1 /*
   2  * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_OOPS_INSTANCEKLASS_HPP
  26 #define SHARE_OOPS_INSTANCEKLASS_HPP
  27 
  28 #include "code/vmreg.hpp"
  29 #include "memory/allocation.hpp"
  30 #include "memory/referenceType.hpp"
  31 #include "oops/annotations.hpp"
  32 #include "oops/constMethod.hpp"
  33 #include "oops/fieldInfo.hpp"
  34 #include "oops/instanceKlassFlags.hpp"
  35 #include "oops/instanceOop.hpp"
  36 #include "oops/refArrayKlass.hpp"
  37 #include "runtime/handles.hpp"
  38 #include "runtime/javaThread.hpp"
  39 #include "utilities/accessFlags.hpp"
  40 #include "utilities/align.hpp"
  41 #include "utilities/growableArray.hpp"
  42 #include "utilities/macros.hpp"
  43 #if INCLUDE_JFR
  44 #include "jfr/support/jfrKlassExtension.hpp"
  45 #endif
  46 
  47 class ConstantPool;
  48 class DeoptimizationScope;
  49 class klassItable;
  50 class RecordComponent;
  51 
  52 // An InstanceKlass is the VM level representation of a Java class.
  53 // It contains all information needed for at class at execution runtime.
  54 
  55 //  InstanceKlass embedded field layout (after declared fields):
  56 //    [EMBEDDED Java vtable             ] size in words = vtable_len
  57 //    [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
  58 //      The embedded nonstatic oop-map blocks are short pairs (offset, length)
  59 //      indicating where oops are located in instances of this klass.
  60 //    [EMBEDDED implementor of the interface] only exist for interface
  61 //    [EMBEDDED InlineKlass::Members] only if is an InlineKlass instance
  62 
  63 
  64 // forward declaration for class -- see below for definition
  65 #if INCLUDE_JVMTI
  66 class BreakpointInfo;
  67 #endif
  68 class ClassFileParser;
  69 class ClassFileStream;
  70 class KlassDepChange;
  71 class DependencyContext;
  72 class fieldDescriptor;
  73 class JNIid;
  74 class JvmtiCachedClassFieldMap;
  75 class nmethodBucket;
  76 class OopMapCache;
  77 class BufferedInlineTypeBlob;
  78 class InterpreterOopMap;
  79 class PackageEntry;
  80 class ModuleEntry;
  81 
  82 // This is used in iterators below.
  83 class FieldClosure: public StackObj {
  84 public:
  85   virtual void do_field(fieldDescriptor* fd) = 0;
  86 };
  87 
  88 // Print fields.
  89 // If "obj" argument to constructor is null, prints static fields, otherwise prints non-static fields.
  90 class FieldPrinter: public FieldClosure {
  91    oop _obj;
  92    outputStream* _st;
  93    int _indent;
  94    int _base_offset;
  95  public:
  96    FieldPrinter(outputStream* st, oop obj = nullptr, int indent = 0, int base_offset = 0) :
  97                  _obj(obj), _st(st), _indent(indent), _base_offset(base_offset) {}
  98    void do_field(fieldDescriptor* fd);
  99 };
 100 
 101 // Describes where oops are located in instances of this klass.
 102 class OopMapBlock {
 103  public:
 104   // Byte offset of the first oop mapped by this block.
 105   int offset() const          { return _offset; }
 106   void set_offset(int offset) { _offset = offset; }
 107 
 108   // Number of oops in this block.
 109   uint count() const         { return _count; }
 110   void set_count(uint count) { _count = count; }
 111 
 112   void increment_count(int diff) { _count += diff; }
 113 
 114   int offset_span() const { return _count * heapOopSize; }
 115 
 116   int end_offset() const {
 117     return offset() + offset_span();
 118   }
 119 
 120   bool is_contiguous(int another_offset) const {
 121     return another_offset == end_offset();
 122   }
 123 
 124   // sizeof(OopMapBlock) in words.
 125   static int size_in_words() {
 126     return align_up((int)sizeof(OopMapBlock), wordSize) >>
 127       LogBytesPerWord;
 128   }
 129 
 130   static int compare_offset(const OopMapBlock* a, const OopMapBlock* b) {
 131     return a->offset() - b->offset();
 132   }
 133 
 134  private:
 135   int  _offset;
 136   uint _count;
 137 };
 138 
 139 struct JvmtiCachedClassFileData;
 140 
 141 class InlineLayoutInfo : public MetaspaceObj {
 142   InlineKlass* _klass;
 143   LayoutKind _kind;
 144   int _null_marker_offset; // null marker offset for this field, relative to the beginning of the current container
 145 
 146  public:
 147   InlineLayoutInfo(): _klass(nullptr), _kind(LayoutKind::UNKNOWN), _null_marker_offset(-1)  {}
 148   InlineLayoutInfo(InlineKlass* ik, LayoutKind kind, int size, int nm_offset):
 149     _klass(ik), _kind(kind), _null_marker_offset(nm_offset) {}
 150 
 151   InlineKlass* klass() const { return _klass; }
 152   void set_klass(InlineKlass* k) { _klass = k; }
 153 
 154   LayoutKind kind() const {
 155     assert(_kind != LayoutKind::UNKNOWN, "Not set");
 156     return _kind;
 157   }
 158   void set_kind(LayoutKind lk) { _kind = lk; }
 159 
 160   int null_marker_offset() const {
 161     assert(_null_marker_offset != -1, "Not set");
 162     return _null_marker_offset;
 163   }
 164   void set_null_marker_offset(int o) { _null_marker_offset = o; }
 165 
 166   void metaspace_pointers_do(MetaspaceClosure* it);
 167   MetaspaceObj::Type type() const { return InlineLayoutInfoType; }
 168 
 169   static ByteSize klass_offset() { return byte_offset_of(InlineLayoutInfo, _klass); }
 170   static ByteSize null_marker_offset_offset() { return byte_offset_of(InlineLayoutInfo, _null_marker_offset); }
 171 };
 172 
 173 class InstanceKlass: public Klass {
 174   friend class VMStructs;
 175   friend class JVMCIVMStructs;
 176   friend class ClassFileParser;
 177   friend class CompileReplay;
 178   friend class TemplateTable;
 179 
 180  public:
 181   static const KlassKind Kind = InstanceKlassKind;
 182 
 183  protected:
 184   InstanceKlass(const ClassFileParser& parser, KlassKind kind = Kind, markWord prototype = markWord::prototype(), ReferenceType reference_type = REF_NONE);
 185 
 186  public:
 187   InstanceKlass();
 188 
 189   // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
 190   // of the class loading & initialization procedure, and the use of the states.
 191   enum ClassState : u1 {
 192     allocated,                          // allocated (but not yet linked)
 193     loaded,                             // loaded and inserted in class hierarchy (but not linked yet)
 194     linked,                             // successfully linked/verified (but not initialized yet)
 195     being_initialized,                  // currently running class initializer
 196     fully_initialized,                  // initialized (successful final state)
 197     initialization_error                // error happened during initialization
 198   };
 199 
 200  private:
 201   static InstanceKlass* allocate_instance_klass(const ClassFileParser& parser, TRAPS);
 202 
 203  protected:
 204   // If you add a new field that points to any metaspace object, you
 205   // must add this field to InstanceKlass::metaspace_pointers_do().
 206 
 207   // Annotations for this class
 208   Annotations*    _annotations;
 209   // Package this class is defined in
 210   PackageEntry*   _package_entry;
 211   // Array classes holding elements of this class.
 212   ObjArrayKlass* volatile _array_klasses;
 213   // Constant pool for this class.
 214   ConstantPool* _constants;
 215   // The InnerClasses attribute and EnclosingMethod attribute. The
 216   // _inner_classes is an array of shorts. If the class has InnerClasses
 217   // attribute, then the _inner_classes array begins with 4-tuples of shorts
 218   // [inner_class_info_index, outer_class_info_index,
 219   // inner_name_index, inner_class_access_flags] for the InnerClasses
 220   // attribute. If the EnclosingMethod attribute exists, it occupies the
 221   // last two shorts [class_index, method_index] of the array. If only
 222   // the InnerClasses attribute exists, the _inner_classes array length is
 223   // number_of_inner_classes * 4. If the class has both InnerClasses
 224   // and EnclosingMethod attributes the _inner_classes array length is
 225   // number_of_inner_classes * 4 + enclosing_method_attribute_size.
