1 /*
   2  * Copyright (c) 1997, 2017, 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_VM_OOPS_INSTANCEKLASS_HPP
  26 #define SHARE_VM_OOPS_INSTANCEKLASS_HPP
  27 
  28 #include "classfile/classLoader.hpp"
  29 #include "classfile/classLoaderData.hpp"
  30 #include "classfile/moduleEntry.hpp"
  31 #include "classfile/packageEntry.hpp"
  32 #include "gc/shared/specialized_oop_closures.hpp"
  33 #include "memory/referenceType.hpp"
  34 #include "oops/annotations.hpp"
  35 #include "oops/constMethod.hpp"
  36 #include "oops/fieldInfo.hpp"
  37 #include "oops/instanceOop.hpp"
  38 #include "oops/klassVtable.hpp"
  39 #include "runtime/handles.hpp"
  40 #include "runtime/os.hpp"
  41 #include "trace/traceMacros.hpp"
  42 #include "utilities/accessFlags.hpp"
  43 #include "utilities/macros.hpp"
  44 
  45 // An InstanceKlass is the VM level representation of a Java class.
  46 // It contains all information needed for at class at execution runtime.
  47 
  48 //  InstanceKlass embedded field layout (after declared fields):
  49 //    [EMBEDDED Java vtable             ] size in words = vtable_len
  50 //    [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
  51 //      The embedded nonstatic oop-map blocks are short pairs (offset, length)
  52 //      indicating where oops are located in instances of this klass.
  53 //    [EMBEDDED implementor of the interface] only exist for interface
  54 //    [EMBEDDED host klass        ] only exist for an anonymous class (JSR 292 enabled)
  55 //    [EMBEDDED fingerprint       ] only if should_store_fingerprint()==true
  56 
  57 
  58 // forward declaration for class -- see below for definition
  59 #if INCLUDE_JVMTI
  60 class BreakpointInfo;
  61 #endif
  62 class ClassFileParser;
  63 class KlassDepChange;
  64 class DependencyContext;
  65 class fieldDescriptor;
  66 class jniIdMapBase;
  67 class JNIid;
  68 class JvmtiCachedClassFieldMap;
  69 class SuperTypeClosure;
  70 
  71 // This is used in iterators below.
  72 class FieldClosure: public StackObj {
  73 public:
  74   virtual void do_field(fieldDescriptor* fd) = 0;
  75 };
  76 
  77 #ifndef PRODUCT
  78 // Print fields.
  79 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
  80 class FieldPrinter: public FieldClosure {
  81    oop _obj;
  82    outputStream* _st;
  83  public:
  84    FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
  85    void do_field(fieldDescriptor* fd);
  86 };
  87 #endif  // !PRODUCT
  88 
  89 // ValueObjs embedded in klass. Describes where oops are located in instances of
  90 // this klass.
  91 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
  92  public:
  93   // Byte offset of the first oop mapped by this block.
  94   int offset() const          { return _offset; }
  95   void set_offset(int offset) { _offset = offset; }
  96 
  97   // Number of oops in this block.
  98   uint count() const         { return _count; }
  99   void set_count(uint count) { _count = count; }
 100 
 101   // sizeof(OopMapBlock) in words.
 102   static const int size_in_words() {
 103     return align_size_up((int)sizeof(OopMapBlock), wordSize) >>
 104       LogBytesPerWord;
 105   }
 106 
 107  private:
 108   int  _offset;
 109   uint _count;
 110 };
 111 
 112 struct JvmtiCachedClassFileData;
 113 
 114 class InstanceKlass: public Klass {
 115   friend class VMStructs;
 116   friend class JVMCIVMStructs;
 117   friend class ClassFileParser;
 118   friend class CompileReplay;
 119 
 120  protected:
 121   InstanceKlass(const ClassFileParser& parser, unsigned kind);
 122 
 123  public:
 124   InstanceKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
 125 
 126   // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
 127   // of the class loading & initialization procedure, and the use of the states.
 128   enum ClassState {
 129     allocated,                          // allocated (but not yet linked)
 130     loaded,                             // loaded and inserted in class hierarchy (but not linked yet)
 131     linked,                             // successfully linked/verified (but not initialized yet)
 132     being_initialized,                  // currently running class initializer
 133     fully_initialized,                  // initialized (successfull final state)
 134     initialization_error                // error happened during initialization
 135   };
 136 
 137   static int number_of_instance_classes() { return _total_instanceKlass_count; }
 138 
 139  private:
 140   static volatile int _total_instanceKlass_count;
 141   static InstanceKlass* allocate_instance_klass(const ClassFileParser& parser, TRAPS);
 142 
 143  protected:
 144   // Annotations for this class
 145   Annotations*    _annotations;
 146   // Package this class is defined in
 147   PackageEntry*   _package_entry;
 148   // Array classes holding elements of this class.
 149   Klass* volatile _array_klasses;
 150   // Constant pool for this class.
 151   ConstantPool* _constants;
 152   // The InnerClasses attribute and EnclosingMethod attribute. The
 153   // _inner_classes is an array of shorts. If the class has InnerClasses
 154   // attribute, then the _inner_classes array begins with 4-tuples of shorts
 155   // [inner_class_info_index, outer_class_info_index,
 156   // inner_name_index, inner_class_access_flags] for the InnerClasses
 157   // attribute. If the EnclosingMethod attribute exists, it occupies the
 158   // last two shorts [class_index, method_index] of the array. If only
 159   // the InnerClasses attribute exists, the _inner_classes array length is
 160   // number_of_inner_classes * 4. If the class has both InnerClasses
 161   // and EnclosingMethod attributes the _inner_classes array length is
 162   // number_of_inner_classes * 4 + enclosing_method_attribute_size.
