1 /*
   2  * Copyright (c) 1997, 2024, 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/referenceType.hpp"
  29 #include "oops/annotations.hpp"
  30 #include "oops/constMethod.hpp"
  31 #include "oops/fieldInfo.hpp"
  32 #include "oops/instanceKlassFlags.hpp"
  33 #include "oops/instanceOop.hpp"
  34 #include "runtime/handles.hpp"
  35 #include "runtime/javaThread.hpp"
  36 #include "utilities/accessFlags.hpp"
  37 #include "utilities/align.hpp"
  38 #include "utilities/growableArray.hpp"
  39 #include "utilities/macros.hpp"
  40 #if INCLUDE_JFR
  41 #include "jfr/support/jfrKlassExtension.hpp"
  42 #endif
  43 
  44 class ConstantPool;
  45 class DeoptimizationScope;
  46 class klassItable;
  47 class Monitor;
  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 jniIdMapBase;
  71 class JNIid;
  72 class JvmtiCachedClassFieldMap;
  73 class nmethodBucket;
  74 class OopMapCache;
  75 class InterpreterOopMap;
  76 class PackageEntry;
  77 class ModuleEntry;
  78 
  79 // This is used in iterators below.
  80 class FieldClosure: public StackObj {
  81 public:
  82   virtual void do_field(fieldDescriptor* fd) = 0;
  83 };
  84 
  85 // Print fields.
  86 // If "obj" argument to constructor is null, prints static fields, otherwise prints non-static fields.
  87 class FieldPrinter: public FieldClosure {
  88    oop _obj;
  89    outputStream* _st;
  90  public:
  91    FieldPrinter(outputStream* st, oop obj = nullptr) : _obj(obj), _st(st) {}
  92    void do_field(fieldDescriptor* fd);
  93 };
  94 
  95 // Describes where oops are located in instances of this klass.
  96 class OopMapBlock {
  97  public:
  98   // Byte offset of the first oop mapped by this block.
  99   int offset() const          { return _offset; }
 100   void set_offset(int offset) { _offset = offset; }
 101 
 102   // Number of oops in this block.
 103   uint count() const         { return _count; }
 104   void set_count(uint count) { _count = count; }
 105 
 106   void increment_count(int diff) { _count += diff; }
 107 
 108   int offset_span() const { return _count * heapOopSize; }
 109 
 110   int end_offset() const {
 111     return offset() + offset_span();
 112   }
 113 
 114   bool is_contiguous(int another_offset) const {
 115     return another_offset == end_offset();
 116   }
 117 
 118   // sizeof(OopMapBlock) in words.
 119   static int size_in_words() {
 120     return align_up((int)sizeof(OopMapBlock), wordSize) >>
 121       LogBytesPerWord;
 122   }
 123 
 124   static int compare_offset(const OopMapBlock* a, const OopMapBlock* b) {
 125     return a->offset() - b->offset();
 126   }
 127 
 128  private:
 129   int  _offset;
 130   uint _count;
 131 };
 132 
 133 struct JvmtiCachedClassFileData;
 134 
 135 class InstanceKlass: public Klass {
 136   friend class VMStructs;
 137   friend class JVMCIVMStructs;
 138   friend class ClassFileParser;
 139   friend class CompileReplay;
 140 
 141  public:
 142   static const KlassKind Kind = InstanceKlassKind;
 143 
 144  protected:
 145   InstanceKlass(const ClassFileParser& parser, KlassKind kind = Kind, ReferenceType reference_type = REF_NONE);
 146 
 147  public:
 148   InstanceKlass();
 149 
 150   // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
 151   // of the class loading & initialization procedure, and the use of the states.
 152   enum ClassState : u1 {
 153     allocated,                          // allocated (but not yet linked)
 154     loaded,                             // loaded and inserted in class hierarchy (but not linked yet)
 155     being_linked,                       // currently running verifier and rewriter
 156     linked,                             // successfully linked/verified (but not initialized yet)
 157     being_initialized,                  // currently running class initializer
 158     fully_initialized,                  // initialized (successful final state)
 159     initialization_error                // error happened during initialization
 160   };
 161 
 162  private:
 163   static InstanceKlass* allocate_instance_klass(const ClassFileParser& parser, TRAPS);
 164 
 165  protected:
 166   // If you add a new field that points to any metaspace object, you
 167   // must add this field to InstanceKlass::metaspace_pointers_do().
 168 
 169   // Annotations for this class
 170   Annotations*    _annotations;
 171   // Package this class is defined in
 172   PackageEntry*   _package_entry;
 173   // Array classes holding elements of this class.
 174   ObjArrayKlass* volatile _array_klasses;
 175   // Constant pool for this class.
 176   ConstantPool* _constants;
 177   // The InnerClasses attribute and EnclosingMethod attribute. The
 178   // _inner_classes is an array of shorts. If the class has InnerClasses
 179   // attribute, then the _inner_classes array begins with 4-tuples of shorts
 180   // [inner_class_info_index, outer_class_info_index,
 181   // inner_name_index, inner_class_access_flags] for the InnerClasses
 182   // attribute. If the EnclosingMethod attribute exists, it occupies the
 183   // last two shorts [class_index, method_index] of the array. If only
 184   // the InnerClasses attribute exists, the _inner_classes array length is
 185   // number_of_inner_classes * 4. If the class has both InnerClasses
 186   // and EnclosingMethod attributes the _inner_classes array length is
 187   // number_of_inner_classes * 4 + enclosing_method_attribute_size.
 188   Array<jushort>* _inner_classes;
 189 
 190   // The NestMembers attribute. An array of shorts, where each is a
 191   // class info index for the class that is a nest member. This data
 192   // has not been validated.
 193   Array<jushort>* _nest_members;
 194 
 195   // Resolved nest-host klass: either true nest-host or self if we are not
 196   // nested, or an error occurred resolving or validating the nominated
 197   // nest-host. Can also be set directly by JDK API's that establish nest
 198   // relationships.
 199   // By always being set it makes nest-member access checks simpler.
 200   InstanceKlass* _nest_host;
 201 
 202   // The PermittedSubclasses attribute. An array of shorts, where each is a
 203   // class info index for the class that is a permitted subclass.
 204   Array<jushort>* _permitted_subclasses;
 205 
 206   // The contents of the Record attribute.
 207   Array<RecordComponent*>* _record_components;
 208 
 209   // the source debug extension for this klass, null if not specified.
 210   // Specified as UTF-8 string without terminating zero byte in the classfile,
 211   // it is stored in the instanceklass as a null-terminated UTF-8 string
 212   const char*     _source_debug_extension;
 213 
 214   // Number of heapOopSize words used by non-static fields in this klass
 215   // (including inherited fields but after header_size()).
