) |
| enum { _primary_super_limit = 8 }; |
| |
| // The "layout helper" is a combined descriptor of object layout. |
| // For klasses which are neither instance nor array, the value is zero. |
| // |
| // For instances, layout helper is a positive number, the instance size. |
| // This size is already passed through align_object_size and scaled to bytes. |
| // The low order bit is set if instances of this class cannot be |
| // allocated using the fastpath. |
| // |
| // For arrays, layout helper is a negative number, containing four |
| // distinct bytes, as follows: |
| // MSB:[tag, hsz, ebt, log2(esz)]:LSB |
| // where: |
| // tag is 0x80 if the elements are oops, 0xC0 if non-oops |
| // hsz is array header size in bytes (i.e., offset of first element) |
| // ebt is the BasicType of the elements |
| // esz is the element size in bytes |
| // This packed word is arranged so as to be quickly unpacked by the |
| // various fast paths that use the various subfields. |
| // |
| // The esz bits can be used directly by a SLL instruction, without masking. |
| // |
| // Note that the array-kind tag looks like 0x00 for instance klasses, |
| // since their length in bytes is always less than 24Mb. |
| // |
| // Final note: This comes first, immediately after C++ vtable, |
| // because it is frequently queried. |
| jint _layout_helper; |
| |
| // Klass identifier used to implement devirtualized oop closure dispatching. |
| const KlassID _id; |
| |
| // The fields _super_check_offset, _secondary_super_cache, _secondary_supers |
| // and _primary_supers all help make fast subtype checks. See big discussion |
| // in doc/server_compiler/checktype.txt |
| // |
| // Where to look to observe a supertype (it is &_secondary_super_cache for |
| // secondary supers, else is &_primary_supers[depth()]. |
| juint _super_check_offset; |
| |
| // Class name. Instance classes: java/lang/String, etc. Array classes: [I, |
| // [Ljava/lang/String;, etc. Set to zero for all other kinds of classes. |
| Symbol* _name; |
| |
| // Cache of last observed secondary supertype |
| Klass* _secondary_super_cache; |
| // Array of all secondary supertypes |
| Array<Klass*>* _secondary_supers; |
| // Ordered list of all primary supertypes |
| Klass* _primary_supers[_primary_super_limit]; |
| // java/lang/Class instance mirroring this class |
| OopHandle _java_mirror; |
| // Superclass |
| Klass* _super; |
| // First subclass (NULL if none); _subklass->next_sibling() is next one |
| Klass* _subklass; |
| // Sibling link (or NULL); links all subklasses of a klass |
| Klass* _next_sibling; |
| |
| // All klasses loaded by a class loader are chained through these links |
| Klass* _next_link; |
| |
| // The VM's representation of the ClassLoader used to load this class. |
| // Provide access the corresponding instance java.lang.ClassLoader. |
| ClassLoaderData* _class_loader_data; |
| |
| jint _modifier_flags; // Processed access flags, for use by Class.getModifiers. |
| AccessFlags _access_flags; // Access flags. The class/interface distinction is stored here. |
| |
| JFR_ONLY(DEFINE_TRACE_ID_FIELD;) |
| |
| // Biased locking implementation and statistics |
| // (the 64-bit chunk goes first, to avoid some fragmentation) |
| jlong _last_biased_lock_bulk_revocation_time; |
| markOop _prototype_header; // Used when biased locking is both enabled and disabled for this type |
| jint _biased_lock_revocation_count; |
| |
| // vtable length |
| int _vtable_len; |
| |
| private: |
| // This is an index into FileMapHeader::_shared_path_table[], to |
| // associate this class with the JAR file where it's loaded from during |
| // dump time. If a class is not loaded from the shared archive, this field is |
| // -1. |
| jshort _shared_class_path_index; |
| |
| #if INCLUDE_CDS |
| // Flags of the current shared class. |
| u2 _shared_class_flags; |