 163   Array<jushort>* _inner_classes;
 164 
 165   // the source debug extension for this klass, NULL if not specified.
 166   // Specified as UTF-8 string without terminating zero byte in the classfile,
 167   // it is stored in the instanceklass as a NULL-terminated UTF-8 string
 168   const char*     _source_debug_extension;
 169   // Array name derived from this class which needs unreferencing
 170   // if this class is unloaded.
 171   Symbol*         _array_name;
 172 
 173   // Number of heapOopSize words used by non-static fields in this klass
 174   // (including inherited fields but after header_size()).
 175   int             _nonstatic_field_size;
 176   int             _static_field_size;    // number words used by static fields (oop and non-oop) in this klass
 177   // Constant pool index to the utf8 entry of the Generic signature,
 178   // or 0 if none.
 179   u2              _generic_signature_index;
 180   // Constant pool index to the utf8 entry for the name of source file
 181   // containing this klass, 0 if not specified.
 182   u2              _source_file_name_index;
 183   u2              _static_oop_field_count;// number of static oop fields in this klass
 184   u2              _java_fields_count;    // The number of declared Java fields
 185   int             _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks
 186 
 187   int             _itable_len;           // length of Java itable (in words)
 188   // _is_marked_dependent can be set concurrently, thus cannot be part of the
 189   // _misc_flags.
 190   bool            _is_marked_dependent;  // used for marking during flushing and deoptimization
 191   bool            _is_being_redefined;   // used for locking redefinition
 192 
 193   // The low two bits of _misc_flags contains the kind field.
 194   // This can be used to quickly discriminate among the four kinds of
 195   // InstanceKlass.
 196 
 197   static const unsigned _misc_kind_field_size = 2;
 198   static const unsigned _misc_kind_field_pos  = 0;
 199   static const unsigned _misc_kind_field_mask = (1u << _misc_kind_field_size) - 1u;
 200 
 201   static const unsigned _misc_kind_other        = 0; // concrete InstanceKlass
 202   static const unsigned _misc_kind_reference    = 1; // InstanceRefKlass
 203   static const unsigned _misc_kind_class_loader = 2; // InstanceClassLoaderKlass
 204   static const unsigned _misc_kind_mirror       = 3; // InstanceMirrorKlass
 205 
 206   // Start after _misc_kind field.
 207   enum {
 208     _misc_rewritten                           = 1 << 2,  // methods rewritten.
 209     _misc_has_nonstatic_fields                = 1 << 3,  // for sizing with UseCompressedOops
 210     _misc_should_verify_class                 = 1 << 4,  // allow caching of preverification
 211     _misc_is_anonymous                        = 1 << 5,  // has embedded _host_klass field
 212     _misc_is_contended                        = 1 << 6,  // marked with contended annotation
 213     _misc_has_nonstatic_concrete_methods      = 1 << 7,  // class/superclass/implemented interfaces has non-static, concrete methods
 214     _misc_declares_nonstatic_concrete_methods = 1 << 8,  // directly declares non-static, concrete methods
 215     _misc_has_been_redefined                  = 1 << 9,  // class has been redefined
 216     _misc_has_passed_fingerprint_check        = 1 << 10, // when this class was loaded, the fingerprint computed from its
 217                                                          // code source was found to be matching the value recorded by AOT.
 218     _misc_is_scratch_class                    = 1 << 11, // class is the redefined scratch class
 219     _misc_is_shared_boot_class                = 1 << 12, // defining class loader is boot class loader
 220     _misc_is_shared_platform_class            = 1 << 13, // defining class loader is platform class loader
 221     _misc_is_shared_app_class                 = 1 << 14, // defining class loader is app class loader
 222     _misc_has_resolved_methods                = 1 << 15  // resolved methods table entries added for this class
 223   };
 224   u2 loader_type_bits() {
 225     return _misc_is_shared_boot_class|_misc_is_shared_platform_class|_misc_is_shared_app_class;
 226   }
 227   u2              _misc_flags;
 228   u2              _minor_version;        // minor version number of class file
 229   u2              _major_version;        // major version number of class file
 230   Thread*         _init_thread;          // Pointer to current thread doing initialization (to handle recusive initialization)
 231   OopMapCache*    volatile _oop_map_cache;   // OopMapCache for all methods in the klass (allocated lazily)
 232   JNIid*          _jni_ids;              // First JNI identifier for static fields in this class
 233   jmethodID*      volatile _methods_jmethod_ids;  // jmethodIDs corresponding to method_idnum, or NULL if none
 234   intptr_t        _dep_context;          // packed DependencyContext structure
 235   nmethod*        _osr_nmethods_head;    // Head of list of on-stack replacement nmethods for this class
 236 #if INCLUDE_JVMTI
 237   BreakpointInfo* _breakpoints;          // bpt lists, managed by Method*
 238   // Linked instanceKlasses of previous versions
 239   InstanceKlass* _previous_versions;
 240   // JVMTI fields can be moved to their own structure - see 6315920
 241   // JVMTI: cached class file, before retransformable agent modified it in CFLH
 242   JvmtiCachedClassFileData* _cached_class_file;
 243 #endif
 244 
 245   volatile u2     _idnum_allocated_count;         // JNI/JVMTI: increments with the addition of methods, old ids don't change
 246 
 247   // Class states are defined as ClassState (see above).
