1 /*
   2  * Copyright (c) 1997, 2026, 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 "memory/allocation.hpp"
  29 #include "memory/referenceType.hpp"
  30 #include "oops/annotations.hpp"
  31 #include "oops/constMethod.hpp"
  32 #include "oops/fieldInfo.hpp"
  33 #include "oops/instanceKlassFlags.hpp"
  34 #include "oops/instanceOop.hpp"
  35 #include "runtime/handles.hpp"
  36 #include "runtime/javaThread.hpp"
  37 #include "utilities/accessFlags.hpp"
  38 #include "utilities/align.hpp"
  39 #include "utilities/growableArray.hpp"
  40 #include "utilities/macros.hpp"
  41 #if INCLUDE_JFR
  42 #include "jfr/support/jfrKlassExtension.hpp"
  43 #endif
  44 
  45 class ConstantPool;
  46 class DeoptimizationScope;
  47 class klassItable;
  48 class RecordComponent;
  49 
  50 // An InstanceKlass is the VM level representation of a Java class.
  51 // It contains all information needed for at class at execution runtime.
  52 
  53 //  InstanceKlass embedded field layout (after declared fields):
  54 //    [EMBEDDED Java vtable             ] size in words = vtable_len
  55 //    [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
  56 //      The embedded nonstatic oop-map blocks are short pairs (offset, length)
  57 //      indicating where oops are located in instances of this klass.
  58 //    [EMBEDDED implementor of the interface] only exist for interface
  59 
  60 
  61 // forward declaration for class -- see below for definition
  62 #if INCLUDE_JVMTI
  63 class BreakpointInfo;
  64 #endif
  65 class ClassFileParser;
  66 class ClassFileStream;
  67 class KlassDepChange;
  68 class DependencyContext;
  69 class fieldDescriptor;
  70 class JNIid;
  71 class JvmtiCachedClassFieldMap;
  72 class nmethodBucket;
  73 class OopMapCache;
  74 class InterpreterOopMap;
  75 class PackageEntry;
  76 class ModuleEntry;
  77 
  78 // This is used in iterators below.
  79 class FieldClosure: public StackObj {
  80 public:
  81   virtual void do_field(fieldDescriptor* fd) = 0;
  82 };
  83 
  84 // Print fields.
  85 // If "obj" argument to constructor is null, prints static fields, otherwise prints non-static fields.
  86 class FieldPrinter: public FieldClosure {
  87    oop _obj;
  88    outputStream* _st;
  89  public:
  90    FieldPrinter(outputStream* st, oop obj = nullptr) : _obj(obj), _st(st) {}
  91    void do_field(fieldDescriptor* fd);
  92 };
  93 
  94 // Describes where oops are located in instances of this klass.
  95 class OopMapBlock {
  96  public:
  97   // Byte offset of the first oop mapped by this block.
  98   int offset() const          { return _offset; }
  99   void set_offset(int offset) { _offset = offset; }
 100 
 101   // Number of oops in this block.
 102   uint count() const         { return _count; }
 103   void set_count(uint count) { _count = count; }
 104 
 105   void increment_count(int diff) { _count += diff; }
 106 
 107   int offset_span() const { return _count * heapOopSize; }
 108 
 109   int end_offset() const {
 110     return offset() + offset_span();
 111   }
 112 
 113   bool is_contiguous(int another_offset) const {
 114     return another_offset == end_offset();
 115   }
 116 
 117   // sizeof(OopMapBlock) in words.
 118   static int size_in_words() {
 119     return align_up((int)sizeof(OopMapBlock), wordSize) >>
 120       LogBytesPerWord;
 121   }
 122 
 123   static int compare_offset(const OopMapBlock* a, const OopMapBlock* b) {
 124     return a->offset() - b->offset();
 125   }
 126 
 127  private:
 128   int  _offset;
 129   uint _count;
 130 };
 131 
 132 struct JvmtiCachedClassFileData;
 133 
 134 class InstanceKlass: public Klass {
 135   friend class VMStructs;
 136   friend class ClassFileParser;
 137   friend class CompileReplay;
 138 
 139  public:
 140   static const KlassKind Kind = InstanceKlassKind;
 141 
 142  protected:
 143   InstanceKlass(const ClassFileParser& parser, KlassKind kind = Kind, ReferenceType reference_type = REF_NONE);
 144 
 145  public:
 146   InstanceKlass();
 147 
 148   // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
 149   // of the class loading & initialization procedure, and the use of the states.
 150   enum ClassState : u1 {
 151     allocated,                          // allocated (but not yet linked)
 152     loaded,                             // loaded and inserted in class hierarchy (but not linked yet)
 153     linked,                             // successfully linked/verified (but not initialized yet)
 154     being_initialized,                  // currently running class initializer
 155     fully_initialized,                  // initialized (successful final state)
 156     initialization_error                // error happened during initialization
 157   };
 158 
 159  private:
 160   static InstanceKlass* allocate_instance_klass(const ClassFileParser& parser, TRAPS);
 161 
 162  protected:
 163   // If you add a new field that points to any metaspace object, you
 164   // must add this field to InstanceKlass::metaspace_pointers_do().
 165 
 166   // Annotations for this class
 167   Annotations*    _annotations;
 168   // Package this class is defined in
 169   PackageEntry*   _package_entry;
 170   // Array classes holding elements of this class.
 171   ObjArrayKlass* volatile _array_klasses;
 172   // Constant pool for this class.
 173   ConstantPool* _constants;
 174   // The InnerClasses attribute and EnclosingMethod attribute. The
 175   // _inner_classes is an array of shorts. If the class has InnerClasses
 176   // attribute, then the _inner_classes array begins with 4-tuples of shorts
 177   // [inner_class_info_index, outer_class_info_index,
 178   // inner_name_index, inner_class_access_flags] for the InnerClasses
 179   // attribute. If the EnclosingMethod attribute exists, it occupies the
 180   // last two shorts [class_index, method_index] of the array. If only
 181   // the InnerClasses attribute exists, the _inner_classes array length is
 182   // number_of_inner_classes * 4. If the class has both InnerClasses
 183   // and EnclosingMethod attributes the _inner_classes array length is
 184   // number_of_inner_classes * 4 + enclosing_method_attribute_size.
 185   Array<jushort>* _inner_classes;
 186 
 187   // The NestMembers attribute. An array of shorts, where each is a
 188   // class info index for the class that is a nest member. This data
 189   // has not been validated.
 190   Array<jushort>* _nest_members;
 191 
 192   // Resolved nest-host klass: either true nest-host or self if we are not
 193   // nested, or an error occurred resolving or validating the nominated
 194   // nest-host. Can also be set directly by JDK API's that establish nest
 195   // relationships.
 196   // By always being set it makes nest-member access checks simpler.
 197   InstanceKlass* _nest_host;
 198 
 199   // The PermittedSubclasses attribute. An array of shorts, where each is a
 200   // class info index for the class that is a permitted subclass.
 201   Array<jushort>* _permitted_subclasses;
 202 
 203   // The contents of the Record attribute.
 204   Array<RecordComponent*>* _record_components;
 205 
 206   // the source debug extension for this klass, null if not specified.