| enum { |
| _has_raw_archived_mirror = 1, |
| _has_signer_and_not_archived = 1 << 2 |
| }; |
| #endif |
| // The _archived_mirror is set at CDS dump time pointing to the cached mirror |
| // in the open archive heap region when archiving java object is supported. |
| CDS_JAVA_HEAP_ONLY(narrowOop _archived_mirror;) |
| |
| protected: |
| |
| // Constructor |
| Klass(KlassID id); |
| Klass() : _id(KlassID(-1)) { assert(DumpSharedSpaces || UseSharedSpaces, "only for cds"); } |
| |
| void* operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw(); |
| |
| public: |
| int id() { return _id; } |
| |
| enum DefaultsLookupMode { find_defaults, skip_defaults }; |
| enum OverpassLookupMode { find_overpass, skip_overpass }; |
| enum StaticLookupMode { find_static, skip_static }; |
| enum PrivateLookupMode { find_private, skip_private }; |
| |
| bool is_klass() const volatile { return true; } |
| |
| // super() cannot be InstanceKlass* -- Java arrays are covariant, and _super is used |
| // to implement that. NB: the _super of "[Ljava/lang/Integer;" is "[Ljava/lang/Number;" |
| // If this is not what your code expects, you're probably looking for Klass::java_super(). |
| Klass* super() const { return _super; } |
| void set_super(Klass* k) { _super = k; } |
| |
| // initializes _super link, _primary_supers & _secondary_supers arrays |
| void initialize_supers(Klass* k, Array<InstanceKlass*>* transitive_interfaces, TRAPS); |
| |
| // klass-specific helper for initializing _secondary_supers |
| virtual GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots, |
| Array<InstanceKlass*>* transitive_interfaces); |
| |
| // java_super is the Java-level super type as specified by Class.getSuperClass. |
| virtual InstanceKlass* java_super() const { return NULL; } |
| |
| juint super_check_offset() const { return _super_check_offset; } |
| void set_super_check_offset(juint o) { _super_check_offset = o; } |
| |
| Klass* secondary_super_cache() const { return _secondary_super_cache; } |
| void set_secondary_super_cache(Klass* k) { _secondary_super_cache = k; } |
| |
| Array<Klass*>* secondary_supers() const { return _secondary_supers; } |
| void set_secondary_supers(Array<Klass*>* k) { _secondary_supers = k; } |
| |
| // Return the element of the _super chain of the given depth. |
| // If there is no such element, return either NULL or this. |
| Klass* primary_super_of_depth(juint i) const { |
| assert(i < primary_super_limit(), "oob"); |
| Klass* super = _primary_supers[i]; |
| assert(super == NULL || super->super_depth() == i, "correct display"); |
| return super; |
| } |
| |
| // Can this klass be a primary super? False for interfaces and arrays of |
| // interfaces. False also for arrays or classes with long super chains. |
| bool can_be_primary_super() const { |
| const juint secondary_offset = in_bytes(secondary_super_cache_offset()); |
| return super_check_offset() != secondary_offset; |
| } |
| virtual bool can_be_primary_super_slow() const; |
| |
| // Returns number of primary supers; may be a number in the inclusive range [0, primary_super_limit]. |
| juint super_depth() const { |
| if (!can_be_primary_super()) { |
| return primary_super_limit(); |
| } else { |
| juint d = (super_check_offset() - in_bytes(primary_supers_offset())) / sizeof(Klass*); |
| assert(d < primary_super_limit(), "oob"); |
| assert(_primary_supers[d] == this, "proper init"); |
| return d; |
| } |
| } |
| |
| // java mirror |
| oop java_mirror() const; |
| void set_java_mirror(Handle m); |
| |
| oop archived_java_mirror_raw() NOT_CDS_JAVA_HEAP_RETURN_(NULL); // no GC barrier |
| void set_archived_java_mirror_raw(oop m) NOT_CDS_JAVA_HEAP_RETURN; // no GC barrier |
| |
| // Temporary mirror switch used by RedefineClasses |
| // Both mirrors are on the ClassLoaderData::_handles list already so no |