 248   // Place the _init_state here to utilize the unused 2-byte after
 249   // _idnum_allocated_count.
 250   u1              _init_state;                    // state of class
 251   u1              _reference_type;                // reference type
 252 
 253 #if INCLUDE_JVMTI
 254   JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map;  // JVMTI: used during heap iteration
 255 #endif
 256 
 257   NOT_PRODUCT(int _verify_count;)  // to avoid redundant verifies
 258 
 259   // Method array.
 260   Array<Method*>* _methods;
 261   // Default Method Array, concrete methods inherited from interfaces
 262   Array<Method*>* _default_methods;
 263   // Interface (Klass*s) this class declares locally to implement.
 264   Array<Klass*>* _local_interfaces;
 265   // Interface (Klass*s) this class implements transitively.
 266   Array<Klass*>* _transitive_interfaces;
 267   // Int array containing the original order of method in the class file (for JVMTI).
 268   Array<int>*     _method_ordering;
 269   // Int array containing the vtable_indices for default_methods
 270   // offset matches _default_methods offset
 271   Array<int>*     _default_vtable_indices;
 272 
 273   // Instance and static variable information, starts with 6-tuples of shorts
 274   // [access, name index, sig index, initval index, low_offset, high_offset]
 275   // for all fields, followed by the generic signature data at the end of
 276   // the array. Only fields with generic signature attributes have the generic
 277   // signature data set in the array. The fields array looks like following:
 278   //
 279   // f1: [access, name index, sig index, initial value index, low_offset, high_offset]
 280   // f2: [access, name index, sig index, initial value index, low_offset, high_offset]
 281   //      ...
 282   // fn: [access, name index, sig index, initial value index, low_offset, high_offset]
 283   //     [generic signature index]
 284   //     [generic signature index]
 285   //     ...
 286   Array<u2>*      _fields;
 287 
 288   // embedded Java vtable follows here
 289   // embedded Java itables follows here
 290   // embedded static fields follows here
 291   // embedded nonstatic oop-map blocks follows here
 292   // embedded implementor of this interface follows here
 293   //   The embedded implementor only exists if the current klass is an
 294   //   iterface. The possible values of the implementor fall into following
 295   //   three cases:
 296   //     NULL: no implementor.
 297   //     A Klass* that's not itself: one implementor.
 298   //     Itself: more than one implementors.
 299   // embedded host klass follows here
 300   //   The embedded host klass only exists in an anonymous class for
 301   //   dynamic language support (JSR 292 enabled). The host class grants
 302   //   its access privileges to this class also. The host class is either
 303   //   named, or a previously loaded anonymous class. A non-anonymous class
 304   //   or an anonymous class loaded through normal classloading does not
 305   //   have this embedded field.
 306   //
 307 
 308   friend class SystemDictionary;
 309 
 310  public:
 311   u2 loader_type() {
 312     return _misc_flags & loader_type_bits();
 313   }
 314 
 315   bool is_shared_boot_class() const {
 316     return (_misc_flags & _misc_is_shared_boot_class) != 0;
 317   }
 318   bool is_shared_platform_class() const {
 319     return (_misc_flags & _misc_is_shared_platform_class) != 0;
 320   }
 321   bool is_shared_app_class() const {
 322     return (_misc_flags & _misc_is_shared_app_class) != 0;
 323   }
 324 
 325   void set_class_loader_type(s2 loader_type) {
 326     assert(( _misc_flags & loader_type_bits()) == 0,
 327            "Should only be called once for each class.");
 328     switch (loader_type) {
 329     case ClassLoader::BOOT_LOADER:
 330       _misc_flags |= _misc_is_shared_boot_class;
 331        break;
 332     case ClassLoader::PLATFORM_LOADER:
 333       _misc_flags |= _misc_is_shared_platform_class;
 334       break;
 335     case ClassLoader::APP_LOADER:
 336       _misc_flags |= _misc_is_shared_app_class;
 337       break;
 338     default:
 339       ShouldNotReachHere();
 340       break;
 341     }
 342   }
 343 
 344   bool has_nonstatic_fields() const        {
 345     return (_misc_flags & _misc_has_nonstatic_fields) != 0;
 346   }
 347   void set_has_nonstatic_fields(bool b)    {
 348     if (b) {
 349       _misc_flags |= _misc_has_nonstatic_fields;
 350     } else {
 351       _misc_flags &= ~_misc_has_nonstatic_fields;
 352     }
 353   }
 354 
 355   // field sizes
 356   int nonstatic_field_size() const         { return _nonstatic_field_size; }
 357   void set_nonstatic_field_size(int size)  { _nonstatic_field_size = size; }
 358 
 359   int static_field_size() const            { return _static_field_size; }
 360   void set_static_field_size(int size)     { _static_field_size = size; }
 361 
 362   int static_oop_field_count() const       { return (int)_static_oop_field_count; }
 363   void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
 364 
 365   // Java itable
 366   int  itable_length() const               { return _itable_len; }
 367   void set_itable_length(int len)          { _itable_len = len; }
 368 
 369   // array klasses
 370   Klass* array_klasses() const             { return _array_klasses; }
 371   inline Klass* array_klasses_acquire() const; // load with acquire semantics
 372   void set_array_klasses(Klass* k)         { _array_klasses = k; }
 373   inline void release_set_array_klasses(Klass* k); // store with release semantics
 374 
 375   // methods
 376   Array<Method*>* methods() const          { return _methods; }
 377   void set_methods(Array<Method*>* a)      { _methods = a; }
 378   Method* method_with_idnum(int idnum);
 379   Method* method_with_orig_idnum(int idnum);
 380   Method* method_with_orig_idnum(int idnum, int version);
 381 
 382   // method ordering
 383   Array<int>* method_ordering() const     { return _method_ordering; }
 384   void set_method_ordering(Array<int>* m) { _method_ordering = m; }
 385   void copy_method_ordering(const intArray* m, TRAPS);
 386 
 387   // default_methods
 388   Array<Method*>* default_methods() const  { return _default_methods; }
 389   void set_default_methods(Array<Method*>* a) { _default_methods = a; }
 390 
 391   // default method vtable_indices
 392   Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
 393   void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
 394   Array<int>* create_new_default_vtable_indices(int len, TRAPS);
 395 
 396   // interfaces