 207   // Specified as UTF-8 string without terminating zero byte in the classfile,
 208   // it is stored in the instanceklass as a null-terminated UTF-8 string
 209   const char*     _source_debug_extension;
 210 
 211   // Number of heapOopSize words used by non-static fields in this klass
 212   // (including inherited fields but after header_size()).
 213   int             _nonstatic_field_size;
 214   int             _static_field_size;       // number words used by static fields (oop and non-oop) in this klass
 215   int             _nonstatic_oop_map_size;  // size in words of nonstatic oop map blocks
 216   int             _itable_len;              // length of Java itable (in words)
 217 
 218   // The NestHost attribute. The class info index for the class
 219   // that is the nest-host of this class. This data has not been validated.
 220   u2              _nest_host_index;
 221   u2              _this_class_index;        // constant pool entry
 222   u2              _static_oop_field_count;  // number of static oop fields in this klass
 223 
 224   volatile u2     _idnum_allocated_count;   // JNI/JVMTI: increments with the addition of methods, old ids don't change
 225 
 226   // Class states are defined as ClassState (see above).
 227   // Place the _init_state here to utilize the unused 2-byte after
 228   // _idnum_allocated_count.
 229   volatile ClassState _init_state;          // state of class
 230 
 231   u1                 _reference_type;                // reference type
 232 
 233   AccessFlags        _access_flags;    // Access flags. The class/interface distinction is stored here.
 234 
 235   // State is set either at parse time or while executing, atomically to not disturb other state
 236   InstanceKlassFlags _misc_flags;
 237 
 238   JavaThread* volatile _init_thread;        // Pointer to current thread doing initialization (to handle recursive initialization)
 239 
 240   int             _hash_offset;             // Offset of hidden field for i-hash
 241 
 242   OopMapCache*    volatile _oop_map_cache;   // OopMapCache for all methods in the klass (allocated lazily)
 243   JNIid*          _jni_ids;                  // First JNI identifier for static fields in this class
 244   jmethodID* volatile _methods_jmethod_ids;  // jmethodIDs corresponding to method_idnum, or null if none
 245   nmethodBucket*  volatile _dep_context;     // packed DependencyContext structure
 246   uint64_t        volatile _dep_context_last_cleaned;
 247   nmethod*        _osr_nmethods_head;    // Head of list of on-stack replacement nmethods for this class
 248 #if INCLUDE_JVMTI
 249   BreakpointInfo* _breakpoints;          // bpt lists, managed by Method*
 250   // Linked instanceKlasses of previous versions
 251   InstanceKlass* _previous_versions;
 252   // JVMTI fields can be moved to their own structure - see 6315920
 253   // JVMTI: cached class file, before retransformable agent modified it in CFLH
 254   JvmtiCachedClassFileData* _cached_class_file;
 255 #endif
 256 
 257 #if INCLUDE_JVMTI
 258   JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map;  // JVMTI: used during heap iteration
 259 #endif
 260 
 261   NOT_PRODUCT(int _verify_count;)  // to avoid redundant verifies
 262   NOT_PRODUCT(volatile int _shared_class_load_count;) // ensure a shared class is loaded only once
 263 
 264   // Method array.
 265   Array<Method*>* _methods;
 266   // Default Method Array, concrete methods inherited from interfaces
 267   Array<Method*>* _default_methods;
 268   // Interfaces (InstanceKlass*s) this class declares locally to implement.
 269   Array<InstanceKlass*>* _local_interfaces;
 270   // Interfaces (InstanceKlass*s) this class implements transitively.
 271   Array<InstanceKlass*>* _transitive_interfaces;
 272   // Int array containing the original order of method in the class file (for JVMTI).
 273   Array<int>*     _method_ordering;
 274   // Int array containing the vtable_indices for default_methods
 275   // offset matches _default_methods offset
 276   Array<int>*     _default_vtable_indices;
 277 
 278   // Fields information is stored in an UNSIGNED5 encoded stream (see fieldInfo.hpp)
 279   Array<u1>*          _fieldinfo_stream;
 280   Array<u1>*          _fieldinfo_search_table;
 281   Array<FieldStatus>* _fields_status;
 282 
 283   // embedded Java vtable follows here
 284   // embedded Java itables follows here
 285   // embedded static fields follows here
 286   // embedded nonstatic oop-map blocks follows here
 287   // embedded implementor of this interface follows here
 288   //   The embedded implementor only exists if the current klass is an
 289   //   interface. The possible values of the implementor fall into following
 290   //   three cases:
 291   //     null: no implementor.
 292   //     A Klass* that's not itself: one implementor.
 293   //     Itself: more than one implementors.
 294   //
 295 
 296   friend class SystemDictionary;
 297 
 298   static bool _disable_method_binary_search;
 299 
 300   // Controls finalizer registration
 301   static bool _finalization_enabled;
 302 
 303  public:
 304 
 305   // Queries finalization state
 306   static bool is_finalization_enabled() { return _finalization_enabled; }
 307 
 308   // Sets finalization state
 309   static void set_finalization_enabled(bool val) { _finalization_enabled = val; }
 310 
 311   // Access flags
 312   AccessFlags access_flags() const         { return _access_flags;  }
 313   void set_access_flags(AccessFlags flags) { _access_flags = flags; }
 314 
 315   bool is_public() const                { return _access_flags.is_public(); }
 316   bool is_final() const                 { return _access_flags.is_final(); }
 317   bool is_interface() const override    { return _access_flags.is_interface(); }
 318   bool is_abstract() const override     { return _access_flags.is_abstract(); }
 319   bool is_super() const                 { return _access_flags.is_super(); }
 320   bool is_synthetic() const             { return _access_flags.is_synthetic(); }
 321   void set_is_synthetic()               { _access_flags.set_is_synthetic(); }
 322 
 323   static ByteSize access_flags_offset() { return byte_offset_of(InstanceKlass, _access_flags); }
 324 
 325   void set_is_cloneable();
 326 
 327   // Quick checks for the loader that defined this class (without switching on this->class_loader())
 328   bool defined_by_boot_loader() const      { return _misc_flags.defined_by_boot_loader(); }
 329   bool defined_by_platform_loader() const  { return _misc_flags.defined_by_platform_loader(); }
 330   bool defined_by_app_loader() const       { return _misc_flags.defined_by_app_loader(); }
 331   bool defined_by_other_loaders() const    { return _misc_flags.defined_by_other_loaders(); }
 332   void set_class_loader_type()             { _misc_flags.set_class_loader_type(_class_loader_data); }
 333 
 334   bool shared_loading_failed() const { return _misc_flags.shared_loading_failed(); }
 335 
 336   void set_shared_loading_failed() { _misc_flags.set_shared_loading_failed(true); }
 337 
 338   bool has_nonstatic_fields() const        { return _misc_flags.has_nonstatic_fields(); }
 339   void set_has_nonstatic_fields(bool b)    { _misc_flags.set_has_nonstatic_fields(b); }
 340 
 341   bool has_localvariable_table() const     { return _misc_flags.has_localvariable_table(); }
 342   void set_has_localvariable_table(bool b) { _misc_flags.set_has_localvariable_table(b); }
 343 
 344   // field sizes
 345   int nonstatic_field_size() const         { return _nonstatic_field_size; }
 346   void set_nonstatic_field_size(int size)  { _nonstatic_field_size = size; }
 347 
 348   int static_field_size() const            { return _static_field_size; }