| // barriers are needed. |
| void set_java_mirror_handle(OopHandle mirror) { _java_mirror = mirror; } |
| OopHandle java_mirror_handle() const { |
| return _java_mirror; |
| } |
| |
| // modifier flags |
| jint modifier_flags() const { return _modifier_flags; } |
| void set_modifier_flags(jint flags) { _modifier_flags = flags; } |
| |
| // size helper |
| int layout_helper() const { return _layout_helper; } |
| void set_layout_helper(int lh) { _layout_helper = lh; } |
| |
| // Note: for instances layout_helper() may include padding. |
| // Use InstanceKlass::contains_field_offset to classify field offsets. |
| |
| // sub/superklass links |
| Klass* subklass() const { return _subklass; } |
| Klass* next_sibling() const { return _next_sibling; } |
| InstanceKlass* superklass() const; |
| void append_to_sibling_list(); // add newly created receiver to superklass' subklass list |
| |
| void set_next_link(Klass* k) { _next_link = k; } |
| Klass* next_link() const { return _next_link; } // The next klass defined by the class loader. |
| |
| // class loader data |
| ClassLoaderData* class_loader_data() const { return _class_loader_data; } |
| void set_class_loader_data(ClassLoaderData* loader_data) { _class_loader_data = loader_data; } |
| |
| int shared_classpath_index() const { |
| return _shared_class_path_index; |
| }; |
| |
| void set_shared_classpath_index(int index) { |
| _shared_class_path_index = index; |
| }; |
| |
| void set_has_raw_archived_mirror() { |
| CDS_ONLY(_shared_class_flags |= _has_raw_archived_mirror;) |
| } |
| void clear_has_raw_archived_mirror() { |
| CDS_ONLY(_shared_class_flags &= ~_has_raw_archived_mirror;) |
| } |
| bool has_raw_archived_mirror() const { |
| CDS_ONLY(return (_shared_class_flags & _has_raw_archived_mirror) != 0;) |
| NOT_CDS(return false;) |
| } |
| #if INCLUDE_CDS |
| void set_has_signer_and_not_archived() { |
| _shared_class_flags |= _has_signer_and_not_archived; |
| } |
| bool has_signer_and_not_archived() const { |
| assert(DumpSharedSpaces, "dump time only"); |
| return (_shared_class_flags & _has_signer_and_not_archived) != 0; |
| } |
| #endif // INCLUDE_CDS |
| |
| // Obtain the module or package for this class |
| virtual ModuleEntry* module() const = 0; |
| virtual PackageEntry* package() const = 0; |
| |
| protected: // internal accessors |
| void set_subklass(Klass* s); |
| void set_next_sibling(Klass* s); |
| |
| public: |
| |
| // Compiler support |
| static ByteSize super_offset() { return in_ByteSize(offset_of(Klass, _super)); } |
| static ByteSize super_check_offset_offset() { return in_ByteSize(offset_of(Klass, _super_check_offset)); } |
| static ByteSize primary_supers_offset() { return in_ByteSize(offset_of(Klass, _primary_supers)); } |
| static ByteSize secondary_super_cache_offset() { return in_ByteSize(offset_of(Klass, _secondary_super_cache)); } |
| static ByteSize secondary_supers_offset() { return in_ByteSize(offset_of(Klass, _secondary_supers)); } |
| static ByteSize java_mirror_offset() { return in_ByteSize(offset_of(Klass, _java_mirror)); } |
| static ByteSize modifier_flags_offset() { return in_ByteSize(offset_of(Klass, _modifier_flags)); } |
| static ByteSize layout_helper_offset() { return in_ByteSize(offset_of(Klass, _layout_helper)); } |
| static ByteSize access_flags_offset() { return in_ByteSize(offset_of(Klass, _access_flags)); } |
| |
| // Unpacking layout_helper: |
| enum { |
| _lh_neutral_value = 0, // neutral non-array non-instance value |
| _lh_instance_slow_path_bit = 0x01, |
| _lh_log2_element_size_shift = BitsPerByte*0, |
| _lh_log2_element_size_mask = BitsPerLong-1, |
| _lh_element_type_shift = BitsPerByte*1, |
| _lh_element_type_mask = right_n_bits(BitsPerByte), // shifted mask |
| _lh_header_size_shift = BitsPerByte*2, |
| _lh_header_size_mask = right_n_bits(BitsPerByte), // shifted mask |
| _lh_array_tag_bits = 2, |