 397   Array<Klass*>* local_interfaces() const          { return _local_interfaces; }
 398   void set_local_interfaces(Array<Klass*>* a)      {
 399     guarantee(_local_interfaces == NULL || a == NULL, "Just checking");
 400     _local_interfaces = a; }
 401 
 402   Array<Klass*>* transitive_interfaces() const     { return _transitive_interfaces; }
 403   void set_transitive_interfaces(Array<Klass*>* a) {
 404     guarantee(_transitive_interfaces == NULL || a == NULL, "Just checking");
 405     _transitive_interfaces = a;
 406   }
 407 
 408  private:
 409   friend class fieldDescriptor;
 410   FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }
 411 
 412  public:
 413   int     field_offset      (int index) const { return field(index)->offset(); }
 414   int     field_access_flags(int index) const { return field(index)->access_flags(); }
 415   Symbol* field_name        (int index) const { return field(index)->name(constants()); }
 416   Symbol* field_signature   (int index) const { return field(index)->signature(constants()); }
 417 
 418   // Number of Java declared fields
 419   int java_fields_count() const           { return (int)_java_fields_count; }
 420 
 421   Array<u2>* fields() const            { return _fields; }
 422   void set_fields(Array<u2>* f, u2 java_fields_count) {
 423     guarantee(_fields == NULL || f == NULL, "Just checking");
 424     _fields = f;
 425     _java_fields_count = java_fields_count;
 426   }
 427 
 428   // inner classes
 429   Array<u2>* inner_classes() const       { return _inner_classes; }
 430   void set_inner_classes(Array<u2>* f)   { _inner_classes = f; }
 431 
 432   enum InnerClassAttributeOffset {
 433     // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
 434     inner_class_inner_class_info_offset = 0,
 435     inner_class_outer_class_info_offset = 1,
 436     inner_class_inner_name_offset = 2,
 437     inner_class_access_flags_offset = 3,
 438     inner_class_next_offset = 4
 439   };
 440 
 441   enum EnclosingMethodAttributeOffset {
 442     enclosing_method_class_index_offset = 0,
 443     enclosing_method_method_index_offset = 1,
 444     enclosing_method_attribute_size = 2
 445   };
 446 
 447   // method override check
 448   bool is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS);
 449 
 450   // package
 451   PackageEntry* package() const     { return _package_entry; }
 452   ModuleEntry* module() const;
 453   bool in_unnamed_package() const   { return (_package_entry == NULL); }
 454   void set_package(PackageEntry* p) { _package_entry = p; }
 455   void set_package(ClassLoaderData* loader_data, TRAPS);
 456   bool is_same_class_package(const Klass* class2) const;
 457   bool is_same_class_package(oop classloader2, const Symbol* classname2) const;
 458   static bool is_same_class_package(oop class_loader1,
 459                                     const Symbol* class_name1,
 460                                     oop class_loader2,
 461                                     const Symbol* class_name2);
 462 
 463   // find an enclosing class
 464   InstanceKlass* compute_enclosing_class(bool* inner_is_member, TRAPS) const;
 465 
 466   // Find InnerClasses attribute and return outer_class_info_index & inner_name_index.
 467   bool find_inner_classes_attr(int* ooff, int* noff, TRAPS) const;
 468 
 469  private:
 470   // Check prohibited package ("java/" only loadable by boot or platform loaders)
 471   static void check_prohibited_package(Symbol* class_name,
 472                                        Handle class_loader,
 473                                        TRAPS);
 474  public:
 475   // tell if two classes have the same enclosing class (at package level)
 476   bool is_same_package_member(const Klass* class2, TRAPS) const;
 477 
 478   // initialization state
 479   bool is_loaded() const                   { return _init_state >= loaded; }
 480   bool is_linked() const                   { return _init_state >= linked; }
 481   bool is_initialized() const              { return _init_state == fully_initialized; }
 482   bool is_not_initialized() const          { return _init_state <  being_initialized; }
 483   bool is_being_initialized() const        { return _init_state == being_initialized; }
 484   bool is_in_error_state() const           { return _init_state == initialization_error; }
 485   bool is_reentrant_initialization(Thread *thread)  { return thread == _init_thread; }
 486   ClassState  init_state()                 { return (ClassState)_init_state; }
 487   bool is_rewritten() const                { return (_misc_flags & _misc_rewritten) != 0; }
 488 
 489   // defineClass specified verification
 490   bool should_verify_class() const         {
 491     return (_misc_flags & _misc_should_verify_class) != 0;
 492   }
 493   void set_should_verify_class(bool value) {
 494     if (value) {
 495       _misc_flags |= _misc_should_verify_class;
 496     } else {
 497       _misc_flags &= ~_misc_should_verify_class;
 498     }
 499   }
 500 
 501   // marking
 502   bool is_marked_dependent() const         { return _is_marked_dependent; }
 503   void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
 504 
 505   // initialization (virtuals from Klass)
 506   bool should_be_initialized() const;  // means that initialize should be called
 507   void initialize(TRAPS);
 508   void link_class(TRAPS);
 509   bool link_class_or_fail(TRAPS); // returns false on failure
 510   void unlink_class();
 511   void rewrite_class(TRAPS);
 512   void link_methods(TRAPS);
 513   Method* class_initializer() const;
 514 
 515   // set the class to initialized if no static initializer is present
 516   void eager_initialize(Thread *thread);
 517 
 518   // reference type
 519   ReferenceType reference_type() const     { return (ReferenceType)_reference_type; }
 520   void set_reference_type(ReferenceType t) {
 521     assert(t == (u1)t, "overflow");
 522     _reference_type = (u1)t;
 523   }
 524 
 525   static ByteSize reference_type_offset() { return in_ByteSize(offset_of(InstanceKlass, _reference_type)); }
 526 
 527   // find local field, returns true if found
 528   bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 529   // find field in direct superinterfaces, returns the interface in which the field is defined
 530   Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 531   // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 532   Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 533   // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 534   Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
 535 
 536   // find a non-static or static field given its offset within the class.