 216   int             _nonstatic_field_size;
 217   int             _static_field_size;       // number words used by static fields (oop and non-oop) in this klass
 218   int             _nonstatic_oop_map_size;  // size in words of nonstatic oop map blocks
 219   int             _itable_len;              // length of Java itable (in words)
 220 
 221   // The NestHost attribute. The class info index for the class
 222   // that is the nest-host of this class. This data has not been validated.
 223   u2              _nest_host_index;
 224   u2              _this_class_index;        // constant pool entry
 225   u2              _static_oop_field_count;  // number of static oop fields in this klass
 226 
 227   volatile u2     _idnum_allocated_count;   // JNI/JVMTI: increments with the addition of methods, old ids don't change
 228 
 229   volatile ClassState _init_state;          // state of class
 230 
 231   u1              _reference_type;          // reference type
 232 
 233   // State is set either at parse time or while executing, atomically to not disturb other state
 234   InstanceKlassFlags _misc_flags;
 235 
 236   Monitor*             _init_monitor;       // mutual exclusion to _init_state and _init_thread.
 237   JavaThread* volatile _init_thread;        // Pointer to current thread doing initialization (to handle recursive initialization)
 238 
 239   OopMapCache*    volatile _oop_map_cache;   // OopMapCache for all methods in the klass (allocated lazily)
 240   JNIid*          _jni_ids;                  // First JNI identifier for static fields in this class
 241   jmethodID* volatile _methods_jmethod_ids;  // jmethodIDs corresponding to method_idnum, or null if none
 242   nmethodBucket*  volatile _dep_context;     // packed DependencyContext structure
 243   uint64_t        volatile _dep_context_last_cleaned;
 244   nmethod*        _osr_nmethods_head;    // Head of list of on-stack replacement nmethods for this class
 245 #if INCLUDE_JVMTI
 246   BreakpointInfo* _breakpoints;          // bpt lists, managed by Method*
 247   // Linked instanceKlasses of previous versions
 248   InstanceKlass* _previous_versions;
 249   // JVMTI fields can be moved to their own structure - see 6315920
 250   // JVMTI: cached class file, before retransformable agent modified it in CFLH
 251   JvmtiCachedClassFileData* _cached_class_file;
 252 #endif
 253 
 254 #if INCLUDE_JVMTI
 255   JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map;  // JVMTI: used during heap iteration
 256 #endif
 257 
 258   NOT_PRODUCT(int _verify_count;)  // to avoid redundant verifies
 259   NOT_PRODUCT(volatile int _shared_class_load_count;) // ensure a shared class is loaded only once
 260 
 261   // Method array.
 262   Array<Method*>* _methods;
 263   // Default Method Array, concrete methods inherited from interfaces
 264   Array<Method*>* _default_methods;
 265   // Interfaces (InstanceKlass*s) this class declares locally to implement.
 266   Array<InstanceKlass*>* _local_interfaces;
 267   // Interfaces (InstanceKlass*s) this class implements transitively.
 268   Array<InstanceKlass*>* _transitive_interfaces;
 269   // Int array containing the original order of method in the class file (for JVMTI).
 270   Array<int>*     _method_ordering;
 271   // Int array containing the vtable_indices for default_methods
 272   // offset matches _default_methods offset
 273   Array<int>*     _default_vtable_indices;
 274 
 275   // Fields information is stored in an UNSIGNED5 encoded stream (see fieldInfo.hpp)
 276   Array<u1>*          _fieldinfo_stream;
 277   Array<FieldStatus>* _fields_status;
 278 
 279   // embedded Java vtable follows here
 280   // embedded Java itables follows here
 281   // embedded static fields follows here
 282   // embedded nonstatic oop-map blocks follows here
 283   // embedded implementor of this interface follows here
 284   //   The embedded implementor only exists if the current klass is an
 285   //   interface. The possible values of the implementor fall into following
 286   //   three cases:
 287   //     null: no implementor.
 288   //     A Klass* that's not itself: one implementor.
 289   //     Itself: more than one implementors.
 290   //
 291 
 292   friend class SystemDictionary;
 293 
 294   static bool _disable_method_binary_search;
 295 
 296   // Controls finalizer registration
 297   static bool _finalization_enabled;
 298 
 299  public:
 300 
 301   // Queries finalization state
 302   static bool is_finalization_enabled() { return _finalization_enabled; }
 303 
 304   // Sets finalization state
 305   static void set_finalization_enabled(bool val) { _finalization_enabled = val; }
 306 
 307   // The three BUILTIN class loader types
 308   bool is_shared_boot_class() const { return _misc_flags.is_shared_boot_class(); }
 309   bool is_shared_platform_class() const { return _misc_flags.is_shared_platform_class(); }
 310   bool is_shared_app_class() const {  return _misc_flags.is_shared_app_class(); }
 311   // The UNREGISTERED class loader type
 312   bool is_shared_unregistered_class() const { return _misc_flags.is_shared_unregistered_class(); }
 313 
 314   // Check if the class can be shared in CDS
 315   bool is_shareable() const;
 316 
 317   bool shared_loading_failed() const { return _misc_flags.shared_loading_failed(); }
 318 
 319   void set_shared_loading_failed() { _misc_flags.set_shared_loading_failed(true); }
 320 
 321 #if INCLUDE_CDS
 322   int  shared_class_loader_type() const;
 323   void set_shared_class_loader_type(s2 loader_type) { _misc_flags.set_shared_class_loader_type(loader_type); }
 324   void assign_class_loader_type() { _misc_flags.assign_class_loader_type(_class_loader_data); }
 325 #endif
 326 
 327   bool has_nonstatic_fields() const        { return _misc_flags.has_nonstatic_fields(); }
 328   void set_has_nonstatic_fields(bool b)    { _misc_flags.set_has_nonstatic_fields(b); }
 329 
 330   bool has_localvariable_table() const     { return _misc_flags.has_localvariable_table(); }
 331   void set_has_localvariable_table(bool b) { _misc_flags.set_has_localvariable_table(b); }
 332 
 333   // field sizes
 334   int nonstatic_field_size() const         { return _nonstatic_field_size; }
 335   void set_nonstatic_field_size(int size)  { _nonstatic_field_size = size; }
 336 
 337   int static_field_size() const            { return _static_field_size; }
 338   void set_static_field_size(int size)     { _static_field_size = size; }
 339 
 340   int static_oop_field_count() const       { return (int)_static_oop_field_count; }
 341   void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
 342 
 343   // Java itable
 344   int  itable_length() const               { return _itable_len; }
 345   void set_itable_length(int len)          { _itable_len = len; }
 346 
 347   // array klasses
 348   ObjArrayKlass* array_klasses() const     { return _array_klasses; }
 349   inline ObjArrayKlass* array_klasses_acquire() const; // load with acquire semantics
 350   inline void release_set_array_klasses(ObjArrayKlass* k); // store with release semantics
 351   void set_array_klasses(ObjArrayKlass* k) { _array_klasses = k; }
 352 
 353   // methods