| _lh_array_tag_shift = BitsPerInt - _lh_array_tag_bits, |
| _lh_array_tag_obj_value = ~0x01 // 0x80000000 >> 30 |
| }; |
| |
| static const unsigned int _lh_array_tag_type_value = 0Xffffffff; // ~0x00, // 0xC0000000 >> 30 |
| |
| static int layout_helper_size_in_bytes(jint lh) { |
| assert(lh > (jint)_lh_neutral_value, "must be instance"); |
| return (int) lh & ~_lh_instance_slow_path_bit; |
| } |
| static bool layout_helper_needs_slow_path(jint lh) { |
| assert(lh > (jint)_lh_neutral_value, "must be instance"); |
| return (lh & _lh_instance_slow_path_bit) != 0; |
| } |
| static bool layout_helper_is_instance(jint lh) { |
| return (jint)lh > (jint)_lh_neutral_value; |
| } |
| static bool layout_helper_is_array(jint lh) { |
| return (jint)lh < (jint)_lh_neutral_value; |
| } |
| static bool layout_helper_is_typeArray(jint lh) { |
| // _lh_array_tag_type_value == (lh >> _lh_array_tag_shift); |
| return (juint)lh >= (juint)(_lh_array_tag_type_value << _lh_array_tag_shift); |
| } |
| static bool layout_helper_is_objArray(jint lh) { |
| // _lh_array_tag_obj_value == (lh >> _lh_array_tag_shift); |
| return (jint)lh < (jint)(_lh_array_tag_type_value << _lh_array_tag_shift); |
| } |
| static int layout_helper_header_size(jint lh) { |
| assert(lh < (jint)_lh_neutral_value, "must be array"); |
| int hsize = (lh >> _lh_header_size_shift) & _lh_header_size_mask; |
| assert(hsize > 0 && hsize < (int)sizeof(oopDesc)*3, "sanity"); |
| return hsize; |
| } |
| static BasicType layout_helper_element_type(jint lh) { |
| assert(lh < (jint)_lh_neutral_value, "must be array"); |
| int btvalue = (lh >> _lh_element_type_shift) & _lh_element_type_mask; |
| assert(btvalue >= T_BOOLEAN && btvalue <= T_OBJECT, "sanity"); |
| return (BasicType) btvalue; |
| } |
| |
| // Want a pattern to quickly diff against layout header in register |
| // find something less clever! |
| static int layout_helper_boolean_diffbit() { |
| jint zlh = array_layout_helper(T_BOOLEAN); |
| jint blh = array_layout_helper(T_BYTE); |
| assert(zlh != blh, "array layout helpers must differ"); |
| int diffbit = 1; |
| while ((diffbit & (zlh ^ blh)) == 0 && (diffbit & zlh) == 0) { |
| diffbit <<= 1; |
| assert(diffbit != 0, "make sure T_BOOLEAN has a different bit than T_BYTE"); |
| } |
| return diffbit; |
| } |
| |
| static int layout_helper_log2_element_size(jint lh) { |
| assert(lh < (jint)_lh_neutral_value, "must be array"); |
| int l2esz = (lh >> _lh_log2_element_size_shift) & _lh_log2_element_size_mask; |
| assert(l2esz <= LogBytesPerLong, |
| "sanity. l2esz: 0x%x for lh: 0x%x", (uint)l2esz, (uint)lh); |
| return l2esz; |
| } |
| static jint array_layout_helper(jint tag, int hsize, BasicType etype, int log2_esize) { |
| return (tag << _lh_array_tag_shift) |
| | (hsize << _lh_header_size_shift) |
| | ((int)etype << _lh_element_type_shift) |
| | (log2_esize << _lh_log2_element_size_shift); |
| } |
| static jint instance_layout_helper(jint size, bool slow_path_flag) { |
| return (size << LogBytesPerWord) |
| | (slow_path_flag ? _lh_instance_slow_path_bit : 0); |
| } |
| static int layout_helper_to_size_helper(jint lh) { |
| assert(lh > (jint)_lh_neutral_value, "must be instance"); |
| // Note that the following expression discards _lh_instance_slow_path_bit. |
| return lh >> LogBytesPerWord; |
| } |
| // Out-of-line version computes everything based on the etype: |
| static jint array_layout_helper(BasicType etype); |
| |
| // What is the maximum number of primary superclasses any klass can have? |
| #ifdef PRODUCT |
| static juint primary_super_limit() { return _primary_super_limit; } |
| #else |
| static juint primary_super_limit() { |
| assert(FastSuperclassLimit <= _primary_super_limit, "parameter oob"); |
| return FastSuperclassLimit; |
| } |
| #endif |
| |
| // vtables |
| klassVtable vtable() const; |