 349   void set_static_field_size(int size)     { _static_field_size = size; }
 350 
 351   int static_oop_field_count() const       { return (int)_static_oop_field_count; }
 352   void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
 353 
 354   bool trust_final_fields()                { return _misc_flags.trust_final_fields(); }
 355   void set_trust_final_fields(bool value)  { _misc_flags.set_trust_final_fields(value); }
 356 
 357   // Java itable
 358   int  itable_length() const               { return _itable_len; }
 359   void set_itable_length(int len)          { _itable_len = len; }
 360 
 361   // array klasses
 362   ObjArrayKlass* array_klasses() const     { return _array_klasses; }
 363   inline ObjArrayKlass* array_klasses_acquire() const; // load with acquire semantics
 364   inline void release_set_array_klasses(ObjArrayKlass* k); // store with release semantics
 365   void set_array_klasses(ObjArrayKlass* k) { _array_klasses = k; }
 366 
 367   // methods
 368   Array<Method*>* methods() const          { return _methods; }
 369   void set_methods(Array<Method*>* a)      { _methods = a; }
 370   Method* method_with_idnum(int idnum) const;
 371   Method* method_with_orig_idnum(int idnum) const;
 372   Method* method_with_orig_idnum(int idnum, int version) const;
 373 
 374   // method ordering
 375   Array<int>* method_ordering() const     { return _method_ordering; }
 376   void set_method_ordering(Array<int>* m) { _method_ordering = m; }
 377   void copy_method_ordering(const intArray* m, TRAPS);
 378 
 379   // default_methods
 380   Array<Method*>* default_methods() const  { return _default_methods; }
 381   void set_default_methods(Array<Method*>* a) { _default_methods = a; }
 382 
 383   // default method vtable_indices
 384   Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
 385   void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
 386   Array<int>* create_new_default_vtable_indices(int len, TRAPS);
 387 
 388   // interfaces
 389   Array<InstanceKlass*>* local_interfaces() const          { return _local_interfaces; }
 390   void set_local_interfaces(Array<InstanceKlass*>* a)      {
 391     guarantee(_local_interfaces == nullptr || a == nullptr, "Just checking");
 392     _local_interfaces = a; }
 393 
 394   Array<InstanceKlass*>* transitive_interfaces() const     { return _transitive_interfaces; }
 395   void set_transitive_interfaces(Array<InstanceKlass*>* a) {
 396     guarantee(_transitive_interfaces == nullptr || a == nullptr, "Just checking");
 397     _transitive_interfaces = a;
 398   }
 399 
 400  private:
 401   friend class fieldDescriptor;
 402   FieldInfo field(int index) const;
 403 
 404  public:
 405   int     field_offset      (int index) const { return field(index).offset(); }
 406   int     field_access_flags(int index) const { return field(index).access_flags().as_field_flags(); }
 407   FieldInfo::FieldFlags field_flags(int index) const { return field(index).field_flags(); }
 408   FieldStatus field_status(int index)   const { return fields_status()->at(index); }
 409   inline Symbol* field_name        (int index) const;
 410   inline Symbol* field_signature   (int index) const;
 411 
 412   // Number of Java declared fields
 413   int java_fields_count() const;
 414   int total_fields_count() const;
 415 
 416   Array<u1>* fieldinfo_stream() const { return _fieldinfo_stream; }
 417   void set_fieldinfo_stream(Array<u1>* fis) { _fieldinfo_stream = fis; }
 418 
 419   Array<u1>* fieldinfo_search_table() const { return _fieldinfo_search_table; }
 420   void set_fieldinfo_search_table(Array<u1>* table) { _fieldinfo_search_table = table; }
 421 
 422   Array<FieldStatus>* fields_status() const {return _fields_status; }
 423   void set_fields_status(Array<FieldStatus>* array) { _fields_status = array; }
 424 
 425   // inner classes
 426   Array<u2>* inner_classes() const       { return _inner_classes; }
 427   void set_inner_classes(Array<u2>* f)   { _inner_classes = f; }
 428 
 429   // nest members
 430   Array<u2>* nest_members() const     { return _nest_members; }
 431   void set_nest_members(Array<u2>* m) { _nest_members = m; }
 432 
 433   // nest-host index
 434   jushort nest_host_index() const { return _nest_host_index; }
 435   void set_nest_host_index(u2 i)  { _nest_host_index = i; }
 436   // dynamic nest member support
 437   void set_nest_host(InstanceKlass* host);
 438 
 439   // record components
 440   Array<RecordComponent*>* record_components() const { return _record_components; }
 441   void set_record_components(Array<RecordComponent*>* record_components) {
 442     _record_components = record_components;
 443   }
 444   bool is_record() const;
 445 
 446   // test for enum class (or possibly an anonymous subclass within a sealed enum)
 447   bool is_enum_subclass() const;
 448 
 449   // permitted subclasses
 450   Array<u2>* permitted_subclasses() const     { return _permitted_subclasses; }
 451   void set_permitted_subclasses(Array<u2>* s) { _permitted_subclasses = s; }
 452 
 453 private:
 454   // Called to verify that k is a member of this nest - does not look at k's nest-host,
 455   // nor does it resolve any CP entries or load any classes.
 456   bool has_nest_member(JavaThread* current, InstanceKlass* k) const;
 457 
 458 public:
 459   // Call this only if you know that the nest host has been initialized.
 460   InstanceKlass* nest_host_not_null() {
 461     assert(_nest_host != nullptr, "must be");
 462     return _nest_host;
 463   }
 464   InstanceKlass* nest_host_or_null() {
 465     return _nest_host;
 466   }
 467   // Used to construct informative IllegalAccessError messages at a higher level,
 468   // if there was an issue resolving or validating the nest host.
 469   // Returns null if there was no error.
 470   const char* nest_host_error();
 471   // Returns nest-host class, resolving and validating it if needed.
 472   // Returns null if resolution is not possible from the calling context.
 473   InstanceKlass* nest_host(TRAPS);
 474   // Check if this klass is a nestmate of k - resolves this nest-host and k's
 475   bool has_nestmate_access_to(InstanceKlass* k, TRAPS);
 476 
 477   // Called to verify that k is a permitted subclass of this class.
 478   // The incoming stringStream is used for logging, and for the caller to create
 479   // a detailed exception message on failure.
 480   bool has_as_permitted_subclass(const InstanceKlass* k, stringStream& ss) const;
 481 
 482   enum InnerClassAttributeOffset {
 483     // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
 484     inner_class_inner_class_info_offset = 0,
 485     inner_class_outer_class_info_offset = 1,
 486     inner_class_inner_name_offset = 2,
 487     inner_class_access_flags_offset = 3,
 488     inner_class_next_offset = 4
 489   };
 490 
 491   enum EnclosingMethodAttributeOffset {
 492     enclosing_method_class_index_offset = 0,
 493     enclosing_method_method_index_offset = 1,
 494     enclosing_method_attribute_size = 2
 495   };
 496 
 497   // package
 498   PackageEntry* package() const override { return _package_entry; }
 499   ModuleEntry* module() const override;
 500   bool in_javabase_module() const;
 501   bool in_unnamed_package() const   { return (_package_entry == nullptr); }
 502   void set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS);
 503   // If the package for the InstanceKlass is in the boot loader's package entry
 504   // table then sets the classpath_index field so that
 505   // get_system_package() will know to return a non-null value for the
 506   // package's location.  And, so that the package will be added to the list of
 507   // packages returned by get_system_packages().