 226   Array<jushort>* _inner_classes;
 227 
 228   // The NestMembers attribute. An array of shorts, where each is a
 229   // class info index for the class that is a nest member. This data
 230   // has not been validated.
 231   Array<jushort>* _nest_members;
 232 
 233   // Resolved nest-host klass: either true nest-host or self if we are not
 234   // nested, or an error occurred resolving or validating the nominated
 235   // nest-host. Can also be set directly by JDK API's that establish nest
 236   // relationships.
 237   // By always being set it makes nest-member access checks simpler.
 238   InstanceKlass* _nest_host;
 239 
 240   // The PermittedSubclasses attribute. An array of shorts, where each is a
 241   // class info index for the class that is a permitted subclass.
 242   Array<jushort>* _permitted_subclasses;
 243 
 244   // The contents of the Record attribute.
 245   Array<RecordComponent*>* _record_components;
 246 
 247   // the source debug extension for this klass, null if not specified.
 248   // Specified as UTF-8 string without terminating zero byte in the classfile,
 249   // it is stored in the instanceklass as a null-terminated UTF-8 string
 250   const char*     _source_debug_extension;
 251 
 252   // Number of heapOopSize words used by non-static fields in this klass
 253   // (including inherited fields but after header_size()).
 254   int             _nonstatic_field_size;
 255   int             _static_field_size;       // number words used by static fields (oop and non-oop) in this klass
 256   int             _nonstatic_oop_map_size;  // size in words of nonstatic oop map blocks
 257   int             _itable_len;              // length of Java itable (in words)
 258 
 259   // The NestHost attribute. The class info index for the class
 260   // that is the nest-host of this class. This data has not been validated.
 261   u2              _nest_host_index;
 262   u2              _this_class_index;        // constant pool entry
 263   u2              _static_oop_field_count;  // number of static oop fields in this klass
 264 
 265   volatile u2     _idnum_allocated_count;   // JNI/JVMTI: increments with the addition of methods, old ids don't change
 266 
 267   // Class states are defined as ClassState (see above).
 268   // Place the _init_state here to utilize the unused 2-byte after
 269   // _idnum_allocated_count.
 270   volatile ClassState _init_state;          // state of class
 271 
 272   u1              _reference_type;          // reference type
 273   int             _acmp_maps_offset;        // offset to injected static field storing acmp_maps for values classes
 274                                             // unfortunately, abstract values need one too so it cannot be stored in
 275                                             // the InlineKlass::Members that only exist for InlineKlass.
 276 
 277   AccessFlags        _access_flags;    // Access flags. The class/interface distinction is stored here.
 278 
 279   // State is set either at parse time or while executing, atomically to not disturb other state
 280   InstanceKlassFlags _misc_flags;
 281 
 282   JavaThread* volatile _init_thread;        // Pointer to current thread doing initialization (to handle recursive initialization)
 283 
 284   OopMapCache*    volatile _oop_map_cache;   // OopMapCache for all methods in the klass (allocated lazily)
 285   JNIid*          _jni_ids;                  // First JNI identifier for static fields in this class
 286   jmethodID* volatile _methods_jmethod_ids;  // jmethodIDs corresponding to method_idnum, or null if none
 287   nmethodBucket*  volatile _dep_context;     // packed DependencyContext structure
 288   uint64_t        volatile _dep_context_last_cleaned;
 289   nmethod*        _osr_nmethods_head;    // Head of list of on-stack replacement nmethods for this class
 290 #if INCLUDE_JVMTI
 291   BreakpointInfo* _breakpoints;          // bpt lists, managed by Method*
 292   // Linked instanceKlasses of previous versions
 293   InstanceKlass* _previous_versions;
 294   // JVMTI fields can be moved to their own structure - see 6315920
 295   // JVMTI: cached class file, before retransformable agent modified it in CFLH
 296   JvmtiCachedClassFileData* _cached_class_file;
 297 #endif
 298 
 299 #if INCLUDE_JVMTI
 300   JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map;  // JVMTI: used during heap iteration
 301 #endif
 302 
 303   NOT_PRODUCT(int _verify_count;)  // to avoid redundant verifies
 304   NOT_PRODUCT(volatile int _shared_class_load_count;) // ensure a shared class is loaded only once
 305 
 306   // Method array.
 307   Array<Method*>* _methods;
 308   // Default Method Array, concrete methods inherited from interfaces
 309   Array<Method*>* _default_methods;
 310   // Interfaces (InstanceKlass*s) this class declares locally to implement.
 311   Array<InstanceKlass*>* _local_interfaces;
 312   // Interfaces (InstanceKlass*s) this class implements transitively.
 313   Array<InstanceKlass*>* _transitive_interfaces;
 314   // Int array containing the original order of method in the class file (for JVMTI).
 315   Array<int>*     _method_ordering;
 316   // Int array containing the vtable_indices for default_methods
 317   // offset matches _default_methods offset
 318   Array<int>*     _default_vtable_indices;
 319 
 320   // Fields information is stored in an UNSIGNED5 encoded stream (see fieldInfo.hpp)
 321   Array<u1>*          _fieldinfo_stream;
 322   Array<u1>*          _fieldinfo_search_table;
 323   Array<FieldStatus>* _fields_status;
 324 
 325   Array<InlineLayoutInfo>* _inline_layout_info_array;
 326   Array<u2>* _loadable_descriptors;
 327 
 328   // Located here because sub-klasses can't have their own C++ fields
 329   address _adr_inline_klass_members;
 330 
 331   // embedded Java vtable follows here
 332   // embedded Java itables follows here
 333   // embedded static fields follows here
 334   // embedded nonstatic oop-map blocks follows here
 335   // embedded implementor of this interface follows here
 336   //   The embedded implementor only exists if the current klass is an
 337   //   interface. The possible values of the implementor fall into following
 338   //   three cases:
 339   //     null: no implementor.
 340   //     A Klass* that's not itself: one implementor.
 341   //     Itself: more than one implementors.
 342   //
 343 
 344   friend class SystemDictionary;
 345 
 346   static bool _disable_method_binary_search;
 347 
 348   // Controls finalizer registration
 349   static bool _finalization_enabled;
 350 
 351  public:
 352 
 353   // Queries finalization state
 354   static bool is_finalization_enabled() { return _finalization_enabled; }
 355 
 356   // Sets finalization state
 357   static void set_finalization_enabled(bool val) { _finalization_enabled = val; }
 358 
 359   // Access flags
 360   AccessFlags access_flags() const         { return _access_flags;  }
 361   void set_access_flags(AccessFlags flags) { _access_flags = flags; }
 362 
 363   bool is_public() const                { return _access_flags.is_public(); }
 364   bool is_final() const                 { return _access_flags.is_final(); }
 365   bool is_interface() const override    { return _access_flags.is_interface(); }
 366   bool is_abstract() const override     { return _access_flags.is_abstract(); }
 367   bool is_synthetic() const             { return _access_flags.is_synthetic(); }
 368   void set_is_synthetic()               { _access_flags.set_is_synthetic(); }
 369   bool is_identity_class() const override { return _access_flags.is_identity_class(); }
 370 
 371   static ByteSize access_flags_offset() { return byte_offset_of(InstanceKlass, _access_flags); }
 372 
 373   void set_is_cloneable();
 374 
 375   // Quick checks for the loader that defined this class (without switching on this->class_loader())
 376   bool defined_by_boot_loader() const      { return _misc_flags.defined_by_boot_loader(); }
 377   bool defined_by_platform_loader() const  { return _misc_flags.defined_by_platform_loader(); }
 378   bool defined_by_app_loader() const       { return _misc_flags.defined_by_app_loader(); }
 379   bool defined_by_other_loaders() const    { return _misc_flags.defined_by_other_loaders(); }
 380   void set_class_loader_type()             { _misc_flags.set_class_loader_type(_class_loader_data); }
 381 
 382   // Check if the class can be shared in CDS
 383   bool is_shareable() const;
 384 
 385   bool shared_loading_failed() const { return _misc_flags.shared_loading_failed(); }
 386 
 387   void set_shared_loading_failed() { _misc_flags.set_shared_loading_failed(true); }
 388 
 389   bool has_nonstatic_fields() const        { return _misc_flags.has_nonstatic_fields(); }
 390   void set_has_nonstatic_fields(bool b)    { _misc_flags.set_has_nonstatic_fields(b); }
 391 
 392   bool has_localvariable_table() const     { return _misc_flags.has_localvariable_table(); }
 393   void set_has_localvariable_table(bool b) { _misc_flags.set_has_localvariable_table(b); }
 394 
 395   bool has_inline_type_fields() const { return _misc_flags.has_inline_type_fields(); }
 396   void set_has_inline_type_fields()   { _misc_flags.set_has_inline_type_fields(true); }
 397 
 398   bool is_naturally_atomic() const  { return _misc_flags.is_naturally_atomic(); }
 399   void set_is_naturally_atomic()    { _misc_flags.set_is_naturally_atomic(true); }
 400 
 401   // Query if this class has atomicity requirements (default is yes)
 402   // This bit can occur anywhere, but is only significant
 403   // for inline classes *and* their super types.