 537   bool contains_field_offset(int offset) {
 538     return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
 539   }
 540 
 541   bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 542   bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 543 
 544   // find a local method (returns NULL if not found)
 545   Method* find_method(const Symbol* name, const Symbol* signature) const;
 546   static Method* find_method(const Array<Method*>* methods,
 547                              const Symbol* name,
 548                              const Symbol* signature);
 549 
 550   // find a local method, but skip static methods
 551   Method* find_instance_method(const Symbol* name, const Symbol* signature) const;
 552   static Method* find_instance_method(const Array<Method*>* methods,
 553                                       const Symbol* name,
 554                                       const Symbol* signature);
 555 
 556   // find a local method (returns NULL if not found)
 557   Method* find_local_method(const Symbol* name,
 558                             const Symbol* signature,
 559                             OverpassLookupMode overpass_mode,
 560                             StaticLookupMode static_mode,
 561                             PrivateLookupMode private_mode) const;
 562 
 563   // find a local method from given methods array (returns NULL if not found)
 564   static Method* find_local_method(const Array<Method*>* methods,
 565                                    const Symbol* name,
 566                                    const Symbol* signature,
 567                                    OverpassLookupMode overpass_mode,
 568                                    StaticLookupMode static_mode,
 569                                    PrivateLookupMode private_mode);
 570 
 571   // find a local method index in methods or default_methods (returns -1 if not found)
 572   static int find_method_index(const Array<Method*>* methods,
 573                                const Symbol* name,
 574                                const Symbol* signature,
 575                                OverpassLookupMode overpass_mode,
 576                                StaticLookupMode static_mode,
 577                                PrivateLookupMode private_mode);
 578 
 579   // lookup operation (returns NULL if not found)
 580   Method* uncached_lookup_method(const Symbol* name,
 581                                  const Symbol* signature,
 582                                  OverpassLookupMode overpass_mode) const;
 583 
 584   // lookup a method in all the interfaces that this class implements
 585   // (returns NULL if not found)
 586   Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, DefaultsLookupMode defaults_mode) const;
 587 
 588   // lookup a method in local defaults then in all interfaces
 589   // (returns NULL if not found)
 590   Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
 591 
 592   // Find method indices by name.  If a method with the specified name is
 593   // found the index to the first method is returned, and 'end' is filled in
 594   // with the index of first non-name-matching method.  If no method is found
 595   // -1 is returned.
 596   int find_method_by_name(const Symbol* name, int* end) const;
 597   static int find_method_by_name(const Array<Method*>* methods,
 598                                  const Symbol* name, int* end);
 599 
 600   // constant pool
 601   ConstantPool* constants() const        { return _constants; }
 602   void set_constants(ConstantPool* c)    { _constants = c; }
 603 
 604   // protection domain
 605   oop protection_domain() const;
 606 
 607   // signers
 608   objArrayOop signers() const;
 609 
 610   // host class
 611   InstanceKlass* host_klass() const              {
 612     InstanceKlass** hk = adr_host_klass();
 613     if (hk == NULL) {
 614       return NULL;
 615     } else {
 616       assert(*hk != NULL, "host klass should always be set if the address is not null");
 617       return *hk;
 618     }
 619   }
 620   void set_host_klass(const InstanceKlass* host) {
 621     assert(is_anonymous(), "not anonymous");
 622     const InstanceKlass** addr = (const InstanceKlass **)adr_host_klass();
 623     assert(addr != NULL, "no reversed space");
 624     if (addr != NULL) {
 625       *addr = host;
 626     }
 627   }
 628   bool is_anonymous() const                {
 629     return (_misc_flags & _misc_is_anonymous) != 0;
 630   }
 631   void set_is_anonymous(bool value)        {
 632     if (value) {
 633       _misc_flags |= _misc_is_anonymous;
 634     } else {
 635       _misc_flags &= ~_misc_is_anonymous;
 636     }
 637   }
 638 
 639   // Oop that keeps the metadata for this class from being unloaded
 640   // in places where the metadata is stored in other places, like nmethods
 641   oop klass_holder() const {
 642     return is_anonymous() ? java_mirror() : class_loader();
 643   }
 644 
 645   bool is_contended() const                {
 646     return (_misc_flags & _misc_is_contended) != 0;
 647   }
 648   void set_is_contended(bool value)        {
 649     if (value) {
 650       _misc_flags |= _misc_is_contended;
 651     } else {
 652       _misc_flags &= ~_misc_is_contended;
 653     }
 654   }
 655 
 656   // source file name
 657   Symbol* source_file_name() const               {
 658     return (_source_file_name_index == 0) ?