 508   // For packages whose classes are loaded from the boot loader class path, the
 509   // classpath_index indicates which entry on the boot loader class path.
 510   void set_classpath_index(s2 path_index);
 511   bool is_same_class_package(const Klass* class2) const;
 512   bool is_same_class_package(oop other_class_loader, const Symbol* other_class_name) const;
 513 
 514   // find an enclosing class
 515   InstanceKlass* compute_enclosing_class(bool* inner_is_member, TRAPS) const;
 516 
 517   // Find InnerClasses attribute and return outer_class_info_index & inner_name_index.
 518   bool find_inner_classes_attr(int* ooff, int* noff, TRAPS) const;
 519 
 520  private:
 521   // Check prohibited package ("java/" only loadable by boot or platform loaders)
 522   static void check_prohibited_package(Symbol* class_name,
 523                                        ClassLoaderData* loader_data,
 524                                        TRAPS);
 525 
 526   JavaThread* init_thread()  { return AtomicAccess::load(&_init_thread); }
 527   const char* init_thread_name() {
 528     return init_thread()->name_raw();
 529   }
 530 
 531  public:
 532   // initialization state
 533   bool is_loaded() const                   { return init_state() >= loaded; }
 534   bool is_linked() const                   { return init_state() >= linked; }
 535   bool is_initialized() const              { return init_state() == fully_initialized; }
 536   bool is_not_initialized() const          { return init_state() <  being_initialized; }
 537   bool is_being_initialized() const        { return init_state() == being_initialized; }
 538   bool is_in_error_state() const           { return init_state() == initialization_error; }
 539   bool is_reentrant_initialization(Thread *thread)  { return thread == _init_thread; }
 540   ClassState  init_state() const           { return AtomicAccess::load_acquire(&_init_state); }
 541   const char* init_state_name() const;
 542   bool is_rewritten() const                { return _misc_flags.rewritten(); }
 543 
 544   // is this a sealed class
 545   bool is_sealed() const;
 546 
 547   // defineClass specified verification
 548   bool should_verify_class() const         { return _misc_flags.should_verify_class(); }
 549   void set_should_verify_class(bool value) { _misc_flags.set_should_verify_class(value); }
 550 
 551   // marking
 552   bool is_marked_dependent() const         { return _misc_flags.is_marked_dependent(); }
 553   void set_is_marked_dependent(bool value) { _misc_flags.set_is_marked_dependent(value); }
 554 
 555   // initialization (virtuals from Klass)
 556   bool should_be_initialized() const override;  // means that initialize should be called
 557   void initialize_with_aot_initialized_mirror(bool early_init, TRAPS);
 558   void assert_no_clinit_will_run_for_aot_initialized_class() const NOT_DEBUG_RETURN;
 559   void initialize(TRAPS) override;
 560   void initialize_preemptable(TRAPS) override;
 561   void link_class(TRAPS);
 562   bool link_class_or_fail(TRAPS); // returns false on failure
 563   void rewrite_class(TRAPS);
 564   void link_methods(TRAPS);
 565   Method* class_initializer() const;
 566   bool interface_needs_clinit_execution_as_super(bool also_check_supers=true) const;
 567 
 568   // reference type
 569   ReferenceType reference_type() const     { return (ReferenceType)_reference_type; }
 570 
 571   // this class cp index
 572   u2 this_class_index() const             { return _this_class_index; }
 573   void set_this_class_index(u2 index)     { _this_class_index = index; }
 574 
 575   static ByteSize reference_type_offset() { return byte_offset_of(InstanceKlass, _reference_type); }
 576 
 577   // find local field, returns true if found
 578   bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 579   // find field in direct superinterfaces, returns the interface in which the field is defined
 580   Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 581   // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 582   Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const override;
 583   // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 584   Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
 585 
 586   // find a non-static or static field given its offset within the class.
 587   bool contains_field_offset(int offset);
 588 
 589   bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 590   bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 591 
 592  private:
 593   inline static int quick_search(const Array<Method*>* methods, const Symbol* name);
 594 
 595  public:
 596   static void disable_method_binary_search() {
 597     _disable_method_binary_search = true;
 598   }
 599 
 600   // find a local method (returns null if not found)
 601   Method* find_method(const Symbol* name, const Symbol* signature) const;
 602   static Method* find_method(const Array<Method*>* methods,
 603                              const Symbol* name,
 604                              const Symbol* signature);
 605 
 606   // find a local method, but skip static methods
 607   Method* find_instance_method(const Symbol* name, const Symbol* signature,
 608                                PrivateLookupMode private_mode) const;
 609   static Method* find_instance_method(const Array<Method*>* methods,
 610                                       const Symbol* name,
 611                                       const Symbol* signature,
 612                                       PrivateLookupMode private_mode);
 613 
 614   // find a local method (returns null if not found)
 615   Method* find_local_method(const Symbol* name,
 616                             const Symbol* signature,
 617                             OverpassLookupMode overpass_mode,
 618                             StaticLookupMode static_mode,
 619                             PrivateLookupMode private_mode) const;
 620 
 621   // find a local method from given methods array (returns null if not found)
 622   static Method* find_local_method(const Array<Method*>* methods,
 623                                    const Symbol* name,
 624                                    const Symbol* signature,
 625                                    OverpassLookupMode overpass_mode,
 626                                    StaticLookupMode static_mode,
 627                                    PrivateLookupMode private_mode);
 628 
 629   // find a local method index in methods or default_methods (returns -1 if not found)
 630   static int find_method_index(const Array<Method*>* methods,
 631                                const Symbol* name,
 632                                const Symbol* signature,
 633                                OverpassLookupMode overpass_mode,
 634                                StaticLookupMode static_mode,
 635                                PrivateLookupMode private_mode);
 636 
 637   // lookup operation (returns null if not found)
 638   Method* uncached_lookup_method(const Symbol* name,
 639                                  const Symbol* signature,
 640                                  OverpassLookupMode overpass_mode,
 641                                  PrivateLookupMode private_mode = PrivateLookupMode::find) const override;
 642 
 643   // lookup a method in all the interfaces that this class implements
 644   // (returns null if not found)
 645   Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, DefaultsLookupMode defaults_mode) const;
 646 
 647   // lookup a method in local defaults then in all interfaces
 648   // (returns null if not found)
 649   Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
 650 
 651   // Find method indices by name.  If a method with the specified name is
 652   // found the index to the first method is returned, and 'end' is filled in
 653   // with the index of first non-name-matching method.  If no method is found
 654   // -1 is returned.