 404   // It inherits from supers.
 405   // Its value depends on the ForceNonTearable VM option, the LooselyConsistentValue annotation
 406   // and the presence of flat fields with atomicity requirements
 407   bool must_be_atomic() const { return _misc_flags.must_be_atomic(); }
 408   void set_must_be_atomic()   { _misc_flags.set_must_be_atomic(true); }
 409 
 410   // field sizes
 411   int nonstatic_field_size() const         { return _nonstatic_field_size; }
 412   void set_nonstatic_field_size(int size)  { _nonstatic_field_size = size; }
 413 
 414   int static_field_size() const            { return _static_field_size; }
 415   void set_static_field_size(int size)     { _static_field_size = size; }
 416 
 417   int static_oop_field_count() const       { return (int)_static_oop_field_count; }
 418   void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
 419 
 420   // Java itable
 421   int  itable_length() const               { return _itable_len; }
 422   void set_itable_length(int len)          { _itable_len = len; }
 423 
 424   // array klasses
 425   ObjArrayKlass* array_klasses() const     { return _array_klasses; }
 426   inline ObjArrayKlass* array_klasses_acquire() const; // load with acquire semantics
 427   inline void release_set_array_klasses(ObjArrayKlass* k); // store with release semantics
 428   void set_array_klasses(ObjArrayKlass* k) { _array_klasses = k; }
 429 
 430   // methods
 431   Array<Method*>* methods() const          { return _methods; }
 432   void set_methods(Array<Method*>* a)      { _methods = a; }
 433   Method* method_with_idnum(int idnum) const;
 434   Method* method_with_orig_idnum(int idnum) const;
 435   Method* method_with_orig_idnum(int idnum, int version) const;
 436 
 437   // method ordering
 438   Array<int>* method_ordering() const     { return _method_ordering; }
 439   void set_method_ordering(Array<int>* m) { _method_ordering = m; }
 440   void copy_method_ordering(const intArray* m, TRAPS);
 441 
 442   // default_methods
 443   Array<Method*>* default_methods() const  { return _default_methods; }
 444   void set_default_methods(Array<Method*>* a) { _default_methods = a; }
 445 
 446   // default method vtable_indices
 447   Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
 448   void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
 449   Array<int>* create_new_default_vtable_indices(int len, TRAPS);
 450 
 451   // interfaces
 452   Array<InstanceKlass*>* local_interfaces() const          { return _local_interfaces; }
 453   void set_local_interfaces(Array<InstanceKlass*>* a)      {
 454     guarantee(_local_interfaces == nullptr || a == nullptr, "Just checking");
 455     _local_interfaces = a; }
 456 
 457   Array<InstanceKlass*>* transitive_interfaces() const     { return _transitive_interfaces; }
 458   void set_transitive_interfaces(Array<InstanceKlass*>* a) {
 459     guarantee(_transitive_interfaces == nullptr || a == nullptr, "Just checking");
 460     _transitive_interfaces = a;
 461   }
 462 
 463  private:
 464   friend class fieldDescriptor;
 465   FieldInfo field(int index) const;
 466 
 467  public:
 468   int     field_offset      (int index) const { return field(index).offset(); }
 469   int     field_access_flags(int index) const { return field(index).access_flags().as_field_flags(); }
 470   FieldInfo::FieldFlags field_flags(int index) const { return field(index).field_flags(); }
 471   FieldStatus field_status(int index)   const { return fields_status()->at(index); }
 472   inline Symbol* field_name        (int index) const;
 473   inline Symbol* field_signature   (int index) const;
 474   bool field_is_flat(int index) const { return field_flags(index).is_flat(); }
 475   bool field_has_null_marker(int index) const { return field_flags(index).has_null_marker(); }
 476   bool field_is_null_free_inline_type(int index) const;
 477   bool is_class_in_loadable_descriptors_attribute(Symbol* name) const;
 478 
 479   int null_marker_offset(int index) const { return inline_layout_info(index).null_marker_offset(); }
 480 
 481   // Number of Java declared fields
 482   int java_fields_count() const;
 483   int total_fields_count() const;
 484 
 485   Array<u1>* fieldinfo_stream() const { return _fieldinfo_stream; }
 486   void set_fieldinfo_stream(Array<u1>* fis) { _fieldinfo_stream = fis; }
 487 
 488   Array<u1>* fieldinfo_search_table() const { return _fieldinfo_search_table; }
 489   void set_fieldinfo_search_table(Array<u1>* table) { _fieldinfo_search_table = table; }
 490 
 491   Array<FieldStatus>* fields_status() const {return _fields_status; }
 492   void set_fields_status(Array<FieldStatus>* array) { _fields_status = array; }
 493 
 494   Array<u2>* loadable_descriptors() const { return _loadable_descriptors; }
 495   void set_loadable_descriptors(Array<u2>* c) { _loadable_descriptors = c; }
 496 
 497   // inner classes
 498   Array<u2>* inner_classes() const       { return _inner_classes; }
 499   void set_inner_classes(Array<u2>* f)   { _inner_classes = f; }
 500 
 501   // nest members
 502   Array<u2>* nest_members() const     { return _nest_members; }
 503   void set_nest_members(Array<u2>* m) { _nest_members = m; }
 504 
 505   // nest-host index
 506   jushort nest_host_index() const { return _nest_host_index; }
 507   void set_nest_host_index(u2 i)  { _nest_host_index = i; }
 508   // dynamic nest member support
 509   void set_nest_host(InstanceKlass* host);
 510 
 511   // record components
 512   Array<RecordComponent*>* record_components() const { return _record_components; }
 513   void set_record_components(Array<RecordComponent*>* record_components) {
 514     _record_components = record_components;
 515   }
 516   bool is_record() const;
 517 
 518   // test for enum class (or possibly an anonymous subclass within a sealed enum)
 519   bool is_enum_subclass() const;
 520 
 521   // permitted subclasses
 522   Array<u2>* permitted_subclasses() const     { return _permitted_subclasses; }
 523   void set_permitted_subclasses(Array<u2>* s) { _permitted_subclasses = s; }
 524 
 525 private:
 526   // Called to verify that k is a member of this nest - does not look at k's nest-host,
 527   // nor does it resolve any CP entries or load any classes.
 528   bool has_nest_member(JavaThread* current, InstanceKlass* k) const;
 529 
 530 public:
 531   // Call this only if you know that the nest host has been initialized.