 659       (Symbol*)NULL : _constants->symbol_at(_source_file_name_index);
 660   }
 661   u2 source_file_name_index() const              {
 662     return _source_file_name_index;
 663   }
 664   void set_source_file_name_index(u2 sourcefile_index) {
 665     _source_file_name_index = sourcefile_index;
 666   }
 667 
 668   // minor and major version numbers of class file
 669   u2 minor_version() const                 { return _minor_version; }
 670   void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
 671   u2 major_version() const                 { return _major_version; }
 672   void set_major_version(u2 major_version) { _major_version = 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   // symbol unloading support (refcount already added)
 679   Symbol* array_name()                     { return _array_name; }
 680   void set_array_name(Symbol* name)        { assert(_array_name == NULL  || name == NULL, "name already created"); _array_name = name; }
 681 
 682   // nonstatic oop-map blocks
 683   static int nonstatic_oop_map_size(unsigned int oop_map_count) {
 684     return oop_map_count * OopMapBlock::size_in_words();
 685   }
 686   unsigned int nonstatic_oop_map_count() const {
 687     return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
 688   }
 689   int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
 690   void set_nonstatic_oop_map_size(int words) {
 691     _nonstatic_oop_map_size = words;
 692   }
 693 
 694 #if INCLUDE_JVMTI
 695   // Redefinition locking.  Class can only be redefined by one thread at a time.
 696   bool is_being_redefined() const          { return _is_being_redefined; }
 697   void set_is_being_redefined(bool value)  { _is_being_redefined = value; }
 698 
 699   // RedefineClasses() support for previous versions:
 700   void add_previous_version(InstanceKlass* ik, int emcp_method_count);
 701   void purge_previous_version_list();
 702 
 703   InstanceKlass* previous_versions() const { return _previous_versions; }
 704 #else
 705   InstanceKlass* previous_versions() const { return NULL; }
 706 #endif
 707 
 708   InstanceKlass* get_klass_version(int version) {
 709     for (InstanceKlass* ik = this; ik != NULL; ik = ik->previous_versions()) {
 710       if (ik->constants()->version() == version) {
 711         return ik;
 712       }
 713     }
 714     return NULL;
 715   }
 716 
 717   bool has_been_redefined() const {
 718     return (_misc_flags & _misc_has_been_redefined) != 0;
 719   }
 720   void set_has_been_redefined() {
 721     _misc_flags |= _misc_has_been_redefined;
 722   }
 723 
 724   bool has_passed_fingerprint_check() const {
 725     return (_misc_flags & _misc_has_passed_fingerprint_check) != 0;
 726   }
 727   void set_has_passed_fingerprint_check(bool b) {
 728     if (b) {
 729       _misc_flags |= _misc_has_passed_fingerprint_check;
 730     } else {
 731       _misc_flags &= ~_misc_has_passed_fingerprint_check;
 732     }
 733   }
 734   bool supers_have_passed_fingerprint_checks();
 735 
 736   static bool should_store_fingerprint();
 737   bool has_stored_fingerprint() const;
 738   uint64_t get_stored_fingerprint() const;
 739   void store_fingerprint(uint64_t fingerprint);
 740 
 741   bool is_scratch_class() const {
 742     return (_misc_flags & _misc_is_scratch_class) != 0;
 743   }
 744 
 745   void set_is_scratch_class() {
 746     _misc_flags |= _misc_is_scratch_class;
 747   }
 748 
 749   bool has_resolved_methods() const {
 750     return (_misc_flags & _misc_has_resolved_methods) != 0;
 751   }
 752 
 753   void set_has_resolved_methods() {
 754     _misc_flags |= _misc_has_resolved_methods;
 755   }
 756 private:
 757 
 758   void set_kind(unsigned kind) {
 759     assert(kind <= _misc_kind_field_mask, "Invalid InstanceKlass kind");
 760     unsigned fmask = _misc_kind_field_mask << _misc_kind_field_pos;
 761     unsigned flags = _misc_flags & ~fmask;
 762     _misc_flags = (flags | (kind << _misc_kind_field_pos));
 763   }
 764 
 765   bool is_kind(unsigned desired) const {
 766     unsigned kind = (_misc_flags >> _misc_kind_field_pos) & _misc_kind_field_mask;
 767     return kind == desired;
 768   }
 769 
 770 public:
 771 
 772   // Other is anything that is not one of the more specialized kinds of InstanceKlass.