 655   int find_method_by_name(const Symbol* name, int* end) const;
 656   static int find_method_by_name(const Array<Method*>* methods,
 657                                  const Symbol* name, int* end);
 658 
 659   // constant pool
 660   ConstantPool* constants() const        { return _constants; }
 661   void set_constants(ConstantPool* c)    { _constants = c; }
 662 
 663   // protection domain
 664   oop protection_domain() const override;
 665 
 666   // signers
 667   objArrayOop signers() const;
 668 
 669   bool is_contended() const                { return _misc_flags.is_contended(); }
 670   void set_is_contended(bool value)        { _misc_flags.set_is_contended(value); }
 671 
 672   // source file name
 673   Symbol* source_file_name() const;
 674   u2 source_file_name_index() const;
 675   void set_source_file_name_index(u2 sourcefile_index);
 676 
 677   // minor and major version numbers of class file
 678   u2 minor_version() const;
 679   void set_minor_version(u2 minor_version);
 680   u2 major_version() const;
 681   void set_major_version(u2 major_version);
 682 
 683   // source debug extension
 684   const char* source_debug_extension() const { return _source_debug_extension; }
 685   void set_source_debug_extension(const char* array, int length);
 686 
 687   // nonstatic oop-map blocks
 688   static int nonstatic_oop_map_size(unsigned int oop_map_count) {
 689     return oop_map_count * OopMapBlock::size_in_words();
 690   }
 691   unsigned int nonstatic_oop_map_count() const {
 692     return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
 693   }
 694   int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
 695   void set_nonstatic_oop_map_size(int words) {
 696     _nonstatic_oop_map_size = words;
 697   }
 698 
 699   bool has_contended_annotations() const { return _misc_flags.has_contended_annotations(); }
 700   void set_has_contended_annotations(bool value)  { _misc_flags.set_has_contended_annotations(value); }
 701 
 702 #if INCLUDE_JVMTI
 703   // Redefinition locking.  Class can only be redefined by one thread at a time.
 704   bool is_being_redefined() const          { return _misc_flags.is_being_redefined(); }
 705   void set_is_being_redefined(bool value)  { _misc_flags.set_is_being_redefined(value); }
 706 
 707   // RedefineClasses() support for previous versions:
 708   void add_previous_version(InstanceKlass* ik, int emcp_method_count);
 709   void purge_previous_version_list();
 710 
 711   InstanceKlass* previous_versions() const { return _previous_versions; }
 712 #else
 713   InstanceKlass* previous_versions() const { return nullptr; }
 714 #endif
 715 
 716   const InstanceKlass* get_klass_version(int version) const;
 717 
 718   bool has_been_redefined() const { return _misc_flags.has_been_redefined(); }
 719   void set_has_been_redefined() { _misc_flags.set_has_been_redefined(true); }
 720 
 721   bool is_scratch_class() const { return _misc_flags.is_scratch_class(); }
 722   void set_is_scratch_class() { _misc_flags.set_is_scratch_class(true); }
 723 
 724   bool has_resolved_methods() const { return _misc_flags.has_resolved_methods(); }
 725   void set_has_resolved_methods()   { _misc_flags.set_has_resolved_methods(true); }
 726   void set_has_resolved_methods(bool value)   { _misc_flags.set_has_resolved_methods(value); }
 727 
 728 public:
 729 #if INCLUDE_JVMTI
 730 
 731   void init_previous_versions() {
 732     _previous_versions = nullptr;
 733   }
 734 
 735  private:
 736   static bool  _should_clean_previous_versions;
 737  public:
 738   static void purge_previous_versions(InstanceKlass* ik) {
 739     if (ik->has_been_redefined()) {
 740       ik->purge_previous_version_list();
 741     }
 742   }
 743 
 744   static bool should_clean_previous_versions_and_reset();
 745   static bool should_clean_previous_versions() { return _should_clean_previous_versions; }
 746 
 747   // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
 748   void set_cached_class_file(JvmtiCachedClassFileData *data) {
 749     _cached_class_file = data;
 750   }
 751   JvmtiCachedClassFileData * get_cached_class_file();
 752   jint get_cached_class_file_len();
 753   unsigned char * get_cached_class_file_bytes();
 754 
 755   // JVMTI: Support for caching of field indices, types, and offsets
 756   void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
 757     _jvmti_cached_class_field_map = descriptor;
 758   }
 759   JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
 760     return _jvmti_cached_class_field_map;
 761   }
 762 #else // INCLUDE_JVMTI
 763 
 764   static void purge_previous_versions(InstanceKlass* ik) { return; };
 765   static bool should_clean_previous_versions_and_reset() { return false; }
 766 
 767   void set_cached_class_file(JvmtiCachedClassFileData *data) {
 768     assert(data == nullptr, "unexpected call with JVMTI disabled");
 769   }
 770   JvmtiCachedClassFileData * get_cached_class_file() { return (JvmtiCachedClassFileData *)nullptr; }
 771 
 772 #endif // INCLUDE_JVMTI
 773 
 774   bool has_nonstatic_concrete_methods() const { return _misc_flags.has_nonstatic_concrete_methods(); }
 775   void set_has_nonstatic_concrete_methods(bool b) { _misc_flags.set_has_nonstatic_concrete_methods(b); }
 776 
 777   bool declares_nonstatic_concrete_methods() const { return _misc_flags.declares_nonstatic_concrete_methods(); }
 778   void set_declares_nonstatic_concrete_methods(bool b) { _misc_flags.set_declares_nonstatic_concrete_methods(b); }
 779 
 780   bool has_miranda_methods () const     { return _misc_flags.has_miranda_methods(); }
 781   void set_has_miranda_methods()        { _misc_flags.set_has_miranda_methods(true); }
 782   bool has_final_method() const         { return _misc_flags.has_final_method(); }
 783   void set_has_final_method()           { _misc_flags.set_has_final_method(true); }
 784 
 785   // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
 786   inline u2 next_method_idnum();
 787   void set_initial_method_idnum(u2 value)             { _idnum_allocated_count = value; }
 788 
 789   // generics support
 790   Symbol* generic_signature() const;
 791   u2 generic_signature_index() const;
 792   void set_generic_signature_index(u2 sig_index);
 793 
 794   u2 enclosing_method_data(int offset) const;
 795   u2 enclosing_method_class_index() const {
 796     return enclosing_method_data(enclosing_method_class_index_offset);
 797   }
 798   u2 enclosing_method_method_index() {
 799     return enclosing_method_data(enclosing_method_method_index_offset);
 800   }
 801   void set_enclosing_method_indices(u2 class_index,
 802                                     u2 method_index);
 803 
 804   // jmethodID support
 805   jmethodID get_jmethod_id(Method* method);
 806   void make_methods_jmethod_ids();
 807   jmethodID jmethod_id_or_null(Method* method);
 808   void update_methods_jmethod_cache();
 809 
 810   // annotations support
 811   Annotations* annotations() const          { return _annotations; }
 812   void set_annotations(Annotations* anno)   { _annotations = anno; }
 813 
 814   AnnotationArray* class_annotations() const {
 815     return (_annotations != nullptr) ? _annotations->class_annotations() : nullptr;
 816   }
 817   Array<AnnotationArray*>* fields_annotations() const {
 818     return (_annotations != nullptr) ? _annotations->fields_annotations() : nullptr;
 819   }
 820   AnnotationArray* class_type_annotations() const {
 821     return (_annotations != nullptr) ? _annotations->class_type_annotations() : nullptr;
 822   }
 823   Array<AnnotationArray*>* fields_type_annotations() const {
 824     return (_annotations != nullptr) ? _annotations->fields_type_annotations() : nullptr;
 825   }
 826   // allocation
 827   instanceOop allocate_instance(TRAPS);
 828   static instanceOop allocate_instance(oop cls, TRAPS);
 829 
 830   // additional member function to return a handle
 831   instanceHandle allocate_instance_handle(TRAPS);
 832 
 833   // Helper function
 834   static instanceOop register_finalizer(instanceOop i, TRAPS);
 835 
 836   // Check whether reflection/jni/jvm code is allowed to instantiate this class;
 837   // if not, throw either an Error or an Exception.