 354   Array<Method*>* methods() const          { return _methods; }
 355   void set_methods(Array<Method*>* a)      { _methods = a; }
 356   Method* method_with_idnum(int idnum);
 357   Method* method_with_orig_idnum(int idnum);
 358   Method* method_with_orig_idnum(int idnum, int version);
 359 
 360   // method ordering
 361   Array<int>* method_ordering() const     { return _method_ordering; }
 362   void set_method_ordering(Array<int>* m) { _method_ordering = m; }
 363   void copy_method_ordering(const intArray* m, TRAPS);
 364 
 365   // default_methods
 366   Array<Method*>* default_methods() const  { return _default_methods; }
 367   void set_default_methods(Array<Method*>* a) { _default_methods = a; }
 368 
 369   // default method vtable_indices
 370   Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
 371   void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
 372   Array<int>* create_new_default_vtable_indices(int len, TRAPS);
 373 
 374   // interfaces
 375   Array<InstanceKlass*>* local_interfaces() const          { return _local_interfaces; }
 376   void set_local_interfaces(Array<InstanceKlass*>* a)      {
 377     guarantee(_local_interfaces == nullptr || a == nullptr, "Just checking");
 378     _local_interfaces = a; }
 379 
 380   Array<InstanceKlass*>* transitive_interfaces() const     { return _transitive_interfaces; }
 381   void set_transitive_interfaces(Array<InstanceKlass*>* a) {
 382     guarantee(_transitive_interfaces == nullptr || a == nullptr, "Just checking");
 383     _transitive_interfaces = a;
 384   }
 385 
 386  private:
 387   friend class fieldDescriptor;
 388   FieldInfo field(int index) const;
 389 
 390  public:
 391   int     field_offset      (int index) const { return field(index).offset(); }
 392   int     field_access_flags(int index) const { return field(index).access_flags().as_int(); }
 393   FieldInfo::FieldFlags field_flags(int index) const { return field(index).field_flags(); }
 394   FieldStatus field_status(int index)   const { return fields_status()->at(index); }
 395   inline Symbol* field_name        (int index) const;
 396   inline Symbol* field_signature   (int index) const;
 397 
 398   // Number of Java declared fields
 399   int java_fields_count() const;
 400   int total_fields_count() const;
 401 
 402   Array<u1>* fieldinfo_stream() const { return _fieldinfo_stream; }
 403   void set_fieldinfo_stream(Array<u1>* fis) { _fieldinfo_stream = fis; }
 404 
 405   Array<FieldStatus>* fields_status() const {return _fields_status; }
 406   void set_fields_status(Array<FieldStatus>* array) { _fields_status = array; }
 407 
 408   // inner classes
 409   Array<u2>* inner_classes() const       { return _inner_classes; }
 410   void set_inner_classes(Array<u2>* f)   { _inner_classes = f; }
 411 
 412   // nest members
 413   Array<u2>* nest_members() const     { return _nest_members; }
 414   void set_nest_members(Array<u2>* m) { _nest_members = m; }
 415 
 416   // nest-host index
 417   jushort nest_host_index() const { return _nest_host_index; }
 418   void set_nest_host_index(u2 i)  { _nest_host_index = i; }
 419   // dynamic nest member support
 420   void set_nest_host(InstanceKlass* host);
 421 
 422   // record components
 423   Array<RecordComponent*>* record_components() const { return _record_components; }
 424   void set_record_components(Array<RecordComponent*>* record_components) {
 425     _record_components = record_components;
 426   }
 427   bool is_record() const;
 428 
 429   // permitted subclasses
 430   Array<u2>* permitted_subclasses() const     { return _permitted_subclasses; }
 431   void set_permitted_subclasses(Array<u2>* s) { _permitted_subclasses = s; }
 432 
 433 private:
 434   // Called to verify that k is a member of this nest - does not look at k's nest-host,
 435   // nor does it resolve any CP entries or load any classes.
 436   bool has_nest_member(JavaThread* current, InstanceKlass* k) const;
 437 
 438 public:
 439   // Call this only if you know that the nest host has been initialized.
 440   InstanceKlass* nest_host_not_null() {
 441     assert(_nest_host != nullptr, "must be");
 442     return _nest_host;
 443   }
 444   // Used to construct informative IllegalAccessError messages at a higher level,
 445   // if there was an issue resolving or validating the nest host.
 446   // Returns null if there was no error.
 447   const char* nest_host_error();
 448   // Returns nest-host class, resolving and validating it if needed.
 449   // Returns null if resolution is not possible from the calling context.
 450   InstanceKlass* nest_host(TRAPS);
 451   // Check if this klass is a nestmate of k - resolves this nest-host and k's
 452   bool has_nestmate_access_to(InstanceKlass* k, TRAPS);
 453 
 454   // Called to verify that k is a permitted subclass of this class
 455   bool has_as_permitted_subclass(const InstanceKlass* k) const;
 456 
 457   enum InnerClassAttributeOffset {
 458     // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
 459     inner_class_inner_class_info_offset = 0,
 460     inner_class_outer_class_info_offset = 1,
 461     inner_class_inner_name_offset = 2,
 462     inner_class_access_flags_offset = 3,
 463     inner_class_next_offset = 4
 464   };
 465 
 466   enum EnclosingMethodAttributeOffset {
 467     enclosing_method_class_index_offset = 0,
 468     enclosing_method_method_index_offset = 1,
 469     enclosing_method_attribute_size = 2
 470   };
 471 
 472   // package
 473   PackageEntry* package() const     { return _package_entry; }
 474   ModuleEntry* module() const;
 475   bool in_unnamed_package() const   { return (_package_entry == nullptr); }
 476   void set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS);
 477   // If the package for the InstanceKlass is in the boot loader's package entry
 478   // table then sets the classpath_index field so that
 479   // get_system_package() will know to return a non-null value for the
 480   // package's location.  And, so that the package will be added to the list of
 481   // packages returned by get_system_packages().
 482   // For packages whose classes are loaded from the boot loader class path, the
 483   // classpath_index indicates which entry on the boot loader class path.
 484   void set_classpath_index(s2 path_index);
 485   bool is_same_class_package(const Klass* class2) const;
 486   bool is_same_class_package(oop other_class_loader, const Symbol* other_class_name) const;
 487 
 488   // find an enclosing class
 489   InstanceKlass* compute_enclosing_class(bool* inner_is_member, TRAPS) const;
 490 
 491   // Find InnerClasses attribute and return outer_class_info_index & inner_name_index.
 492   bool find_inner_classes_attr(int* ooff, int* noff, TRAPS) const;
 493 
 494  private:
 495   // Check prohibited package ("java/" only loadable by boot or platform loaders)
 496   static void check_prohibited_package(Symbol* class_name,
 497                                        ClassLoaderData* loader_data,
 498                                        TRAPS);
 499 
 500   JavaThread* init_thread()  { return Atomic::load(&_init_thread); }
 501   // We can safely access the name as long as we hold the _init_monitor.