 532   InstanceKlass* nest_host_not_null() {
 533     assert(_nest_host != nullptr, "must be");
 534     return _nest_host;
 535   }
 536   InstanceKlass* nest_host_or_null() {
 537     return _nest_host;
 538   }
 539   // Used to construct informative IllegalAccessError messages at a higher level,
 540   // if there was an issue resolving or validating the nest host.
 541   // Returns null if there was no error.
 542   const char* nest_host_error();
 543   // Returns nest-host class, resolving and validating it if needed.
 544   // Returns null if resolution is not possible from the calling context.
 545   InstanceKlass* nest_host(TRAPS);
 546   // Check if this klass is a nestmate of k - resolves this nest-host and k's
 547   bool has_nestmate_access_to(InstanceKlass* k, TRAPS);
 548 
 549   // Called to verify that k is a permitted subclass of this class.
 550   // The incoming stringStream is used for logging, and for the caller to create
 551   // a detailed exception message on failure.
 552   bool has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const;
 553 
 554   enum InnerClassAttributeOffset {
 555     // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
 556     inner_class_inner_class_info_offset = 0,
 557     inner_class_outer_class_info_offset = 1,
 558     inner_class_inner_name_offset = 2,
 559     inner_class_access_flags_offset = 3,
 560     inner_class_next_offset = 4
 561   };
 562 
 563   enum EnclosingMethodAttributeOffset {
 564     enclosing_method_class_index_offset = 0,
 565     enclosing_method_method_index_offset = 1,
 566     enclosing_method_attribute_size = 2
 567   };
 568 
 569   // package
 570   PackageEntry* package() const override { return _package_entry; }
 571   ModuleEntry* module() const override;
 572   bool in_javabase_module() const;
 573   bool in_unnamed_package() const   { return (_package_entry == nullptr); }
 574   void set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS);
 575   // If the package for the InstanceKlass is in the boot loader's package entry
 576   // table then sets the classpath_index field so that
 577   // get_system_package() will know to return a non-null value for the
 578   // package's location.  And, so that the package will be added to the list of
 579   // packages returned by get_system_packages().
 580   // For packages whose classes are loaded from the boot loader class path, the
 581   // classpath_index indicates which entry on the boot loader class path.
 582   void set_classpath_index(s2 path_index);
 583   bool is_same_class_package(const Klass* class2) const;
 584   bool is_same_class_package(oop other_class_loader, const Symbol* other_class_name) const;
 585 
 586   // find an enclosing class
 587   InstanceKlass* compute_enclosing_class(bool* inner_is_member, TRAPS) const;
 588 
 589   // Find InnerClasses attribute and return outer_class_info_index & inner_name_index.
 590   bool find_inner_classes_attr(int* ooff, int* noff, TRAPS) const;
 591 
 592   // Check if this klass can be null-free
 593   static void check_can_be_annotated_with_NullRestricted(InstanceKlass* type, Symbol* container_klass_name, TRAPS);
 594 
 595  private:
 596   // Check prohibited package ("java/" only loadable by boot or platform loaders)
 597   static void check_prohibited_package(Symbol* class_name,
 598                                        ClassLoaderData* loader_data,
 599                                        TRAPS);
 600 
 601   JavaThread* init_thread()  { return AtomicAccess::load(&_init_thread); }
 602   const char* init_thread_name() {
 603     return init_thread()->name_raw();
 604   }
 605 
 606  public:
 607   // initialization state
 608   bool is_loaded() const                   { return init_state() >= loaded; }
 609   bool is_linked() const                   { return init_state() >= linked; }
 610   bool is_initialized() const              { return init_state() == fully_initialized; }
 611   bool is_not_initialized() const          { return init_state() <  being_initialized; }
 612   bool is_being_initialized() const        { return init_state() == being_initialized; }
 613   bool is_in_error_state() const           { return init_state() == initialization_error; }
 614   bool is_reentrant_initialization(Thread *thread)  { return thread == _init_thread; }
 615   ClassState  init_state() const           { return AtomicAccess::load_acquire(&_init_state); }
 616   const char* init_state_name() const;
 617   bool is_rewritten() const                { return _misc_flags.rewritten(); }
 618 
 619   // is this a sealed class
 620   bool is_sealed() const;
 621 
 622   // defineClass specified verification
 623   bool should_verify_class() const         { return _misc_flags.should_verify_class(); }
 624   void set_should_verify_class(bool value) { _misc_flags.set_should_verify_class(value); }
 625 
 626   // marking
 627   bool is_marked_dependent() const         { return _misc_flags.is_marked_dependent(); }
 628   void set_is_marked_dependent(bool value) { _misc_flags.set_is_marked_dependent(value); }
 629 
 630   static ByteSize kind_offset() { return byte_offset_of(InstanceKlass, _kind); }
 631   static ByteSize misc_flags_offset() { return byte_offset_of(InstanceKlass, _misc_flags); }
 632 
 633   // initialization (virtuals from Klass)
 634   bool should_be_initialized() const override;  // means that initialize should be called
 635   void initialize_with_aot_initialized_mirror(TRAPS);
 636   void assert_no_clinit_will_run_for_aot_initialized_class() const NOT_DEBUG_RETURN;
 637   void initialize(TRAPS) override;
 638   void initialize_preemptable(TRAPS) override;
 639   void link_class(TRAPS);
 640   bool link_class_or_fail(TRAPS); // returns false on failure
 641   void rewrite_class(TRAPS);
 642   void link_methods(TRAPS);
 643   Method* class_initializer() const;
 644   bool interface_needs_clinit_execution_as_super(bool also_check_supers=true) const;
 645 
 646   // reference type
 647   ReferenceType reference_type() const     { return (ReferenceType)_reference_type; }
 648 
 649   int acmp_maps_offset() const {
 650     assert(_acmp_maps_offset != 0, "Not initialized");
 651     return _acmp_maps_offset;
 652   }
 653   void set_acmp_maps_offset(int offset) { _acmp_maps_offset = offset; }
 654   static ByteSize acmp_maps_offset_offset() { return byte_offset_of(InstanceKlass, _acmp_maps_offset); }
 655 
 656   // this class cp index
 657   u2 this_class_index() const             { return _this_class_index; }
 658   void set_this_class_index(u2 index)     { _this_class_index = index; }
 659 
 660   static ByteSize reference_type_offset() { return byte_offset_of(InstanceKlass, _reference_type); }
 661 
 662   // find local field, returns true if found
 663   bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 664   // find field in direct superinterfaces, returns the interface in which the field is defined
 665   Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 666   // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 667   Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const override;
 668   // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 669   Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
 670 
 671   // find a non-static or static field given its offset within the class.
 672   bool contains_field_offset(int offset);
 673 
 674   bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 675   bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 676 
 677  private:
 678   inline static int quick_search(const Array<Method*>* methods, const Symbol* name);
 679 
 680  public:
 681   static void disable_method_binary_search() {
 682     _disable_method_binary_search = true;
 683   }
 684 
 685   // find a local method (returns null if not found)
 686   Method* find_method(const Symbol* name, const Symbol* signature) const;
 687   static Method* find_method(const Array<Method*>* methods,
 688                              const Symbol* name,
 689                              const Symbol* signature);
 690 
 691   // find a local method, but skip static methods
 692   Method* find_instance_method(const Symbol* name, const Symbol* signature,
 693                                PrivateLookupMode private_mode) const;
 694   static Method* find_instance_method(const Array<Method*>* methods,
 695                                       const Symbol* name,
 696                                       const Symbol* signature,
 697                                       PrivateLookupMode private_mode);
 698 
 699   // find a local method (returns null if not found)
 700   Method* find_local_method(const Symbol* name,
 701                             const Symbol* signature,
 702                             OverpassLookupMode overpass_mode,
 703                             StaticLookupMode static_mode,
 704                             PrivateLookupMode private_mode) const;
 705 
 706   // find a local method from given methods array (returns null if not found)
 707   static Method* find_local_method(const Array<Method*>* methods,
 708                                    const Symbol* name,
 709                                    const Symbol* signature,
 710                                    OverpassLookupMode overpass_mode,
 711                                    StaticLookupMode static_mode,
 712                                    PrivateLookupMode private_mode);
 713 
 714   // find a local method index in methods or default_methods (returns -1 if not found)
 715   static int find_method_index(const Array<Method*>* methods,
 716                                const Symbol* name,
 717                                const Symbol* signature,
 718                                OverpassLookupMode overpass_mode,
 719                                StaticLookupMode static_mode,
 720                                PrivateLookupMode private_mode);
 721 
 722   // lookup operation (returns null if not found)
 723   Method* uncached_lookup_method(const Symbol* name,
 724                                  const Symbol* signature,
 725                                  OverpassLookupMode overpass_mode,
 726                                  PrivateLookupMode private_mode = PrivateLookupMode::find) const override;
 727 
 728   // lookup a method in all the interfaces that this class implements
 729   // (returns null if not found)
 730   Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, DefaultsLookupMode defaults_mode) const;
 731 
 732   // lookup a method in local defaults then in all interfaces
 733   // (returns null if not found)
 734   Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
 735 
 736   // Find method indices by name.  If a method with the specified name is
 737   // found the index to the first method is returned, and 'end' is filled in
 738   // with the index of first non-name-matching method.  If no method is found
 739   // -1 is returned.