 838   void check_valid_for_instantiation(bool throwError, TRAPS) override;
 839 
 840   // initialization
 841   void call_class_initializer(TRAPS);
 842   void set_initialization_state_and_notify(ClassState state, TRAPS);
 843 
 844   // OopMapCache support
 845   OopMapCache* oop_map_cache()               { return _oop_map_cache; }
 846   void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
 847   void mask_for(const methodHandle& method, int bci, InterpreterOopMap* entry);
 848 
 849   // JNI identifier support (for static fields - for jni performance)
 850   JNIid* jni_ids()                               { return _jni_ids; }
 851   void set_jni_ids(JNIid* ids)                   { _jni_ids = ids; }
 852   JNIid* jni_id_for(int offset);
 853 
 854  public:
 855   // maintenance of deoptimization dependencies
 856   inline DependencyContext dependencies();
 857   void mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes);
 858   void add_dependent_nmethod(nmethod* nm);
 859   void clean_dependency_context();
 860   // Setup link to hierarchy and deoptimize
 861   void add_to_hierarchy(JavaThread* current);
 862 
 863   // On-stack replacement support
 864   nmethod* osr_nmethods_head() const         { return _osr_nmethods_head; };
 865   void set_osr_nmethods_head(nmethod* h)     { _osr_nmethods_head = h; };
 866   void add_osr_nmethod(nmethod* n);
 867   bool remove_osr_nmethod(nmethod* n);
 868   int mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m);
 869   nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
 870 
 871 #if INCLUDE_JVMTI
 872   // Breakpoint support (see methods on Method* for details)
 873   BreakpointInfo* breakpoints() const       { return _breakpoints; };
 874   void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
 875 #endif
 876 
 877   // support for stub routines
 878   static ByteSize init_state_offset()  { return byte_offset_of(InstanceKlass, _init_state); }
 879   JFR_ONLY(DEFINE_KLASS_TRACE_ID_OFFSET;)
 880   static ByteSize init_thread_offset() { return byte_offset_of(InstanceKlass, _init_thread); }
 881 
 882   // subclass/subinterface checks
 883   bool implements_interface(Klass* k) const;
 884   bool is_same_or_direct_interface(Klass* k) const;
 885 
 886 #ifdef ASSERT
 887   // check whether this class or one of its superclasses was redefined
 888   bool has_redefined_this_or_super() const;
 889 #endif
 890 
 891   // Access to the implementor of an interface.
 892   InstanceKlass* implementor() const;
 893   void set_implementor(InstanceKlass* ik);
 894   int  nof_implementors() const;
 895   void add_implementor(InstanceKlass* ik);  // ik is a new class that implements this interface
 896   void init_implementor();           // initialize
 897 
 898  private:
 899   // link this class into the implementors list of every interface it implements
 900   void process_interfaces();
 901 
 902  public:
 903   // virtual operations from Klass
 904   GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
 905                                                   Array<InstanceKlass*>* transitive_interfaces) override;
 906   bool can_be_primary_super_slow() const override;
 907   size_t oop_size(oop obj, markWord mark) const override { return size_helper(); }
 908   // slow because it's a virtual call and used for verifying the layout_helper.
 909   // Using the layout_helper bits, we can call is_instance_klass without a virtual call.
 910   DEBUG_ONLY(bool is_instance_klass_slow() const override { return true; })
 911 
 912   // Iterators
 913   void do_local_static_fields(FieldClosure* cl);
 914   void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
 915   void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
 916   void print_nonstatic_fields(FieldClosure* cl); // including inherited and injected fields
 917 
 918   void methods_do(void f(Method* method));
 919 
 920   static InstanceKlass* cast(Klass* k) {
 921     return const_cast<InstanceKlass*>(cast(const_cast<const Klass*>(k)));
 922   }
 923 
 924   static const InstanceKlass* cast(const Klass* k) {
 925     assert(k != nullptr, "k should not be null");
 926     assert(k->is_instance_klass(), "cast to InstanceKlass");
 927     return static_cast<const InstanceKlass*>(k);
 928   }
 929 
 930   // This hides Klass::super(). The _super of an InstanceKlass is
 931   // always an InstanceKlass (or nullptr)
 932   InstanceKlass* super() const {
 933     return (Klass::super() == nullptr) ? nullptr : InstanceKlass::cast(Klass::super());
 934   }
 935 
 936   InstanceKlass* java_super() const override {
 937     return InstanceKlass::super();
 938   }
 939 
 940   // Sizing (in words)
 941   static int header_size()            { return sizeof(InstanceKlass)/wordSize; }
 942 
 943   static int size(int vtable_length, int itable_length,
 944                   int nonstatic_oop_map_size,
 945                   bool is_interface) {
 946     return align_metadata_size(header_size() +
 947            vtable_length +
 948            itable_length +
 949            nonstatic_oop_map_size +
 950            (is_interface ? (int)sizeof(Klass*)/wordSize : 0));
 951   }
 952 
 953   int size() const override           { return size(vtable_length(),
 954                                                     itable_length(),
 955                                                     nonstatic_oop_map_size(),
 956                                                     is_interface());
 957   }
 958 
 959 
 960   inline intptr_t* start_of_itable() const;
 961   inline intptr_t* end_of_itable() const;
 962   inline oop static_field_base_raw();
 963 
 964   inline OopMapBlock* start_of_nonstatic_oop_maps() const;
 965   inline Klass** end_of_nonstatic_oop_maps() const;
 966 
 967   inline InstanceKlass* volatile* adr_implementor() const;
 968 
 969   // Use this to return the size of an instance in heap words:
 970   int size_helper() const {
 971     return layout_helper_to_size_helper(layout_helper());
 972   }
 973 
 974   virtual int hash_offset_in_bytes(oop obj, markWord m) const override {
 975     assert(UseCompactObjectHeaders, "only with compact i-hash");
 976     return _hash_offset;
 977   }
 978   static int hash_offset_offset_in_bytes() {
 979     assert(UseCompactObjectHeaders, "only with compact i-hash");
 980     return (int)offset_of(InstanceKlass, _hash_offset);
 981   }
 982 
 983   // This bit is initialized in classFileParser.cpp.