 502   const char* init_thread_name() {
 503     assert(_init_monitor->owned_by_self(), "Must hold _init_monitor here");
 504     return init_thread()->name_raw();
 505   }
 506 
 507  public:
 508   // initialization state
 509   bool is_loaded() const                   { return init_state() >= loaded; }
 510   bool is_linked() const                   { return init_state() >= linked; }
 511   bool is_being_linked() const             { return init_state() == being_linked; }
 512   bool is_initialized() const              { return init_state() == fully_initialized; }
 513   bool is_not_initialized() const          { return init_state() <  being_initialized; }
 514   bool is_being_initialized() const        { return init_state() == being_initialized; }
 515   bool is_in_error_state() const           { return init_state() == initialization_error; }
 516   bool is_init_thread(JavaThread *thread)  { return thread == init_thread(); }
 517   ClassState  init_state() const           { return Atomic::load(&_init_state); }
 518   const char* init_state_name() const;
 519   bool is_rewritten() const                { return _misc_flags.rewritten(); }
 520 
 521   static const char* state2name(ClassState state);
 522 
 523   class LockLinkState : public StackObj {
 524     InstanceKlass* _ik;
 525     JavaThread*    _current;
 526    public:
 527     LockLinkState(InstanceKlass* ik, JavaThread* current) : _ik(ik), _current(current) {
 528       ik->check_link_state_and_wait(current);
 529     }
 530     ~LockLinkState() {
 531       if (!_ik->is_linked()) {
 532         // Reset to loaded if linking failed.
 533         _ik->set_initialization_state_and_notify(loaded, _current);
 534       }
 535     }
 536   };
 537 
 538   // is this a sealed class
 539   bool is_sealed() const;
 540 
 541   // defineClass specified verification
 542   bool should_verify_class() const         { return _misc_flags.should_verify_class(); }
 543   void set_should_verify_class(bool value) { _misc_flags.set_should_verify_class(value); }
 544 
 545   // marking
 546   bool is_marked_dependent() const         { return _misc_flags.is_marked_dependent(); }
 547   void set_is_marked_dependent(bool value) { _misc_flags.set_is_marked_dependent(value); }
 548 
 549   // initialization (virtuals from Klass)
 550   bool should_be_initialized() const;  // means that initialize should be called
 551   void initialize_from_cds(TRAPS);
 552   void initialize(TRAPS);
 553   void link_class(TRAPS);
 554   bool link_class_or_fail(TRAPS); // returns false on failure
 555   void rewrite_class(TRAPS);
 556   void link_methods(TRAPS);
 557   Method* class_initializer() const;
 558 
 559   // reference type
 560   ReferenceType reference_type() const     { return (ReferenceType)_reference_type; }
 561 
 562   // this class cp index
 563   u2 this_class_index() const             { return _this_class_index; }
 564   void set_this_class_index(u2 index)     { _this_class_index = index; }
 565 
 566   static ByteSize reference_type_offset() { return byte_offset_of(InstanceKlass, _reference_type); }
 567 
 568   // find local field, returns true if found
 569   bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 570   // find field in direct superinterfaces, returns the interface in which the field is defined
 571   Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 572   // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 573   Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 574   // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 575   Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
 576 
 577   // find a non-static or static field given its offset within the class.
 578   bool contains_field_offset(int offset);
 579 
 580   bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 581   bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 582 
 583  private:
 584   inline static int quick_search(const Array<Method*>* methods, const Symbol* name);
 585 
 586  public:
 587   static void disable_method_binary_search() {
 588     _disable_method_binary_search = true;
 589   }
 590 
 591   // find a local method (returns null if not found)
 592   Method* find_method(const Symbol* name, const Symbol* signature) const;
 593   static Method* find_method(const Array<Method*>* methods,
 594                              const Symbol* name,
 595                              const Symbol* signature);
 596 
 597   // find a local method, but skip static methods
 598   Method* find_instance_method(const Symbol* name, const Symbol* signature,
 599                                PrivateLookupMode private_mode) const;
 600   static Method* find_instance_method(const Array<Method*>* methods,
 601                                       const Symbol* name,
 602                                       const Symbol* signature,
 603                                       PrivateLookupMode private_mode);
 604 
 605   // find a local method (returns null if not found)
 606   Method* find_local_method(const Symbol* name,
 607                             const Symbol* signature,
 608                             OverpassLookupMode overpass_mode,
 609                             StaticLookupMode static_mode,
 610                             PrivateLookupMode private_mode) const;
 611 
 612   // find a local method from given methods array (returns null if not found)
 613   static Method* find_local_method(const Array<Method*>* methods,
 614                                    const Symbol* name,
 615                                    const Symbol* signature,
 616                                    OverpassLookupMode overpass_mode,
 617                                    StaticLookupMode static_mode,
 618                                    PrivateLookupMode private_mode);
 619 
 620   // find a local method index in methods or default_methods (returns -1 if not found)
 621   static int find_method_index(const Array<Method*>* methods,
 622                                const Symbol* name,
 623                                const Symbol* signature,
 624                                OverpassLookupMode overpass_mode,
 625                                StaticLookupMode static_mode,
 626                                PrivateLookupMode private_mode);
 627 
 628   // lookup operation (returns null if not found)
 629   Method* uncached_lookup_method(const Symbol* name,
 630                                  const Symbol* signature,
 631                                  OverpassLookupMode overpass_mode,
 632                                  PrivateLookupMode private_mode = PrivateLookupMode::find) const;
 633 
 634   // lookup a method in all the interfaces that this class implements
 635   // (returns null if not found)
 636   Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, DefaultsLookupMode defaults_mode) const;
 637 
 638   // lookup a method in local defaults then in all interfaces
 639   // (returns null if not found)
 640   Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
 641 
 642   // Find method indices by name.  If a method with the specified name is
 643   // found the index to the first method is returned, and 'end' is filled in
 644   // with the index of first non-name-matching method.  If no method is found
 645   // -1 is returned.
 646   int find_method_by_name(const Symbol* name, int* end) const;
 647   static int find_method_by_name(const Array<Method*>* methods,
 648                                  const Symbol* name, int* end);
 649 
 650   // constant pool
 651   ConstantPool* constants() const        { return _constants; }
 652   void set_constants(ConstantPool* c)    { _constants = c; }
 653 
 654   // protection domain
 655   oop protection_domain() const;
 656 
 657   // signers
 658   objArrayOop signers() const;
 659 
 660   bool is_contended() const                { return _misc_flags.is_contended(); }
 661   void set_is_contended(bool value)        { _misc_flags.set_is_contended(value); }
 662 
 663   // source file name
 664   Symbol* source_file_name() const;
 665   u2 source_file_name_index() const;
 666   void set_source_file_name_index(u2 sourcefile_index);
 667 
 668   // minor and major version numbers of class file
 669   u2 minor_version() const;
 670   void set_minor_version(u2 minor_version);
 671   u2 major_version() const;
 672   void set_major_version(u2 major_version);
 673 
 674   // source debug extension
 675   const char* source_debug_extension() const { return _source_debug_extension; }
 676   void set_source_debug_extension(const char* array, int length);
 677 
 678   // nonstatic oop-map blocks
 679   static int nonstatic_oop_map_size(unsigned int oop_map_count) {
 680     return oop_map_count * OopMapBlock::size_in_words();
 681   }
 682   unsigned int nonstatic_oop_map_count() const {
 683     return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
 684   }
 685   int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
 686   void set_nonstatic_oop_map_size(int words) {
 687     _nonstatic_oop_map_size = words;
 688   }
 689 
 690   bool has_contended_annotations() const { return _misc_flags.has_contended_annotations(); }
 691   void set_has_contended_annotations(bool value)  { _misc_flags.set_has_contended_annotations(value); }
 692 
 693 #if INCLUDE_JVMTI
 694   // Redefinition locking.  Class can only be redefined by one thread at a time.