 740   int find_method_by_name(const Symbol* name, int* end) const;
 741   static int find_method_by_name(const Array<Method*>* methods,
 742                                  const Symbol* name, int* end);
 743 
 744   // constant pool
 745   ConstantPool* constants() const        { return _constants; }
 746   void set_constants(ConstantPool* c)    { _constants = c; }
 747 
 748   // protection domain
 749   oop protection_domain() const override;
 750 
 751   // signers
 752   objArrayOop signers() const;
 753 
 754   bool is_contended() const                { return _misc_flags.is_contended(); }
 755   void set_is_contended(bool value)        { _misc_flags.set_is_contended(value); }
 756 
 757   // source file name
 758   Symbol* source_file_name() const;
 759   u2 source_file_name_index() const;
 760   void set_source_file_name_index(u2 sourcefile_index);
 761 
 762   // minor and major version numbers of class file
 763   u2 minor_version() const;
 764   void set_minor_version(u2 minor_version);
 765   u2 major_version() const;
 766   void set_major_version(u2 major_version);
 767 
 768   bool supports_inline_types() const;
 769 
 770   // source debug extension
 771   const char* source_debug_extension() const { return _source_debug_extension; }
 772   void set_source_debug_extension(const char* array, int length);
 773 
 774   // nonstatic oop-map blocks
 775   static int nonstatic_oop_map_size(unsigned int oop_map_count) {
 776     return oop_map_count * OopMapBlock::size_in_words();
 777   }
 778   unsigned int nonstatic_oop_map_count() const {
 779     return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
 780   }
 781   int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
 782   void set_nonstatic_oop_map_size(int words) {
 783     _nonstatic_oop_map_size = words;
 784   }
 785 
 786   bool has_contended_annotations() const { return _misc_flags.has_contended_annotations(); }
 787   void set_has_contended_annotations(bool value)  { _misc_flags.set_has_contended_annotations(value); }
 788 
 789 #if INCLUDE_JVMTI
 790   // Redefinition locking.  Class can only be redefined by one thread at a time.
 791   bool is_being_redefined() const          { return _misc_flags.is_being_redefined(); }
 792   void set_is_being_redefined(bool value)  { _misc_flags.set_is_being_redefined(value); }
 793 
 794   // RedefineClasses() support for previous versions:
 795   void add_previous_version(InstanceKlass* ik, int emcp_method_count);
 796   void purge_previous_version_list();
 797 
 798   InstanceKlass* previous_versions() const { return _previous_versions; }
 799 #else
 800   InstanceKlass* previous_versions() const { return nullptr; }
 801 #endif
 802 
 803   const InstanceKlass* get_klass_version(int version) const;
 804 
 805   bool has_been_redefined() const { return _misc_flags.has_been_redefined(); }
 806   void set_has_been_redefined() { _misc_flags.set_has_been_redefined(true); }
 807 
 808   bool is_scratch_class() const { return _misc_flags.is_scratch_class(); }
 809   void set_is_scratch_class() { _misc_flags.set_is_scratch_class(true); }
 810 
 811   bool has_resolved_methods() const { return _misc_flags.has_resolved_methods(); }
 812   void set_has_resolved_methods()   { _misc_flags.set_has_resolved_methods(true); }
 813   void set_has_resolved_methods(bool value)   { _misc_flags.set_has_resolved_methods(value); }
 814 
 815 public:
 816 #if INCLUDE_JVMTI
 817 
 818   void init_previous_versions() {
 819     _previous_versions = nullptr;
 820   }
 821 
 822  private:
 823   static bool  _should_clean_previous_versions;
 824  public:
 825   static void purge_previous_versions(InstanceKlass* ik) {
 826     if (ik->has_been_redefined()) {
 827       ik->purge_previous_version_list();
 828     }
 829   }
 830 
 831   static bool should_clean_previous_versions_and_reset();
 832   static bool should_clean_previous_versions() { return _should_clean_previous_versions; }
 833 
 834   // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
 835   void set_cached_class_file(JvmtiCachedClassFileData *data) {
 836     _cached_class_file = data;
 837   }
 838   JvmtiCachedClassFileData * get_cached_class_file();
 839   jint get_cached_class_file_len();
 840   unsigned char * get_cached_class_file_bytes();
 841 
 842   // JVMTI: Support for caching of field indices, types, and offsets
 843   void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
 844     _jvmti_cached_class_field_map = descriptor;
 845   }
 846   JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
 847     return _jvmti_cached_class_field_map;
 848   }
 849 #else // INCLUDE_JVMTI
 850 
 851   static void purge_previous_versions(InstanceKlass* ik) { return; };
 852   static bool should_clean_previous_versions_and_reset() { return false; }
 853 
 854   void set_cached_class_file(JvmtiCachedClassFileData *data) {
 855     assert(data == nullptr, "unexpected call with JVMTI disabled");
 856   }
 857   JvmtiCachedClassFileData * get_cached_class_file() { return (JvmtiCachedClassFileData *)nullptr; }
 858 
 859 #endif // INCLUDE_JVMTI
 860 
 861   bool has_nonstatic_concrete_methods() const { return _misc_flags.has_nonstatic_concrete_methods(); }
 862   void set_has_nonstatic_concrete_methods(bool b) { _misc_flags.set_has_nonstatic_concrete_methods(b); }
 863 
 864   bool declares_nonstatic_concrete_methods() const { return _misc_flags.declares_nonstatic_concrete_methods(); }
 865   void set_declares_nonstatic_concrete_methods(bool b) { _misc_flags.set_declares_nonstatic_concrete_methods(b); }
 866 
 867   bool has_miranda_methods () const     { return _misc_flags.has_miranda_methods(); }
 868   void set_has_miranda_methods()        { _misc_flags.set_has_miranda_methods(true); }
 869   bool has_final_method() const         { return _misc_flags.has_final_method(); }
 870   void set_has_final_method()           { _misc_flags.set_has_final_method(true); }
 871 
 872   // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
 873   inline u2 next_method_idnum();
 874   void set_initial_method_idnum(u2 value)             { _idnum_allocated_count = value; }
 875 
 876   // runtime support for strict statics
 877   bool has_strict_static_fields() const     { return _misc_flags.has_strict_static_fields(); }
 878   void set_has_strict_static_fields(bool b) { _misc_flags.set_has_strict_static_fields(b); }
 879   void notify_strict_static_access(int field_index, bool is_writing, TRAPS);
 880   const char* format_strict_static_message(Symbol* field_name, const char* doing_what = nullptr);
 881   void throw_strict_static_exception(Symbol* field_name, const char* when, TRAPS);
 882 
 883   // generics support
 884   Symbol* generic_signature() const;
 885   u2 generic_signature_index() const;
 886   void set_generic_signature_index(u2 sig_index);
 887 
 888   u2 enclosing_method_data(int offset) const;
 889   u2 enclosing_method_class_index() const {
 890     return enclosing_method_data(enclosing_method_class_index_offset);
 891   }
 892   u2 enclosing_method_method_index() {
 893     return enclosing_method_data(enclosing_method_method_index_offset);
 894   }
 895   void set_enclosing_method_indices(u2 class_index,
 896                                     u2 method_index);
 897 
 898   // jmethodID support
 899   jmethodID get_jmethod_id(Method* method);
 900   void make_methods_jmethod_ids();
 901   jmethodID jmethod_id_or_null(Method* method);
 902   void update_methods_jmethod_cache();
 903 
 904   // annotations support
 905   Annotations* annotations() const          { return _annotations; }
 906   void set_annotations(Annotations* anno)   { _annotations = anno; }
 907 
 908   AnnotationArray* class_annotations() const {
 909     return (_annotations != nullptr) ? _annotations->class_annotations() : nullptr;
 910   }
 911   Array<AnnotationArray*>* fields_annotations() const {
 912     return (_annotations != nullptr) ? _annotations->fields_annotations() : nullptr;
 913   }
 914   AnnotationArray* class_type_annotations() const {
 915     return (_annotations != nullptr) ? _annotations->class_type_annotations() : nullptr;
 916   }
 917   Array<AnnotationArray*>* fields_type_annotations() const {
 918     return (_annotations != nullptr) ? _annotations->fields_type_annotations() : nullptr;
 919   }
 920   // allocation
 921   instanceOop allocate_instance(TRAPS);
 922   static instanceOop allocate_instance(oop cls, TRAPS);
 923 
 924   // additional member function to return a handle
 925   instanceHandle allocate_instance_handle(TRAPS);
 926 
 927   // Helper function
 928   static instanceOop register_finalizer(instanceOop i, TRAPS);
 929 
 930   // Check whether reflection/jni/jvm code is allowed to instantiate this class;
 931   // if not, throw either an Error or an Exception.