 984   // It is false under any of the following conditions:
 985   //  - the class is abstract (including any interface)
 986   //  - the class size is larger than FastAllocateSizeLimit
 987   //  - the class is java/lang/Class, which cannot be allocated directly
 988   bool can_be_fastpath_allocated() const {
 989     return !layout_helper_needs_slow_path(layout_helper());
 990   }
 991 
 992   // Java itable
 993   klassItable itable() const;        // return klassItable wrapper
 994   Method* method_at_itable(InstanceKlass* holder, int index, TRAPS);
 995   Method* method_at_itable_or_null(InstanceKlass* holder, int index, bool& itable_entry_found);
 996   int vtable_index_of_interface_method(Method* method);
 997 
 998 #if INCLUDE_JVMTI
 999   void adjust_default_methods(bool* trace_name_printed);
1000 #endif // INCLUDE_JVMTI
1001 
1002   void clean_weak_instanceklass_links();
1003  private:
1004   void clean_implementors_list();
1005   void clean_method_data();
1006 
1007  public:
1008   // Explicit metaspace deallocation of fields
1009   // For RedefineClasses and class file parsing errors, we need to deallocate
1010   // instanceKlasses and the metadata they point to.
1011   void deallocate_contents(ClassLoaderData* loader_data);
1012   static void deallocate_methods(ClassLoaderData* loader_data,
1013                                  Array<Method*>* methods);
1014   void static deallocate_interfaces(ClassLoaderData* loader_data,
1015                                     const InstanceKlass* super_klass,
1016                                     Array<InstanceKlass*>* local_interfaces,
1017                                     Array<InstanceKlass*>* transitive_interfaces);
1018   void static deallocate_record_components(ClassLoaderData* loader_data,
1019                                            Array<RecordComponent*>* record_component);
1020 
1021   bool on_stack() const override;
1022 
1023   // callbacks for actions during class unloading
1024   static void unload_class(InstanceKlass* ik);
1025 
1026   void release_C_heap_structures(bool release_sub_metadata = true) override;
1027 
1028   // Naming
1029   const char* signature_name() const override;
1030 
1031   // Oop fields (and metadata) iterators
1032   //
1033   // The InstanceKlass iterators also visits the Object's klass.
1034 
1035   // Forward iteration
1036  public:
1037   // Iterate over all oop fields in the oop maps.
1038   template <typename T, class OopClosureType>
1039   inline void oop_oop_iterate_oop_maps(oop obj, OopClosureType* closure);
1040 
1041   // Iterate over all oop fields and metadata.
1042   template <typename T, class OopClosureType>
1043   inline void oop_oop_iterate(oop obj, OopClosureType* closure);
1044 
1045   // Iterate over all oop fields in one oop map.
1046   template <typename T, class OopClosureType>
1047   inline void oop_oop_iterate_oop_map(OopMapBlock* map, oop obj, OopClosureType* closure);
1048 
1049 
1050   // Reverse iteration
1051   // Iterate over all oop fields and metadata.
1052   template <typename T, class OopClosureType>
1053   inline void oop_oop_iterate_reverse(oop obj, OopClosureType* closure);
1054 
1055  private:
1056   // Iterate over all oop fields in the oop maps.
1057   template <typename T, class OopClosureType>
1058   inline void oop_oop_iterate_oop_maps_reverse(oop obj, OopClosureType* closure);
1059 
1060   // Iterate over all oop fields in one oop map.
1061   template <typename T, class OopClosureType>
1062   inline void oop_oop_iterate_oop_map_reverse(OopMapBlock* map, oop obj, OopClosureType* closure);
1063 
1064 
1065   // Bounded range iteration
1066  public:
1067   // Iterate over all oop fields in the oop maps.
1068   template <typename T, class OopClosureType>
1069   inline void oop_oop_iterate_oop_maps_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1070 
1071   // Iterate over all oop fields and metadata.
1072   template <typename T, class OopClosureType>
1073   inline void oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1074 
1075  private:
1076   // Iterate over all oop fields in one oop map.
1077   template <typename T, class OopClosureType>
1078   inline void oop_oop_iterate_oop_map_bounded(OopMapBlock* map, oop obj, OopClosureType* closure, MemRegion mr);
1079 
1080 
1081  public:
1082   u2 idnum_allocated_count() const      { return _idnum_allocated_count; }
1083 
1084 private:
1085   // initialization state
1086   void set_init_state(ClassState state);
1087   void set_rewritten()                  { _misc_flags.set_rewritten(true); }
1088   void set_init_thread(JavaThread *thread)  {
1089     assert((thread == JavaThread::current() && _init_thread == nullptr) ||
1090            (thread == nullptr && _init_thread == JavaThread::current()), "Only one thread is allowed to own initialization");
1091     AtomicAccess::store(&_init_thread, thread);
1092   }
1093 
1094   jmethodID* methods_jmethod_ids_acquire() const;
1095   void release_set_methods_jmethod_ids(jmethodID* jmeths);
1096   // This nulls out obsolete jmethodIDs for all methods in 'klass'.
1097   static void clear_obsolete_jmethod_ids(InstanceKlass* klass);
1098   jmethodID update_jmethod_id(jmethodID* jmeths, Method* method, int idnum);
1099 
1100 public:
1101   // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1102   // Must be one per class and it has to be a VM internal object so java code
1103   // cannot lock it (like the mirror).
1104   // It has to be an object not a Mutex because it's held through java calls.
1105   oop init_lock() const;
1106 
1107   // Returns the array class for the n'th dimension
1108   ArrayKlass* array_klass(int n, TRAPS) override;
1109   ArrayKlass* array_klass_or_null(int n) override;
1110 
1111   // Returns the array class with this class as element type
1112   ArrayKlass* array_klass(TRAPS) override;
1113   ArrayKlass* array_klass_or_null() override;
1114 
1115   static void clean_initialization_error_table();
1116 private:
1117   void fence_and_clear_init_lock();
1118 
1119   bool link_class_impl                           (TRAPS);
1120   bool verify_code                               (TRAPS);
1121   void initialize_impl                           (TRAPS);
1122   void initialize_super_interfaces               (TRAPS);
1123 
1124   void add_initialization_error(JavaThread* current, Handle exception);
1125   oop get_initialization_error(JavaThread* current);
1126 
1127   // find a local method (returns null if not found)
1128   Method* find_method_impl(const Symbol* name,
1129                            const Symbol* signature,
1130                            OverpassLookupMode overpass_mode,
1131                            StaticLookupMode static_mode,
1132                            PrivateLookupMode private_mode) const;
1133 
1134   static Method* find_method_impl(const Array<Method*>* methods,
1135                                   const Symbol* name,
1136                                   const Symbol* signature,
1137                                   OverpassLookupMode overpass_mode,
1138                                   StaticLookupMode static_mode,
1139                                   PrivateLookupMode private_mode);
1140 
1141 #if INCLUDE_JVMTI
1142   // RedefineClasses support
1143   void link_previous_versions(InstanceKlass* pv) { _previous_versions = pv; }
1144   void mark_newly_obsolete_methods(Array<Method*>* old_methods, int emcp_method_count);
1145 #endif
1146 public:
1147 
1148 #if INCLUDE_CDS
1149   // CDS support - remove and restore oops from metadata. Oops are not shared.