 695   // The flag is in access_flags so that it can be set and reset using atomic
 696   // operations, and not be reset by other misc_flag settings.
 697   bool is_being_redefined() const          { return _misc_flags.is_being_redefined(); }
 698   void set_is_being_redefined(bool value)  { _misc_flags.set_is_being_redefined(value); }
 699 
 700   // RedefineClasses() support for previous versions:
 701   void add_previous_version(InstanceKlass* ik, int emcp_method_count);
 702   void purge_previous_version_list();
 703 
 704   InstanceKlass* previous_versions() const { return _previous_versions; }
 705 #else
 706   InstanceKlass* previous_versions() const { return nullptr; }
 707 #endif
 708 
 709   InstanceKlass* get_klass_version(int version);
 710 
 711   bool has_been_redefined() const { return _misc_flags.has_been_redefined(); }
 712   void set_has_been_redefined() { _misc_flags.set_has_been_redefined(true); }
 713 
 714   bool is_scratch_class() const { return _misc_flags.is_scratch_class(); }
 715   void set_is_scratch_class() { _misc_flags.set_is_scratch_class(true); }
 716 
 717   bool has_resolved_methods() const { return _misc_flags.has_resolved_methods(); }
 718   void set_has_resolved_methods()   { _misc_flags.set_has_resolved_methods(true); }
 719   void set_has_resolved_methods(bool value)   { _misc_flags.set_has_resolved_methods(value); }
 720 
 721 public:
 722 #if INCLUDE_JVMTI
 723 
 724   void init_previous_versions() {
 725     _previous_versions = nullptr;
 726   }
 727 
 728  private:
 729   static bool  _should_clean_previous_versions;
 730  public:
 731   static void purge_previous_versions(InstanceKlass* ik) {
 732     if (ik->has_been_redefined()) {
 733       ik->purge_previous_version_list();
 734     }
 735   }
 736 
 737   static bool should_clean_previous_versions_and_reset();
 738   static bool should_clean_previous_versions() { return _should_clean_previous_versions; }
 739 
 740   // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
 741   void set_cached_class_file(JvmtiCachedClassFileData *data) {
 742     _cached_class_file = data;
 743   }
 744   JvmtiCachedClassFileData * get_cached_class_file();
 745   jint get_cached_class_file_len();
 746   unsigned char * get_cached_class_file_bytes();
 747 
 748   // JVMTI: Support for caching of field indices, types, and offsets
 749   void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
 750     _jvmti_cached_class_field_map = descriptor;
 751   }
 752   JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
 753     return _jvmti_cached_class_field_map;
 754   }
 755 #else // INCLUDE_JVMTI
 756 
 757   static void purge_previous_versions(InstanceKlass* ik) { return; };
 758   static bool should_clean_previous_versions_and_reset() { return false; }
 759 
 760   void set_cached_class_file(JvmtiCachedClassFileData *data) {
 761     assert(data == nullptr, "unexpected call with JVMTI disabled");
 762   }
 763   JvmtiCachedClassFileData * get_cached_class_file() { return (JvmtiCachedClassFileData *)nullptr; }
 764 
 765 #endif // INCLUDE_JVMTI
 766 
 767   bool has_nonstatic_concrete_methods() const { return _misc_flags.has_nonstatic_concrete_methods(); }
 768   void set_has_nonstatic_concrete_methods(bool b) { _misc_flags.set_has_nonstatic_concrete_methods(b); }
 769 
 770   bool declares_nonstatic_concrete_methods() const { return _misc_flags.declares_nonstatic_concrete_methods(); }
 771   void set_declares_nonstatic_concrete_methods(bool b) { _misc_flags.set_declares_nonstatic_concrete_methods(b); }
 772 
 773   bool has_miranda_methods () const     { return _misc_flags.has_miranda_methods(); }
 774   void set_has_miranda_methods()        { _misc_flags.set_has_miranda_methods(true); }
 775   bool has_final_method() const         { return _misc_flags.has_final_method(); }
 776   void set_has_final_method()           { _misc_flags.set_has_final_method(true); }
 777 
 778   // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
 779   inline u2 next_method_idnum();
 780   void set_initial_method_idnum(u2 value)             { _idnum_allocated_count = value; }
 781 
 782   // generics support
 783   Symbol* generic_signature() const;
 784   u2 generic_signature_index() const;
 785   void set_generic_signature_index(u2 sig_index);
 786 
 787   u2 enclosing_method_data(int offset) const;
 788   u2 enclosing_method_class_index() const {
 789     return enclosing_method_data(enclosing_method_class_index_offset);
 790   }
 791   u2 enclosing_method_method_index() {
 792     return enclosing_method_data(enclosing_method_method_index_offset);
 793   }
 794   void set_enclosing_method_indices(u2 class_index,
 795                                     u2 method_index);
 796 
 797   // jmethodID support
 798   jmethodID get_jmethod_id(const methodHandle& method_h);
 799   void ensure_space_for_methodids(int start_offset = 0);
 800   jmethodID jmethod_id_or_null(Method* method);
 801   void update_methods_jmethod_cache();
 802 
 803   // annotations support
 804   Annotations* annotations() const          { return _annotations; }
 805   void set_annotations(Annotations* anno)   { _annotations = anno; }
 806 
 807   AnnotationArray* class_annotations() const {
 808     return (_annotations != nullptr) ? _annotations->class_annotations() : nullptr;
 809   }
 810   Array<AnnotationArray*>* fields_annotations() const {
 811     return (_annotations != nullptr) ? _annotations->fields_annotations() : nullptr;
 812   }
 813   AnnotationArray* class_type_annotations() const {
 814     return (_annotations != nullptr) ? _annotations->class_type_annotations() : nullptr;
 815   }
 816   Array<AnnotationArray*>* fields_type_annotations() const {
 817     return (_annotations != nullptr) ? _annotations->fields_type_annotations() : nullptr;
 818   }
 819   // allocation
 820   instanceOop allocate_instance(TRAPS);
 821   static instanceOop allocate_instance(oop cls, const char* who, TRAPS);
 822 
 823   // additional member function to return a handle
 824   instanceHandle allocate_instance_handle(TRAPS);
 825 
 826   objArrayOop allocate_objArray(int n, int length, TRAPS);
 827   // Helper function
 828   static instanceOop register_finalizer(instanceOop i, TRAPS);
 829 
 830   // Check whether reflection/jni/jvm code is allowed to instantiate this class;
 831   // if not, throw either an Error or an Exception.