| int vtable_length() const { return _vtable_len; } |
| |
| // subclass check |
| bool is_subclass_of(const Klass* k) const; |
| // subtype check: true if is_subclass_of, or if k is interface and receiver implements it |
| bool is_subtype_of(Klass* k) const { |
| juint off = k->super_check_offset(); |
| Klass* sup = *(Klass**)( (address)this + off ); |
| const juint secondary_offset = in_bytes(secondary_super_cache_offset()); |
| if (sup == k) { |
| return true; |
| } else if (off != secondary_offset) { |
| return false; |
| } else { |
| return search_secondary_supers(k); |
| } |
| } |
| |
| bool search_secondary_supers(Klass* k) const; |
| |
| // Find LCA in class hierarchy |
| Klass *LCA( Klass *k ); |
| |
| // Check whether reflection/jni/jvm code is allowed to instantiate this class; |
| // if not, throw either an Error or an Exception. |
| virtual void check_valid_for_instantiation(bool throwError, TRAPS); |
| |
| // array copying |
| virtual void copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS); |
| |
| // tells if the class should be initialized |
| virtual bool should_be_initialized() const { return false; } |
| // initializes the klass |
| virtual void initialize(TRAPS); |
| // lookup operation for MethodLookupCache |
| friend class MethodLookupCache; |
| virtual Klass* find_field(Symbol* name, Symbol* signature, fieldDescriptor* fd) const; |
| virtual Method* uncached_lookup_method(const Symbol* name, const Symbol* signature, |
| OverpassLookupMode overpass_mode, |
| PrivateLookupMode = find_private) const; |
| public: |
| Method* lookup_method(const Symbol* name, const Symbol* signature) const { |
| return uncached_lookup_method(name, signature, find_overpass); |
| } |
| |
| // array class with specific rank |
| Klass* array_klass(int rank, TRAPS) { return array_klass_impl(false, rank, THREAD); } |
| |
| // array class with this klass as element type |
| Klass* array_klass(TRAPS) { return array_klass_impl(false, THREAD); } |
| |
| // These will return NULL instead of allocating on the heap: |
| // NB: these can block for a mutex, like other functions with TRAPS arg. |
| Klass* array_klass_or_null(int rank); |
| Klass* array_klass_or_null(); |
| |
| virtual oop protection_domain() const = 0; |
| |
| oop class_loader() const; |
| |
| virtual oop klass_holder() const { return class_loader(); } |
| |
| protected: |
| virtual Klass* array_klass_impl(bool or_null, int rank, TRAPS); |
| virtual Klass* array_klass_impl(bool or_null, TRAPS); |
| |
| void set_vtable_length(int len) { _vtable_len= len; } |
| |
| vtableEntry* start_of_vtable() const; |
| public: |
| Method* method_at_vtable(int index); |
| |
| static ByteSize vtable_start_offset(); |
| static ByteSize vtable_length_offset() { |
| return byte_offset_of(Klass, _vtable_len); |
| } |
| |
| // CDS support - remove and restore oops from metadata. Oops are not shared. |
| virtual void remove_unshareable_info(); |
| virtual void remove_java_mirror(); |
| virtual void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS); |
| |
| protected: |
| // computes the subtype relationship |
| virtual bool compute_is_subtype_of(Klass* k); |
| public: |
| // subclass accessor (here for convenience; undefined for non-klass objects) |
| virtual bool is_leaf_class() const { fatal("not a class"); return false; } |
| public: |
| // ALL FUNCTIONS BELOW THIS POINT ARE DISPATCHED FROM AN OOP |
| // These functions describe behavior for the oop not the KLASS. |
| |
| // actual oop size of obj in memory |
| virtual int oop_size(oop obj) const = 0; |
| |
| // Size of klass in word size. |
| virtual int size() const = 0; |
| #if INCLUDE_SERVICES |
| virtual void collect_statistics(KlassSizeStats *sz) const; |
| #endif |
| |
| // Returns the Java name for a class (Resource allocated) |
| // For arrays, this returns the name of the element with a leading '['. |