 773   bool is_other_instance_klass() const        { return is_kind(_misc_kind_other); }
 774   bool is_reference_instance_klass() const    { return is_kind(_misc_kind_reference); }
 775   bool is_mirror_instance_klass() const       { return is_kind(_misc_kind_mirror); }
 776   bool is_class_loader_instance_klass() const { return is_kind(_misc_kind_class_loader); }
 777 
 778 #if INCLUDE_JVMTI
 779 
 780   void init_previous_versions() {
 781     _previous_versions = NULL;
 782   }
 783 
 784  private:
 785   static bool  _has_previous_versions;
 786  public:
 787   static void purge_previous_versions(InstanceKlass* ik) {
 788     if (ik->has_been_redefined()) {
 789       ik->purge_previous_version_list();
 790     }
 791   }
 792 
 793   static bool has_previous_versions_and_reset();
 794 
 795   // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
 796   void set_cached_class_file(JvmtiCachedClassFileData *data) {
 797     _cached_class_file = data;
 798   }
 799   JvmtiCachedClassFileData * get_cached_class_file();
 800   jint get_cached_class_file_len();
 801   unsigned char * get_cached_class_file_bytes();
 802 
 803   // JVMTI: Support for caching of field indices, types, and offsets
 804   void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
 805     _jvmti_cached_class_field_map = descriptor;
 806   }
 807   JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
 808     return _jvmti_cached_class_field_map;
 809   }
 810 
 811 #if INCLUDE_CDS
 812   void set_archived_class_data(JvmtiCachedClassFileData* data) {
 813     _cached_class_file = data;
 814   }
 815 
 816   JvmtiCachedClassFileData * get_archived_class_data();
 817 #endif // INCLUDE_CDS
 818 #else // INCLUDE_JVMTI
 819 
 820   static void purge_previous_versions(InstanceKlass* ik) { return; };
 821   static bool has_previous_versions_and_reset() { return false; }
 822 
 823   void set_cached_class_file(JvmtiCachedClassFileData *data) {
 824     assert(data == NULL, "unexpected call with JVMTI disabled");
 825   }
 826   JvmtiCachedClassFileData * get_cached_class_file() { return (JvmtiCachedClassFileData *)NULL; }
 827 
 828 #endif // INCLUDE_JVMTI
 829 
 830   bool has_nonstatic_concrete_methods() const {
 831     return (_misc_flags & _misc_has_nonstatic_concrete_methods) != 0;
 832   }
 833   void set_has_nonstatic_concrete_methods(bool b) {
 834     if (b) {
 835       _misc_flags |= _misc_has_nonstatic_concrete_methods;
 836     } else {
 837       _misc_flags &= ~_misc_has_nonstatic_concrete_methods;
 838     }
 839   }
 840 
 841   bool declares_nonstatic_concrete_methods() const {
 842     return (_misc_flags & _misc_declares_nonstatic_concrete_methods) != 0;
 843   }
 844   void set_declares_nonstatic_concrete_methods(bool b) {
 845     if (b) {
 846       _misc_flags |= _misc_declares_nonstatic_concrete_methods;
 847     } else {
 848       _misc_flags &= ~_misc_declares_nonstatic_concrete_methods;
 849     }
 850   }
 851 
 852   // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
 853   inline u2 next_method_idnum();
 854   void set_initial_method_idnum(u2 value)             { _idnum_allocated_count = value; }
 855 
 856   // generics support
 857   Symbol* generic_signature() const                   {
 858     return (_generic_signature_index == 0) ?
 859       (Symbol*)NULL : _constants->symbol_at(_generic_signature_index);
 860   }
 861   u2 generic_signature_index() const                  {
 862     return _generic_signature_index;
 863   }
 864   void set_generic_signature_index(u2 sig_index)      {
 865     _generic_signature_index = sig_index;
 866   }
 867 
 868   u2 enclosing_method_data(int offset) const;
 869   u2 enclosing_method_class_index() const {
 870     return enclosing_method_data(enclosing_method_class_index_offset);
 871   }
 872   u2 enclosing_method_method_index() {
 873     return enclosing_method_data(enclosing_method_method_index_offset);
 874   }
 875   void set_enclosing_method_indices(u2 class_index,
 876                                     u2 method_index);
 877 
 878   // jmethodID support
 879   jmethodID get_jmethod_id(const methodHandle& method_h);
 880   jmethodID get_jmethod_id_fetch_or_update(size_t idnum,
 881                      jmethodID new_id, jmethodID* new_jmeths,
 882                      jmethodID* to_dealloc_id_p,
 883                      jmethodID** to_dealloc_jmeths_p);
 884   static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum,
 885                 size_t *length_p, jmethodID* id_p);
 886   void ensure_space_for_methodids(int start_offset = 0);
 887   jmethodID jmethod_id_or_null(Method* method);
 888 
 889   // annotations support
 890   Annotations* annotations() const          { return _annotations; }
 891   void set_annotations(Annotations* anno)   { _annotations = anno; }
 892 
 893   AnnotationArray* class_annotations() const {
 894     return (_annotations != NULL) ? _annotations->class_annotations() : NULL;
 895   }
 896   Array<AnnotationArray*>* fields_annotations() const {
 897     return (_annotations != NULL) ? _annotations->fields_annotations() : NULL;
 898   }
 899   AnnotationArray* class_type_annotations() const {
 900     return (_annotations != NULL) ? _annotations->class_type_annotations() : NULL;
 901   }
 902   Array<AnnotationArray*>* fields_type_annotations() const {
 903     return (_annotations != NULL) ? _annotations->fields_type_annotations() : NULL;
 904   }
 905   // allocation
 906   instanceOop allocate_instance(TRAPS);
 907 
 908   // additional member function to return a handle
 909   instanceHandle allocate_instance_handle(TRAPS)      { return instanceHandle(THREAD, allocate_instance(THREAD)); }
 910 
 911   objArrayOop allocate_objArray(int n, int length, TRAPS);
 912   // Helper function
 913   static instanceOop register_finalizer(instanceOop i, TRAPS);
 914 
 915   // Check whether reflection/jni/jvm code is allowed to instantiate this class;
 916   // if not, throw either an Error or an Exception.