 832   virtual void check_valid_for_instantiation(bool throwError, TRAPS);
 833 
 834   // initialization
 835   void call_class_initializer(TRAPS);
 836   void set_initialization_state_and_notify(ClassState state, JavaThread* current);
 837 
 838   // OopMapCache support
 839   OopMapCache* oop_map_cache()               { return _oop_map_cache; }
 840   void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
 841   void mask_for(const methodHandle& method, int bci, InterpreterOopMap* entry);
 842 
 843   // JNI identifier support (for static fields - for jni performance)
 844   JNIid* jni_ids()                               { return _jni_ids; }
 845   void set_jni_ids(JNIid* ids)                   { _jni_ids = ids; }
 846   JNIid* jni_id_for(int offset);
 847 
 848   // maintenance of deoptimization dependencies
 849   inline DependencyContext dependencies();
 850   void mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes);
 851   void add_dependent_nmethod(nmethod* nm);
 852   void clean_dependency_context();
 853   // Setup link to hierarchy and deoptimize
 854   void add_to_hierarchy(JavaThread* current);
 855 
 856   // On-stack replacement support
 857   nmethod* osr_nmethods_head() const         { return _osr_nmethods_head; };
 858   void set_osr_nmethods_head(nmethod* h)     { _osr_nmethods_head = h; };
 859   void add_osr_nmethod(nmethod* n);
 860   bool remove_osr_nmethod(nmethod* n);
 861   int mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m);
 862   nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
 863 
 864 #if INCLUDE_JVMTI
 865   // Breakpoint support (see methods on Method* for details)
 866   BreakpointInfo* breakpoints() const       { return _breakpoints; };
 867   void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
 868 #endif
 869 
 870   // support for stub routines
 871   static ByteSize init_state_offset()  { return byte_offset_of(InstanceKlass, _init_state); }
 872   JFR_ONLY(DEFINE_KLASS_TRACE_ID_OFFSET;)
 873   static ByteSize init_thread_offset() { return byte_offset_of(InstanceKlass, _init_thread); }
 874 
 875   // subclass/subinterface checks
 876   bool implements_interface(Klass* k) const;
 877   bool is_same_or_direct_interface(Klass* k) const;
 878 
 879 #ifdef ASSERT
 880   // check whether this class or one of its superclasses was redefined
 881   bool has_redefined_this_or_super() const;
 882 #endif
 883 
 884   // Access to the implementor of an interface.
 885   InstanceKlass* implementor() const;
 886   void set_implementor(InstanceKlass* ik);
 887   int  nof_implementors() const;
 888   void add_implementor(InstanceKlass* ik);  // ik is a new class that implements this interface
 889   void init_implementor();           // initialize
 890 
 891  private:
 892   // link this class into the implementors list of every interface it implements
 893   void process_interfaces();
 894 
 895  public:
 896   // virtual operations from Klass
 897   GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
 898                                                   Array<InstanceKlass*>* transitive_interfaces);
 899   bool can_be_primary_super_slow() const;
 900   size_t oop_size(oop obj)  const             { return size_helper(); }
 901   // slow because it's a virtual call and used for verifying the layout_helper.
 902   // Using the layout_helper bits, we can call is_instance_klass without a virtual call.
 903   DEBUG_ONLY(bool is_instance_klass_slow() const      { return true; })
 904 
 905   // Iterators
 906   void do_local_static_fields(FieldClosure* cl);
 907   void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
 908   void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
 909   void print_nonstatic_fields(FieldClosure* cl); // including inherited and injected fields
 910 
 911   void methods_do(void f(Method* method));
 912 
 913   static InstanceKlass* cast(Klass* k) {
 914     return const_cast<InstanceKlass*>(cast(const_cast<const Klass*>(k)));
 915   }
 916 
 917   static const InstanceKlass* cast(const Klass* k) {
 918     assert(k != nullptr, "k should not be null");
 919     assert(k->is_instance_klass(), "cast to InstanceKlass");
 920     return static_cast<const InstanceKlass*>(k);
 921   }
 922 
 923   virtual InstanceKlass* java_super() const {
 924     return (super() == nullptr) ? nullptr : cast(super());
 925   }
 926 
 927   // Sizing (in words)
 928   static int header_size()            { return sizeof(InstanceKlass)/wordSize; }
 929 
 930   static int size(int vtable_length, int itable_length,
 931                   int nonstatic_oop_map_size,
 932                   bool is_interface) {
 933     return align_metadata_size(header_size() +
 934            vtable_length +
 935            itable_length +
 936            nonstatic_oop_map_size +
 937            (is_interface ? (int)sizeof(Klass*)/wordSize : 0));
 938   }
 939 
 940   int size() const                    { return size(vtable_length(),
 941                                                itable_length(),
 942                                                nonstatic_oop_map_size(),
 943                                                is_interface());
 944   }
 945 
 946 
 947   inline intptr_t* start_of_itable() const;
 948   inline intptr_t* end_of_itable() const;
 949   inline oop static_field_base_raw();
 950 
 951   inline OopMapBlock* start_of_nonstatic_oop_maps() const;
 952   inline Klass** end_of_nonstatic_oop_maps() const;
 953 
 954   inline InstanceKlass* volatile* adr_implementor() const;
 955 
 956   // Use this to return the size of an instance in heap words:
 957   int size_helper() const {
 958     return layout_helper_to_size_helper(layout_helper());
 959   }
 960 
 961   // This bit is initialized in classFileParser.cpp.
 962   // It is false under any of the following conditions:
 963   //  - the class is abstract (including any interface)
 964   //  - the class size is larger than FastAllocateSizeLimit
 965   //  - the class is java/lang/Class, which cannot be allocated directly
 966   bool can_be_fastpath_allocated() const {
 967     return !layout_helper_needs_slow_path(layout_helper());
 968   }
 969 
 970   // Java itable
 971   klassItable itable() const;        // return klassItable wrapper
 972   Method* method_at_itable(InstanceKlass* holder, int index, TRAPS);
 973   Method* method_at_itable_or_null(InstanceKlass* holder, int index, bool& itable_entry_found);
 974   int vtable_index_of_interface_method(Method* method);
 975 
 976 #if INCLUDE_JVMTI
 977   void adjust_default_methods(bool* trace_name_printed);
 978 #endif // INCLUDE_JVMTI
 979 
 980   void clean_weak_instanceklass_links();
 981  private:
 982   void clean_implementors_list();
 983   void clean_method_data();
 984 
 985  public:
 986   // Explicit metaspace deallocation of fields
 987   // For RedefineClasses and class file parsing errors, we need to deallocate
 988   // instanceKlasses and the metadata they point to.