 932   void check_valid_for_instantiation(bool throwError, TRAPS) override;
 933 
 934   // initialization
 935   void call_class_initializer(TRAPS);
 936   void set_initialization_state_and_notify(ClassState state, TRAPS);
 937 
 938   // OopMapCache support
 939   OopMapCache* oop_map_cache()               { return _oop_map_cache; }
 940   void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
 941   void mask_for(const methodHandle& method, int bci, InterpreterOopMap* entry);
 942 
 943   // JNI identifier support (for static fields - for jni performance)
 944   JNIid* jni_ids()                               { return _jni_ids; }
 945   void set_jni_ids(JNIid* ids)                   { _jni_ids = ids; }
 946   JNIid* jni_id_for(int offset);
 947 
 948  public:
 949   // maintenance of deoptimization dependencies
 950   inline DependencyContext dependencies();
 951   void mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes);
 952   void add_dependent_nmethod(nmethod* nm);
 953   void clean_dependency_context();
 954   // Setup link to hierarchy and deoptimize
 955   void add_to_hierarchy(JavaThread* current);
 956 
 957   // On-stack replacement support
 958   nmethod* osr_nmethods_head() const         { return _osr_nmethods_head; };
 959   void set_osr_nmethods_head(nmethod* h)     { _osr_nmethods_head = h; };
 960   void add_osr_nmethod(nmethod* n);
 961   bool remove_osr_nmethod(nmethod* n);
 962   int mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m);
 963   nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
 964 
 965 #if INCLUDE_JVMTI
 966   // Breakpoint support (see methods on Method* for details)
 967   BreakpointInfo* breakpoints() const       { return _breakpoints; };
 968   void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
 969 #endif
 970 
 971   // support for stub routines
 972   static ByteSize init_state_offset()  { return byte_offset_of(InstanceKlass, _init_state); }
 973   JFR_ONLY(DEFINE_KLASS_TRACE_ID_OFFSET;)
 974   static ByteSize init_thread_offset() { return byte_offset_of(InstanceKlass, _init_thread); }
 975 
 976   static ByteSize inline_layout_info_array_offset() { return byte_offset_of(InstanceKlass, _inline_layout_info_array); }
 977   static ByteSize adr_inline_klass_members_offset() { return byte_offset_of(InstanceKlass, _adr_inline_klass_members); }
 978 
 979   // subclass/subinterface checks
 980   bool implements_interface(Klass* k) const;
 981   bool is_same_or_direct_interface(Klass* k) const;
 982 
 983 #ifdef ASSERT
 984   // check whether this class or one of its superclasses was redefined
 985   bool has_redefined_this_or_super() const;
 986 #endif
 987 
 988   // Access to the implementor of an interface.
 989   InstanceKlass* implementor() const;
 990   void set_implementor(InstanceKlass* ik);
 991   int  nof_implementors() const;
 992   void add_implementor(InstanceKlass* ik);  // ik is a new class that implements this interface
 993   void init_implementor();           // initialize
 994 
 995  private:
 996   // link this class into the implementors list of every interface it implements
 997   void process_interfaces();
 998 
 999  public:
1000   // virtual operations from Klass
1001   GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
1002                                                   Array<InstanceKlass*>* transitive_interfaces) override;
1003   bool can_be_primary_super_slow() const override;
1004   size_t oop_size(oop obj)  const override    { return size_helper(); }
1005   // slow because it's a virtual call and used for verifying the layout_helper.
1006   // Using the layout_helper bits, we can call is_instance_klass without a virtual call.
1007   DEBUG_ONLY(bool is_instance_klass_slow() const override { return true; })
1008 
1009   // Iterators
1010   void do_local_static_fields(FieldClosure* cl);
1011   void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
1012   void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
1013   void print_nonstatic_fields(FieldClosure* cl); // including inherited and injected fields
1014 
1015   void methods_do(void f(Method* method));
1016 
1017   static InstanceKlass* cast(Klass* k) {
1018     return const_cast<InstanceKlass*>(cast(const_cast<const Klass*>(k)));
1019   }
1020 
1021   static const InstanceKlass* cast(const Klass* k) {
1022     assert(k != nullptr, "k should not be null");
1023     assert(k->is_instance_klass(), "cast to InstanceKlass");
1024     return static_cast<const InstanceKlass*>(k);
1025   }
1026 
1027   // This hides Klass::super(). The _super of an InstanceKlass is
1028   // always an InstanceKlass (or nullptr)
1029   InstanceKlass* super() const {
1030     return (Klass::super() == nullptr) ? nullptr : InstanceKlass::cast(Klass::super());
1031   }
1032 
1033   InstanceKlass* java_super() const override {
1034     return InstanceKlass::super();
1035   }
1036 
1037   // Sizing (in words)
1038   static int header_size() { return sizeof(InstanceKlass) / wordSize; }
1039 
1040   static int size(int vtable_length,
1041                   int itable_length,
1042                   int nonstatic_oop_map_size,
1043                   bool is_interface,
1044                   bool is_inline_type);
1045 
1046   int size() const override;
1047 
1048   inline intptr_t* start_of_itable() const;
1049   inline intptr_t* end_of_itable() const;
1050   inline oop static_field_base_raw();
1051   bool bounds_check(address addr, bool edge_ok = false, intptr_t size_in_bytes = -1) const PRODUCT_RETURN0;
1052 
1053   inline OopMapBlock* start_of_nonstatic_oop_maps() const;
1054   inline Klass** end_of_nonstatic_oop_maps() const;
1055 
1056   inline InstanceKlass* volatile* adr_implementor() const;
1057 
1058   // The end of the memory block that belongs to this InstanceKlass.
1059   // Sub-klasses can place their fields after this address.