1150   void remove_unshareable_info() override;
1151   void remove_unshareable_flags();
1152   void remove_java_mirror() override;
1153   void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, PackageEntry* pkg_entry, TRAPS);
1154   void init_shared_package_entry();
1155   bool can_be_verified_at_dumptime() const;
1156   void compute_has_loops_flag_for_methods();
1157 #endif
1158   bool     has_init_deps_processed() const { return _misc_flags.has_init_deps_processed(); }
1159   void set_has_init_deps_processed() {
1160     assert(is_initialized(), "");
1161     assert(!has_init_deps_processed(), "already set"); // one-off action
1162     _misc_flags.set_has_init_deps_processed(true);
1163   }
1164 
1165   u2 compute_modifier_flags() const override;
1166 
1167 public:
1168   // JVMTI support
1169   jint jvmti_class_status() const override;
1170 
1171   void metaspace_pointers_do(MetaspaceClosure* iter) override;
1172 
1173  public:
1174   // Printing
1175   void print_on(outputStream* st) const override;
1176   void print_value_on(outputStream* st) const override;
1177   void print_class_flags(outputStream* st) const;
1178 
1179   void oop_print_value_on(oop obj, outputStream* st) override;
1180 
1181   void oop_print_on      (oop obj, outputStream* st) override;
1182 
1183 #ifndef PRODUCT
1184   void print_dependent_nmethods(bool verbose = false);
1185   bool is_dependent_nmethod(nmethod* nm);
1186   bool verify_itable_index(int index);
1187 #endif
1188 
1189   const char* internal_name() const override;
1190 
1191   // Verification
1192   void verify_on(outputStream* st) override;
1193 
1194   void oop_verify_on(oop obj, outputStream* st) override;
1195 
1196   // Logging
1197   void print_class_load_logging(ClassLoaderData* loader_data,
1198                                 const ModuleEntry* module_entry,
1199                                 const ClassFileStream* cfs) const;
1200  private:
1201   void print_class_load_cause_logging() const;
1202   void print_class_load_helper(ClassLoaderData* loader_data,
1203                                const ModuleEntry* module_entry,
1204                                const ClassFileStream* cfs) const;
1205 };
1206 
1207 // for adding methods
1208 // UNSET_IDNUM return means no more ids available
1209 inline u2 InstanceKlass::next_method_idnum() {
1210   if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1211     return ConstMethod::UNSET_IDNUM; // no more ids available
1212   } else {
1213     return _idnum_allocated_count++;
1214   }
1215 }
1216 
1217 class PrintClassClosure : public KlassClosure {
1218 private:
1219   outputStream* _st;
1220   bool _verbose;
1221 public:
1222   PrintClassClosure(outputStream* st, bool verbose);
1223 
1224   void do_klass(Klass* k);
1225 };
1226 
1227 /* JNIid class for jfieldIDs only */
1228 class JNIid: public CHeapObj<mtClass> {
1229   friend class VMStructs;
1230  private:
1231   InstanceKlass*     _holder;
1232   JNIid*             _next;
1233   int                _offset;
1234 #ifdef ASSERT
1235   bool               _is_static_field_id;
1236 #endif
1237 
1238  public:
1239   // Accessors
1240   InstanceKlass* holder() const   { return _holder; }
1241   int offset() const              { return _offset; }
1242   JNIid* next()                   { return _next; }
1243   // Constructor
1244   JNIid(InstanceKlass* holder, int offset, JNIid* next);
1245   // Identifier lookup
1246   JNIid* find(int offset);
1247 
1248   bool find_local_field(fieldDescriptor* fd) {
1249     return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1250   }
1251 
1252   static void deallocate(JNIid* id);
1253   // Debugging
1254 #ifdef ASSERT
1255   bool is_static_field_id() const { return _is_static_field_id; }
1256   void set_is_static_field_id()   { _is_static_field_id = true; }
1257 #endif
1258   void verify(InstanceKlass* holder);
1259 };
1260 
1261 // An iterator that's used to access the inner classes indices in the
1262 // InstanceKlass::_inner_classes array.
1263 class InnerClassesIterator : public StackObj {
1264  private:
1265   Array<jushort>* _inner_classes;
1266   int _length;
1267   int _idx;
1268  public:
1269 
1270   InnerClassesIterator(const InstanceKlass* k) {
1271     _inner_classes = k->inner_classes();
1272     if (k->inner_classes() != nullptr) {
1273       _length = _inner_classes->length();
1274       // The inner class array's length should be the multiple of
1275       // inner_class_next_offset if it only contains the InnerClasses
1276       // attribute data, or it should be
1277       // n*inner_class_next_offset+enclosing_method_attribute_size
1278       // if it also contains the EnclosingMethod data.
1279       assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1280               _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1281              "just checking");
1282       // Remove the enclosing_method portion if exists.
1283       if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1284         _length -= InstanceKlass::enclosing_method_attribute_size;
1285       }
1286     } else {
1287       _length = 0;
1288     }
1289     _idx = 0;
1290   }
1291 
1292   int length() const {
1293     return _length;
1294   }
1295 
1296   void next() {
1297     _idx += InstanceKlass::inner_class_next_offset;
1298   }
1299 
1300   bool done() const {
1301     return (_idx >= _length);
1302   }
1303 
1304   u2 inner_class_info_index() const {
1305     return _inner_classes->at(
1306                _idx + InstanceKlass::inner_class_inner_class_info_offset);
1307   }
1308 
1309   void set_inner_class_info_index(u2 index) {
1310     _inner_classes->at_put(
1311                _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1312   }
1313 
1314   u2 outer_class_info_index() const {
1315     return _inner_classes->at(
1316                _idx + InstanceKlass::inner_class_outer_class_info_offset);
1317   }
1318 
1319   void set_outer_class_info_index(u2 index) {
1320     _inner_classes->at_put(
1321                _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1322   }
1323 
1324   u2 inner_name_index() const {
1325     return _inner_classes->at(
1326                _idx + InstanceKlass::inner_class_inner_name_offset);
1327   }
1328 
1329   void set_inner_name_index(u2 index) {
1330     _inner_classes->at_put(
1331                _idx + InstanceKlass::inner_class_inner_name_offset, index);
1332   }
1333 
1334   u2 inner_access_flags() const {
1335     return _inner_classes->at(
1336                _idx + InstanceKlass::inner_class_access_flags_offset);
1337   }
1338 };
1339 
1340 // Iterator over class hierarchy under a particular class. Implements depth-first pre-order traversal.
1341 // Usage:
1342 //  for (ClassHierarchyIterator iter(root_klass); !iter.done(); iter.next()) {
1343 //    Klass* k = iter.klass();
1344 //    ...
1345 //  }
1346 class ClassHierarchyIterator : public StackObj {
1347  private:
1348   InstanceKlass* _root;
1349   Klass*         _current;
1350   bool           _visit_subclasses;
1351 
1352  public:
1353   ClassHierarchyIterator(InstanceKlass* root) : _root(root), _current(root), _visit_subclasses(true) {
1354     assert(_root == _current, "required"); // initial state
1355   }
1356 
1357   bool done() {
1358     return (_current == nullptr);
1359   }
1360 
1361   // Make a step iterating over the class hierarchy under the root class.
1362   // Skips subclasses if requested.
1363   void next();
1364 
1365   Klass* klass() {
1366     assert(!done(), "sanity");
1367     return _current;
1368   }
1369 
1370   // Skip subclasses of the current class.
1371   void skip_subclasses() {
1372     _visit_subclasses = false;
1373   }
1374 };
1375 
1376 #endif // SHARE_OOPS_INSTANCEKLASS_HPP