 989   void deallocate_contents(ClassLoaderData* loader_data);
 990   static void deallocate_methods(ClassLoaderData* loader_data,
 991                                  Array<Method*>* methods);
 992   void static deallocate_interfaces(ClassLoaderData* loader_data,
 993                                     const Klass* super_klass,
 994                                     Array<InstanceKlass*>* local_interfaces,
 995                                     Array<InstanceKlass*>* transitive_interfaces);
 996   void static deallocate_record_components(ClassLoaderData* loader_data,
 997                                            Array<RecordComponent*>* record_component);
 998 
 999   virtual bool on_stack() const;
1000 
1001   // callbacks for actions during class unloading
1002   static void unload_class(InstanceKlass* ik);
1003 
1004   virtual void release_C_heap_structures(bool release_sub_metadata = true);
1005 
1006   // Naming
1007   const char* signature_name() const;
1008 
1009   // Oop fields (and metadata) iterators
1010   //
1011   // The InstanceKlass iterators also visits the Object's klass.
1012 
1013   // Forward iteration
1014  public:
1015   // Iterate over all oop fields in the oop maps.
1016   template <typename T, class OopClosureType>
1017   inline void oop_oop_iterate_oop_maps(oop obj, OopClosureType* closure);
1018 
1019   // Iterate over all oop fields and metadata.
1020   template <typename T, class OopClosureType>
1021   inline void oop_oop_iterate(oop obj, OopClosureType* closure);
1022 
1023   // Iterate over all oop fields in one oop map.
1024   template <typename T, class OopClosureType>
1025   inline void oop_oop_iterate_oop_map(OopMapBlock* map, oop obj, OopClosureType* closure);
1026 
1027 
1028   // Reverse iteration
1029   // Iterate over all oop fields and metadata.
1030   template <typename T, class OopClosureType>
1031   inline void oop_oop_iterate_reverse(oop obj, OopClosureType* closure);
1032 
1033  private:
1034   // Iterate over all oop fields in the oop maps.
1035   template <typename T, class OopClosureType>
1036   inline void oop_oop_iterate_oop_maps_reverse(oop obj, OopClosureType* closure);
1037 
1038   // Iterate over all oop fields in one oop map.
1039   template <typename T, class OopClosureType>
1040   inline void oop_oop_iterate_oop_map_reverse(OopMapBlock* map, oop obj, OopClosureType* closure);
1041 
1042 
1043   // Bounded range iteration
1044  public:
1045   // Iterate over all oop fields in the oop maps.
1046   template <typename T, class OopClosureType>
1047   inline void oop_oop_iterate_oop_maps_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1048 
1049   // Iterate over all oop fields and metadata.
1050   template <typename T, class OopClosureType>
1051   inline void oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1052 
1053  private:
1054   // Iterate over all oop fields in one oop map.
1055   template <typename T, class OopClosureType>
1056   inline void oop_oop_iterate_oop_map_bounded(OopMapBlock* map, oop obj, OopClosureType* closure, MemRegion mr);
1057 
1058 
1059  public:
1060   u2 idnum_allocated_count() const      { return _idnum_allocated_count; }
1061 
1062  private:
1063   // initialization state
1064   void set_init_state(ClassState state);
1065   void set_rewritten()                  { _misc_flags.set_rewritten(true); }
1066   void set_init_thread(JavaThread *thread)  {
1067     assert((thread == JavaThread::current() && _init_thread == nullptr) ||
1068            (thread == nullptr && _init_thread == JavaThread::current()), "Only one thread is allowed to own initialization");
1069     Atomic::store(&_init_thread, thread);
1070   }
1071 
1072   inline jmethodID* methods_jmethod_ids_acquire() const;
1073   inline void release_set_methods_jmethod_ids(jmethodID* jmeths);
1074   // This nulls out jmethodIDs for all methods in 'klass'
1075   static void clear_jmethod_ids(InstanceKlass* klass);
1076   jmethodID update_jmethod_id(jmethodID* jmeths, Method* method, int idnum);
1077 
1078 public:
1079   // Returns the array class for the n'th dimension
1080   virtual ArrayKlass* array_klass(int n, TRAPS);
1081   virtual ArrayKlass* array_klass_or_null(int n);
1082 
1083   // Returns the array class with this class as element type
1084   virtual ArrayKlass* array_klass(TRAPS);
1085   virtual ArrayKlass* array_klass_or_null();
1086 
1087   static void clean_initialization_error_table();
1088 
1089   Monitor* init_monitor() const { return _init_monitor; }
1090 private:
1091   void check_link_state_and_wait(JavaThread* current);
1092   bool link_class_impl                           (TRAPS);
1093   bool verify_code                               (TRAPS);
1094   void initialize_impl                           (TRAPS);
1095   void initialize_super_interfaces(TRAPS);
1096 
1097   void add_initialization_error(JavaThread* current, Handle exception);
1098   oop get_initialization_error(JavaThread* current);
1099 
1100   // find a local method (returns null if not found)
1101   Method* find_method_impl(const Symbol* name,
1102                            const Symbol* signature,
1103                            OverpassLookupMode overpass_mode,
1104                            StaticLookupMode static_mode,
1105                            PrivateLookupMode private_mode) const;
1106 
1107   static Method* find_method_impl(const Array<Method*>* methods,
1108                                   const Symbol* name,
1109                                   const Symbol* signature,
1110                                   OverpassLookupMode overpass_mode,
1111                                   StaticLookupMode static_mode,
1112                                   PrivateLookupMode private_mode);
1113 
1114 #if INCLUDE_JVMTI
1115   // RedefineClasses support
1116   void link_previous_versions(InstanceKlass* pv) { _previous_versions = pv; }
1117   void mark_newly_obsolete_methods(Array<Method*>* old_methods, int emcp_method_count);
1118 #endif
1119   // log class name to classlist
1120   void log_to_classlist() const;
1121 public:
1122 
1123 #if INCLUDE_CDS
1124   // CDS support - remove and restore oops from metadata. Oops are not shared.