1060   inline address end_of_instance_klass() const;
1061 
1062   void set_inline_layout_info_array(Array<InlineLayoutInfo>* array) { _inline_layout_info_array = array; }
1063   Array<InlineLayoutInfo>* inline_layout_info_array() const { return _inline_layout_info_array; }
1064   void set_inline_layout_info(int index, InlineLayoutInfo *info) {
1065     assert(_inline_layout_info_array != nullptr ,"Array not created");
1066     _inline_layout_info_array->at_put(index, *info);
1067   }
1068   InlineLayoutInfo inline_layout_info(int index) const {
1069     assert(_inline_layout_info_array != nullptr ,"Array not created");
1070     return _inline_layout_info_array->at(index);
1071   }
1072   InlineLayoutInfo* inline_layout_info_adr(int index) {
1073     assert(_inline_layout_info_array != nullptr ,"Array not created");
1074     return _inline_layout_info_array->adr_at(index);
1075   }
1076 
1077   inline InlineKlass* get_inline_type_field_klass(int idx) const ;
1078   inline InlineKlass* get_inline_type_field_klass_or_null(int idx) const;
1079 
1080   // Use this to return the size of an instance in heap words:
1081   int size_helper() const {
1082     return layout_helper_to_size_helper(layout_helper());
1083   }
1084 
1085   // This bit is initialized in classFileParser.cpp.
1086   // It is false under any of the following conditions:
1087   //  - the class is abstract (including any interface)
1088   //  - the class size is larger than FastAllocateSizeLimit
1089   //  - the class is java/lang/Class, which cannot be allocated directly
1090   bool can_be_fastpath_allocated() const {
1091     return !layout_helper_needs_slow_path(layout_helper());
1092   }
1093 
1094   // Java itable
1095   klassItable itable() const;        // return klassItable wrapper
1096   Method* method_at_itable(InstanceKlass* holder, int index, TRAPS);
1097   Method* method_at_itable_or_null(InstanceKlass* holder, int index, bool& itable_entry_found);
1098   int vtable_index_of_interface_method(Method* method);
1099 
1100 #if INCLUDE_JVMTI
1101   void adjust_default_methods(bool* trace_name_printed);
1102 #endif // INCLUDE_JVMTI
1103 
1104   void clean_weak_instanceklass_links();
1105  private:
1106   void clean_implementors_list();
1107   void clean_method_data();
1108 
1109  public:
1110   // Explicit metaspace deallocation of fields
1111   // For RedefineClasses and class file parsing errors, we need to deallocate
1112   // instanceKlasses and the metadata they point to.
1113   void deallocate_contents(ClassLoaderData* loader_data);
1114   static void deallocate_methods(ClassLoaderData* loader_data,
1115                                  Array<Method*>* methods);
1116   void static deallocate_interfaces(ClassLoaderData* loader_data,
1117                                     const InstanceKlass* super_klass,
1118                                     Array<InstanceKlass*>* local_interfaces,
1119                                     Array<InstanceKlass*>* transitive_interfaces);
1120   void static deallocate_record_components(ClassLoaderData* loader_data,
1121                                            Array<RecordComponent*>* record_component);
1122 
1123   bool on_stack() const override;
1124 
1125   // callbacks for actions during class unloading
1126   static void unload_class(InstanceKlass* ik);
1127 
1128   void release_C_heap_structures(bool release_sub_metadata = true) override;
1129 
1130   // Naming
1131   const char* signature_name() const override;
1132   const char* signature_name_of_carrier(char c) const;
1133 
1134   // Oop fields (and metadata) iterators
1135   //
1136   // The InstanceKlass iterators also visits the Object's klass.
1137 
1138   // Forward iteration
1139  public:
1140   // Iterate over all oop fields in the oop maps.
1141   template <typename T, class OopClosureType>
1142   inline void oop_oop_iterate_oop_maps(oop obj, OopClosureType* closure);
1143 
1144   // Iterate over all oop fields and metadata.
1145   template <typename T, class OopClosureType>
1146   inline void oop_oop_iterate(oop obj, OopClosureType* closure);
1147 
1148   // Iterate over all oop fields in one oop map.
1149   template <typename T, class OopClosureType>
1150   inline void oop_oop_iterate_oop_map(OopMapBlock* map, oop obj, OopClosureType* closure);
1151 
1152 
1153   // Reverse iteration
1154   // Iterate over all oop fields and metadata.
1155   template <typename T, class OopClosureType>
1156   inline void oop_oop_iterate_reverse(oop obj, OopClosureType* closure);
1157 
1158  private:
1159   // Iterate over all oop fields in the oop maps.
1160   template <typename T, class OopClosureType>
1161   inline void oop_oop_iterate_oop_maps_reverse(oop obj, OopClosureType* closure);
1162 
1163   // Iterate over all oop fields in one oop map.
1164   template <typename T, class OopClosureType>
1165   inline void oop_oop_iterate_oop_map_reverse(OopMapBlock* map, oop obj, OopClosureType* closure);
1166 
1167 
1168   // Bounded range iteration
1169  public:
1170   // Iterate over all oop fields in the oop maps.
1171   template <typename T, class OopClosureType>
1172   inline void oop_oop_iterate_oop_maps_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1173 
1174   // Iterate over all oop fields and metadata.
1175   template <typename T, class OopClosureType>
1176   inline void oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1177 
1178  private:
1179   // Iterate over all oop fields in one oop map.
1180   template <typename T, class OopClosureType>
1181   inline void oop_oop_iterate_oop_map_bounded(OopMapBlock* map, oop obj, OopClosureType* closure, MemRegion mr);
1182 
1183 
1184  public:
1185   u2 idnum_allocated_count() const      { return _idnum_allocated_count; }
1186 
1187 private:
1188   // initialization state
1189   void set_init_state(ClassState state);
1190   void set_rewritten()                  { _misc_flags.set_rewritten(true); }
1191   void set_init_thread(JavaThread *thread)  {
1192     assert((thread == JavaThread::current() && _init_thread == nullptr) ||
1193            (thread == nullptr && _init_thread == JavaThread::current()), "Only one thread is allowed to own initialization");
1194     AtomicAccess::store(&_init_thread, thread);
1195   }
1196 
1197   jmethodID* methods_jmethod_ids_acquire() const;
1198   void release_set_methods_jmethod_ids(jmethodID* jmeths);
1199   // This nulls out obsolete jmethodIDs for all methods in 'klass'.
1200   static void clear_obsolete_jmethod_ids(InstanceKlass* klass);
1201   jmethodID update_jmethod_id(jmethodID* jmeths, Method* method, int idnum);
1202 
1203 public:
1204   // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1205   // Must be one per class and it has to be a VM internal object so java code
1206   // cannot lock it (like the mirror).
1207   // It has to be an object not a Mutex because it's held through java calls.
1208   oop init_lock() const;
1209 
1210   // Returns the array class for the n'th dimension
1211   ArrayKlass* array_klass(int n, TRAPS) override;
1212   ArrayKlass* array_klass_or_null(int n) override;
1213 
1214   // Returns the array class with this class as element type
1215   ArrayKlass* array_klass(TRAPS) override;
1216   ArrayKlass* array_klass_or_null() override;
1217 
1218   static void clean_initialization_error_table();
1219 private:
1220   void fence_and_clear_init_lock();
1221 
1222   bool link_class_impl                           (TRAPS);
1223   bool verify_code                               (TRAPS);
1224   void initialize_impl                           (TRAPS);
1225   void initialize_super_interfaces               (TRAPS);
1226 
1227   void add_initialization_error(JavaThread* current, Handle exception);
1228   oop get_initialization_error(JavaThread* current);
1229 
1230   // find a local method (returns null if not found)
1231   Method* find_method_impl(const Symbol* name,
1232                            const Symbol* signature,
1233                            OverpassLookupMode overpass_mode,
1234                            StaticLookupMode static_mode,
1235                            PrivateLookupMode private_mode) const;
1236 
1237   static Method* find_method_impl(const Array<Method*>* methods,
1238                                   const Symbol* name,
1239                                   const Symbol* signature,
1240                                   OverpassLookupMode overpass_mode,
1241                                   StaticLookupMode static_mode,
1242                                   PrivateLookupMode private_mode);
1243 
1244 #if INCLUDE_JVMTI
1245   // RedefineClasses support
1246   void link_previous_versions(InstanceKlass* pv) { _previous_versions = pv; }
1247   void mark_newly_obsolete_methods(Array<Method*>* old_methods, int emcp_method_count);
1248 #endif
1249   // log class name to classlist
1250   void log_to_classlist() const;
1251 public:
1252 
1253 #if INCLUDE_CDS
1254   // CDS support - remove and restore oops from metadata. Oops are not shared.