| // For classes, this returns the name with the package separators |
| // turned into '.'s. |
| const char* external_name() const; |
| // Returns the name for a class (Resource allocated) as the class |
| // would appear in a signature. |
| // For arrays, this returns the name of the element with a leading '['. |
| // For classes, this returns the name with a leading 'L' and a trailing ';' |
| // and the package separators as '/'. |
| virtual const char* signature_name() const; |
| |
| const char* joint_in_module_of_loader(const Klass* class2, bool include_parent_loader = false) const; |
| const char* class_in_module_of_loader(bool use_are = false, bool include_parent_loader = false) const; |
| |
| // Returns "interface", "abstract class" or "class". |
| const char* external_kind() const; |
| |
| // type testing operations |
| #ifdef ASSERT |
| protected: |
| virtual bool is_instance_klass_slow() const { return false; } |
| virtual bool is_array_klass_slow() const { return false; } |
| virtual bool is_objArray_klass_slow() const { return false; } |
| virtual bool is_typeArray_klass_slow() const { return false; } |
| #endif // ASSERT |
| public: |
| |
| // Fast non-virtual versions |
| #ifndef ASSERT |
| #define assert_same_query(xval, xcheck) xval |
| #else |
| private: |
| static bool assert_same_query(bool xval, bool xslow) { |
| assert(xval == xslow, "slow and fast queries agree"); |
| return xval; |
| } |
| public: |
| #endif |
| inline bool is_instance_klass() const { return assert_same_query( |
| layout_helper_is_instance(layout_helper()), |
| is_instance_klass_slow()); } |
| inline bool is_array_klass() const { return assert_same_query( |
| layout_helper_is_array(layout_helper()), |
| is_array_klass_slow()); } |
| inline bool is_objArray_klass() const { return assert_same_query( |
| layout_helper_is_objArray(layout_helper()), |
| is_objArray_klass_slow()); } |
| inline bool is_typeArray_klass() const { return assert_same_query( |
| layout_helper_is_typeArray(layout_helper()), |
| is_typeArray_klass_slow()); } |
| #undef assert_same_query |
| |
| // Access flags |
| AccessFlags access_flags() const { return _access_flags; } |
| void set_access_flags(AccessFlags flags) { _access_flags = flags; } |
| |
| bool is_public() const { return _access_flags.is_public(); } |
| bool is_final() const { return _access_flags.is_final(); } |
| bool is_interface() const { return _access_flags.is_interface(); } |
| bool is_abstract() const { return _access_flags.is_abstract(); } |
| bool is_super() const { return _access_flags.is_super(); } |
| bool is_synthetic() const { return _access_flags.is_synthetic(); } |
| void set_is_synthetic() { _access_flags.set_is_synthetic(); } |
| bool has_finalizer() const { return _access_flags.has_finalizer(); } |
| bool has_final_method() const { return _access_flags.has_final_method(); } |
| void set_has_finalizer() { _access_flags.set_has_finalizer(); } |
| void set_has_final_method() { _access_flags.set_has_final_method(); } |
| bool has_vanilla_constructor() const { return _access_flags.has_vanilla_constructor(); } |
| void set_has_vanilla_constructor() { _access_flags.set_has_vanilla_constructor(); } |
| bool has_miranda_methods () const { return access_flags().has_miranda_methods(); } |
| void set_has_miranda_methods() { _access_flags.set_has_miranda_methods(); } |
| bool is_shared() const { return access_flags().is_shared_class(); } // shadows MetaspaceObj::is_shared)() |
| void set_is_shared() { _access_flags.set_is_shared_class(); } |
| |
| bool is_cloneable() const; |
| void set_is_cloneable(); |
| |
| // Biased locking support |
| // Note: the prototype header is always set up to be at least the |
| // prototype markOop. If biased locking is enabled it may further be |
| // biasable and have an epoch. |
| markOop prototype_header() const { return _prototype_header; } |