1125   virtual void remove_unshareable_info();
1126   void remove_unshareable_flags();
1127   virtual void remove_java_mirror();
1128   void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, PackageEntry* pkg_entry, TRAPS);
1129   void init_shared_package_entry();
1130   bool can_be_verified_at_dumptime() const;
1131   bool methods_contain_jsr_bytecode() const;
1132   void compute_has_loops_flag_for_methods();
1133 #endif
1134 
1135   bool     has_init_deps_processed() const { return _misc_flags.has_init_deps_processed(); }
1136   void set_has_init_deps_processed() {
1137     assert(is_initialized(), "");
1138     assert(!has_init_deps_processed(), "already set"); // one-off action
1139     _misc_flags.set_has_init_deps_processed(true);
1140   }
1141 
1142   jint compute_modifier_flags() const;
1143 
1144 public:
1145   // JVMTI support
1146   jint jvmti_class_status() const;
1147 
1148   virtual void metaspace_pointers_do(MetaspaceClosure* iter);
1149 
1150  public:
1151   // Printing
1152   void print_on(outputStream* st) const;
1153   void print_value_on(outputStream* st) const;
1154 
1155   void oop_print_value_on(oop obj, outputStream* st);
1156 
1157   void oop_print_on      (oop obj, outputStream* st);
1158 
1159 #ifndef PRODUCT
1160   void print_dependent_nmethods(bool verbose = false);
1161   bool is_dependent_nmethod(nmethod* nm);
1162   bool verify_itable_index(int index);
1163 #endif
1164 
1165   const char* internal_name() const;
1166 
1167   // Verification
1168   void verify_on(outputStream* st);
1169 
1170   void oop_verify_on(oop obj, outputStream* st);
1171 
1172   // Logging
1173   void print_class_load_logging(ClassLoaderData* loader_data,
1174                                 const ModuleEntry* module_entry,
1175                                 const ClassFileStream* cfs) const;
1176  private:
1177   void print_class_load_cause_logging() const;
1178   void print_class_load_helper(ClassLoaderData* loader_data,
1179                                const ModuleEntry* module_entry,
1180                                const ClassFileStream* cfs) const;
1181 };
1182 
1183 // for adding methods
1184 // UNSET_IDNUM return means no more ids available
1185 inline u2 InstanceKlass::next_method_idnum() {
1186   if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1187     return ConstMethod::UNSET_IDNUM; // no more ids available
1188   } else {
1189     return _idnum_allocated_count++;
1190   }
1191 }
1192 
1193 class PrintClassClosure : public KlassClosure {
1194 private:
1195   outputStream* _st;
1196   bool _verbose;
1197 public:
1198   PrintClassClosure(outputStream* st, bool verbose);
1199 
1200   void do_klass(Klass* k);
1201 };
1202 
1203 /* JNIid class for jfieldIDs only */
1204 class JNIid: public CHeapObj<mtClass> {
1205   friend class VMStructs;
1206  private:
1207   Klass*             _holder;
1208   JNIid*             _next;
1209   int                _offset;
1210 #ifdef ASSERT
1211   bool               _is_static_field_id;
1212 #endif
1213 
1214  public:
1215   // Accessors
1216   Klass* holder() const           { return _holder; }
1217   int offset() const              { return _offset; }
1218   JNIid* next()                   { return _next; }
1219   // Constructor
1220   JNIid(Klass* holder, int offset, JNIid* next);
1221   // Identifier lookup
1222   JNIid* find(int offset);
1223 
1224   bool find_local_field(fieldDescriptor* fd) {
1225     return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1226   }
1227 
1228   static void deallocate(JNIid* id);
1229   // Debugging
1230 #ifdef ASSERT
1231   bool is_static_field_id() const { return _is_static_field_id; }
1232   void set_is_static_field_id()   { _is_static_field_id = true; }
1233 #endif
1234   void verify(Klass* holder);
1235 };
1236 
1237 // An iterator that's used to access the inner classes indices in the
1238 // InstanceKlass::_inner_classes array.
1239 class InnerClassesIterator : public StackObj {
1240  private:
1241   Array<jushort>* _inner_classes;
1242   int _length;
1243   int _idx;
1244  public:
1245 
1246   InnerClassesIterator(const InstanceKlass* k) {
1247     _inner_classes = k->inner_classes();
1248     if (k->inner_classes() != nullptr) {
1249       _length = _inner_classes->length();
1250       // The inner class array's length should be the multiple of
1251       // inner_class_next_offset if it only contains the InnerClasses
1252       // attribute data, or it should be
1253       // n*inner_class_next_offset+enclosing_method_attribute_size
1254       // if it also contains the EnclosingMethod data.
1255       assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1256               _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1257              "just checking");
1258       // Remove the enclosing_method portion if exists.
1259       if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1260         _length -= InstanceKlass::enclosing_method_attribute_size;
1261       }
1262     } else {
1263       _length = 0;
1264     }
1265     _idx = 0;
1266   }
1267 
1268   int length() const {
1269     return _length;
1270   }
1271 
1272   void next() {
1273     _idx += InstanceKlass::inner_class_next_offset;
1274   }
1275 
1276   bool done() const {
1277     return (_idx >= _length);
1278   }
1279 
1280   u2 inner_class_info_index() const {
1281     return _inner_classes->at(
1282                _idx + InstanceKlass::inner_class_inner_class_info_offset);
1283   }
1284 
1285   void set_inner_class_info_index(u2 index) {
1286     _inner_classes->at_put(
1287                _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1288   }
1289 
1290   u2 outer_class_info_index() const {
1291     return _inner_classes->at(
1292                _idx + InstanceKlass::inner_class_outer_class_info_offset);
1293   }
1294 
1295   void set_outer_class_info_index(u2 index) {
1296     _inner_classes->at_put(
1297                _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1298   }
1299 
1300   u2 inner_name_index() const {
1301     return _inner_classes->at(
1302                _idx + InstanceKlass::inner_class_inner_name_offset);
1303   }
1304 
1305   void set_inner_name_index(u2 index) {
1306     _inner_classes->at_put(
1307                _idx + InstanceKlass::inner_class_inner_name_offset, index);
1308   }
1309 
1310   u2 inner_access_flags() const {
1311     return _inner_classes->at(
1312                _idx + InstanceKlass::inner_class_access_flags_offset);
1313   }
1314 };
1315 
1316 // Iterator over class hierarchy under a particular class. Implements depth-first pre-order traversal.
1317 // Usage:
1318 //  for (ClassHierarchyIterator iter(root_klass); !iter.done(); iter.next()) {
1319 //    Klass* k = iter.klass();
1320 //    ...
1321 //  }
1322 class ClassHierarchyIterator : public StackObj {
1323  private:
1324   InstanceKlass* _root;
1325   Klass*         _current;
1326   bool           _visit_subclasses;
1327 
1328  public:
1329   ClassHierarchyIterator(InstanceKlass* root) : _root(root), _current(root), _visit_subclasses(true) {
1330     assert(_root == _current, "required"); // initial state
1331   }
1332 
1333   bool done() {
1334     return (_current == nullptr);
1335   }
1336 
1337   // Make a step iterating over the class hierarchy under the root class.
1338   // Skips subclasses if requested.
1339   void next();
1340 
1341   Klass* klass() {
1342     assert(!done(), "sanity");
1343     return _current;
1344   }
1345 
1346   // Skip subclasses of the current class.
1347   void skip_subclasses() {
1348     _visit_subclasses = false;
1349   }
1350 };
1351 
1352 #endif // SHARE_OOPS_INSTANCEKLASS_HPP