1255   void remove_unshareable_info() override;
1256   void remove_unshareable_flags();
1257   void remove_java_mirror() override;
1258   virtual void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, PackageEntry* pkg_entry, TRAPS);
1259   void init_shared_package_entry();
1260   bool can_be_verified_at_dumptime() const;
1261   void compute_has_loops_flag_for_methods();
1262 #endif
1263   bool     has_init_deps_processed() const { return _misc_flags.has_init_deps_processed(); }
1264   void set_has_init_deps_processed() {
1265     assert(is_initialized(), "");
1266     assert(!has_init_deps_processed(), "already set"); // one-off action
1267     _misc_flags.set_has_init_deps_processed(true);
1268   }
1269 
1270   u2 compute_modifier_flags() const override;
1271 
1272 public:
1273   // JVMTI support
1274   jint jvmti_class_status() const override;
1275 
1276   void metaspace_pointers_do(MetaspaceClosure* iter) override;
1277 
1278  public:
1279   // Printing
1280   void print_on(outputStream* st) const override;
1281   void print_value_on(outputStream* st) const override;
1282 
1283   void oop_print_value_on(oop obj, outputStream* st) override;
1284 
1285   void oop_print_on      (oop obj, outputStream* st) override { oop_print_on(obj, st, 0, 0); }
1286   void oop_print_on      (oop obj, outputStream* st, int indent = 0, int base_offset = 0);
1287 
1288 #ifndef PRODUCT
1289   void print_dependent_nmethods(bool verbose = false);
1290   bool is_dependent_nmethod(nmethod* nm);
1291   bool verify_itable_index(int index);
1292 #endif
1293 
1294   const char* internal_name() const override;
1295 
1296   // Verification
1297   void verify_on(outputStream* st) override;
1298 
1299   void oop_verify_on(oop obj, outputStream* st) override;
1300 
1301   // Logging
1302   void print_class_load_logging(ClassLoaderData* loader_data,
1303                                 const ModuleEntry* module_entry,
1304                                 const ClassFileStream* cfs) const;
1305  private:
1306   void print_class_load_cause_logging() const;
1307   void print_class_load_helper(ClassLoaderData* loader_data,
1308                                const ModuleEntry* module_entry,
1309                                const ClassFileStream* cfs) const;
1310 };
1311 
1312 // for adding methods
1313 // UNSET_IDNUM return means no more ids available
1314 inline u2 InstanceKlass::next_method_idnum() {
1315   if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1316     return ConstMethod::UNSET_IDNUM; // no more ids available
1317   } else {
1318     return _idnum_allocated_count++;
1319   }
1320 }
1321 
1322 class PrintClassClosure : public KlassClosure {
1323 private:
1324   outputStream* _st;
1325   bool _verbose;
1326 public:
1327   PrintClassClosure(outputStream* st, bool verbose);
1328 
1329   void do_klass(Klass* k);
1330 };
1331 
1332 /* JNIid class for jfieldIDs only */
1333 class JNIid: public CHeapObj<mtClass> {
1334   friend class VMStructs;
1335  private:
1336   InstanceKlass*     _holder;
1337   JNIid*             _next;
1338   int                _offset;
1339 #ifdef ASSERT
1340   bool               _is_static_field_id;
1341 #endif
1342 
1343  public:
1344   // Accessors
1345   InstanceKlass* holder() const   { return _holder; }
1346   int offset() const              { return _offset; }
1347   JNIid* next()                   { return _next; }
1348   // Constructor
1349   JNIid(InstanceKlass* holder, int offset, JNIid* next);
1350   // Identifier lookup
1351   JNIid* find(int offset);
1352 
1353   bool find_local_field(fieldDescriptor* fd) {
1354     return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1355   }
1356 
1357   static void deallocate(JNIid* id);
1358   // Debugging
1359 #ifdef ASSERT
1360   bool is_static_field_id() const { return _is_static_field_id; }
1361   void set_is_static_field_id()   { _is_static_field_id = true; }
1362 #endif
1363   void verify(InstanceKlass* holder);
1364 };
1365 
1366 // An iterator that's used to access the inner classes indices in the
1367 // InstanceKlass::_inner_classes array.
1368 class InnerClassesIterator : public StackObj {
1369  private:
1370   Array<jushort>* _inner_classes;
1371   int _length;
1372   int _idx;
1373  public:
1374 
1375   InnerClassesIterator(const InstanceKlass* k) {
1376     _inner_classes = k->inner_classes();
1377     if (k->inner_classes() != nullptr) {
1378       _length = _inner_classes->length();
1379       // The inner class array's length should be the multiple of
1380       // inner_class_next_offset if it only contains the InnerClasses
1381       // attribute data, or it should be
1382       // n*inner_class_next_offset+enclosing_method_attribute_size
1383       // if it also contains the EnclosingMethod data.
1384       assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1385               _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1386              "just checking");
1387       // Remove the enclosing_method portion if exists.
1388       if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1389         _length -= InstanceKlass::enclosing_method_attribute_size;
1390       }
1391     } else {
1392       _length = 0;
1393     }
1394     _idx = 0;
1395   }
1396 
1397   int length() const {
1398     return _length;
1399   }
1400 
1401   void next() {
1402     _idx += InstanceKlass::inner_class_next_offset;
1403   }
1404 
1405   bool done() const {
1406     return (_idx >= _length);
1407   }
1408 
1409   u2 inner_class_info_index() const {
1410     return _inner_classes->at(
1411                _idx + InstanceKlass::inner_class_inner_class_info_offset);
1412   }
1413 
1414   void set_inner_class_info_index(u2 index) {
1415     _inner_classes->at_put(
1416                _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1417   }
1418 
1419   u2 outer_class_info_index() const {
1420     return _inner_classes->at(
1421                _idx + InstanceKlass::inner_class_outer_class_info_offset);
1422   }
1423 
1424   void set_outer_class_info_index(u2 index) {
1425     _inner_classes->at_put(
1426                _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1427   }
1428 
1429   u2 inner_name_index() const {
1430     return _inner_classes->at(
1431                _idx + InstanceKlass::inner_class_inner_name_offset);
1432   }
1433 
1434   void set_inner_name_index(u2 index) {
1435     _inner_classes->at_put(
1436                _idx + InstanceKlass::inner_class_inner_name_offset, index);
1437   }
1438 
1439   u2 inner_access_flags() const {
1440     return _inner_classes->at(
1441                _idx + InstanceKlass::inner_class_access_flags_offset);
1442   }
1443 };
1444 
1445 // Iterator over class hierarchy under a particular class. Implements depth-first pre-order traversal.
1446 // Usage:
1447 //  for (ClassHierarchyIterator iter(root_klass); !iter.done(); iter.next()) {
1448 //    Klass* k = iter.klass();
1449 //    ...
1450 //  }
1451 class ClassHierarchyIterator : public StackObj {
1452  private:
1453   InstanceKlass* _root;
1454   Klass*         _current;
1455   bool           _visit_subclasses;
1456 
1457  public:
1458   ClassHierarchyIterator(InstanceKlass* root) : _root(root), _current(root), _visit_subclasses(true) {
1459     assert(_root == _current, "required"); // initial state
1460   }
1461 
1462   bool done() {
1463     return (_current == nullptr);
1464   }
1465 
1466   // Make a step iterating over the class hierarchy under the root class.
1467   // Skips subclasses if requested.
1468   void next();
1469 
1470   Klass* klass() {
1471     assert(!done(), "sanity");
1472     return _current;
1473   }
1474 
1475   // Skip subclasses of the current class.
1476   void skip_subclasses() {
1477     _visit_subclasses = false;
1478   }
1479 };
1480 
1481 #endif // SHARE_OOPS_INSTANCEKLASS_HPP