| // NOTE: once instances of this klass are floating around in the |
| // system, this header must only be updated at a safepoint. |
| // NOTE 2: currently we only ever set the prototype header to the |
| // biasable prototype for instanceKlasses. There is no technical |
| // reason why it could not be done for arrayKlasses aside from |
| // wanting to reduce the initial scope of this optimization. There |
| // are potential problems in setting the bias pattern for |
| // JVM-internal oops. |
| inline void set_prototype_header(markOop header); |
| static ByteSize prototype_header_offset() { return in_ByteSize(offset_of(Klass, _prototype_header)); } |
| |
| int biased_lock_revocation_count() const { return (int) _biased_lock_revocation_count; } |
| // Atomically increments biased_lock_revocation_count and returns updated value |
| int atomic_incr_biased_lock_revocation_count(); |
| void set_biased_lock_revocation_count(int val) { _biased_lock_revocation_count = (jint) val; } |
| jlong last_biased_lock_bulk_revocation_time() { return _last_biased_lock_bulk_revocation_time; } |
| void set_last_biased_lock_bulk_revocation_time(jlong cur_time) { _last_biased_lock_bulk_revocation_time = cur_time; } |
| |
| JFR_ONLY(DEFINE_TRACE_ID_METHODS;) |
| |
| virtual void metaspace_pointers_do(MetaspaceClosure* iter); |
| virtual MetaspaceObj::Type type() const { return ClassType; } |
| |
| // Iff the class loader (or mirror for unsafe anonymous classes) is alive the |
| // Klass is considered alive. Has already been marked as unloading. |
| bool is_loader_alive() const { return !class_loader_data()->is_unloading(); } |
| |
| // Load the klass's holder as a phantom. This is useful when a weak Klass |
| // pointer has been "peeked" and then must be kept alive before it may |
| // be used safely. |
| oop holder_phantom() const; |
| |
| static void clean_weak_klass_links(bool unloading_occurred, bool clean_alive_klasses = true); |
| static void clean_subklass_tree() { |
| clean_weak_klass_links(/*unloading_occurred*/ true , /* clean_alive_klasses */ false); |
| } |
| |
| // GC specific object visitors |
| // |
| #if INCLUDE_PARALLELGC |
| // Parallel Scavenge |
| virtual void oop_ps_push_contents( oop obj, PSPromotionManager* pm) = 0; |
| // Parallel Compact |
| virtual void oop_pc_follow_contents(oop obj, ParCompactionManager* cm) = 0; |
| virtual void oop_pc_update_pointers(oop obj, ParCompactionManager* cm) = 0; |
| #endif |
| |
| virtual void array_klasses_do(void f(Klass* k)) {} |
| |
| // Return self, except for abstract classes with exactly 1 |
| // implementor. Then return the 1 concrete implementation. |
| Klass *up_cast_abstract(); |
| |
| // klass name |
| Symbol* name() const { return _name; } |
| void set_name(Symbol* n); |
| |
| public: |
| // jvm support |
| virtual jint compute_modifier_flags(TRAPS) const; |
| |
| // JVMTI support |
| virtual jint jvmti_class_status() const; |
| |
| // Printing |
| virtual void print_on(outputStream* st) const; |
| |
| virtual void oop_print_value_on(oop obj, outputStream* st); |
| virtual void oop_print_on (oop obj, outputStream* st); |
| |
| virtual const char* internal_name() const = 0; |
| |
| // Verification |
| virtual void verify_on(outputStream* st); |
| void verify() { verify_on(tty); } |
| |
| #ifndef PRODUCT |
| bool verify_vtable_index(int index); |
| #endif |
| |
| virtual void oop_verify_on(oop obj, outputStream* st); |
| |
| static bool is_null(narrowKlass obj); |
| static bool is_null(Klass* obj); |
| |
| // klass encoding for klass pointer in objects. |
| static narrowKlass encode_klass_not_null(Klass* v); |
| static narrowKlass encode_klass(Klass* v); |
| |
| static Klass* decode_klass_not_null(narrowKlass v); |
| static Klass* decode_klass(narrowKlass v); |
| }; |
| |
| #endif // SHARE_VM_OOPS_KLASS_HPP |