 917   virtual void check_valid_for_instantiation(bool throwError, TRAPS);
 918 
 919   // initialization
 920   void call_class_initializer(TRAPS);
 921   void set_initialization_state_and_notify(ClassState state, TRAPS);
 922 
 923   // OopMapCache support
 924   OopMapCache* oop_map_cache()               { return _oop_map_cache; }
 925   void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
 926   void mask_for(const methodHandle& method, int bci, InterpreterOopMap* entry);
 927 
 928   // JNI identifier support (for static fields - for jni performance)
 929   JNIid* jni_ids()                               { return _jni_ids; }
 930   void set_jni_ids(JNIid* ids)                   { _jni_ids = ids; }
 931   JNIid* jni_id_for(int offset);
 932 
 933   // maintenance of deoptimization dependencies
 934   inline DependencyContext dependencies();
 935   int  mark_dependent_nmethods(KlassDepChange& changes);
 936   void add_dependent_nmethod(nmethod* nm);
 937   void remove_dependent_nmethod(nmethod* nm, bool delete_immediately);
 938 
 939   // On-stack replacement support
 940   nmethod* osr_nmethods_head() const         { return _osr_nmethods_head; };
 941   void set_osr_nmethods_head(nmethod* h)     { _osr_nmethods_head = h; };
 942   void add_osr_nmethod(nmethod* n);
 943   bool remove_osr_nmethod(nmethod* n);
 944   int mark_osr_nmethods(const Method* m);
 945   nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
 946 
 947 #if INCLUDE_JVMTI
 948   // Breakpoint support (see methods on Method* for details)
 949   BreakpointInfo* breakpoints() const       { return _breakpoints; };
 950   void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
 951 #endif
 952 
 953   // support for stub routines
 954   static ByteSize init_state_offset()  { return in_ByteSize(offset_of(InstanceKlass, _init_state)); }
 955   TRACE_DEFINE_KLASS_TRACE_ID_OFFSET;
 956   static ByteSize init_thread_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_thread)); }
 957 
 958   // subclass/subinterface checks
 959   bool implements_interface(Klass* k) const;
 960   bool is_same_or_direct_interface(Klass* k) const;
 961 
 962 #ifdef ASSERT
 963   // check whether this class or one of its superclasses was redefined
 964   bool has_redefined_this_or_super() const;
 965 #endif
 966 
 967   // Access to the implementor of an interface.
 968   Klass* implementor() const
 969   {
 970     Klass** k = adr_implementor();
 971     if (k == NULL) {
 972       return NULL;
 973     } else {
 974       return *k;
 975     }
 976   }
 977 
 978   void set_implementor(Klass* k) {
 979     assert(is_interface(), "not interface");
 980     Klass** addr = adr_implementor();
 981     assert(addr != NULL, "null addr");
 982     if (addr != NULL) {
 983       *addr = k;
 984     }
 985   }
 986 
 987   int  nof_implementors() const       {
 988     Klass* k = implementor();
 989     if (k == NULL) {
 990       return 0;
 991     } else if (k != this) {
 992       return 1;
 993     } else {
 994       return 2;
 995     }
 996   }
 997 
 998   void add_implementor(Klass* k);  // k is a new class that implements this interface
 999   void init_implementor();           // initialize
1000 
1001   // link this class into the implementors list of every interface it implements
1002   void process_interfaces(Thread *thread);
1003 
1004   // virtual operations from Klass
1005   bool is_leaf_class() const               { return _subklass == NULL; }
1006   GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
1007   bool compute_is_subtype_of(Klass* k);
1008   bool can_be_primary_super_slow() const;
1009   int oop_size(oop obj)  const             { return size_helper(); }
1010   // slow because it's a virtual call and used for verifying the layout_helper.
1011   // Using the layout_helper bits, we can call is_instance_klass without a virtual call.
1012   DEBUG_ONLY(bool is_instance_klass_slow() const      { return true; })
1013 
1014   // Iterators
1015   void do_local_static_fields(FieldClosure* cl);
1016   void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
1017   void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
1018 
1019   void methods_do(void f(Method* method));
1020   void array_klasses_do(void f(Klass* k));
1021   void array_klasses_do(void f(Klass* k, TRAPS), TRAPS);
1022   bool super_types_do(SuperTypeClosure* blk);
1023 
1024   static InstanceKlass* cast(Klass* k) {
1025     return const_cast<InstanceKlass*>(cast(const_cast<const Klass*>(k)));
1026   }
1027 
1028   static const InstanceKlass* cast(const Klass* k) {
1029     assert(k != NULL, "k should not be null");
1030     assert(k->is_instance_klass(), "cast to InstanceKlass");
1031     return static_cast<const InstanceKlass*>(k);
1032   }
1033 
1034   InstanceKlass* java_super() const {
1035     return (super() == NULL) ? NULL : cast(super());
1036   }
1037 
1038   // Sizing (in words)
1039   static int header_size()            { return sizeof(InstanceKlass)/wordSize; }
1040 
1041   static int size(int vtable_length, int itable_length,
1042                   int nonstatic_oop_map_size,
1043                   bool is_interface, bool is_anonymous, bool has_stored_fingerprint) {
1044     return align_metadata_size(header_size() +
1045            vtable_length +
1046            itable_length +
1047            nonstatic_oop_map_size +
1048            (is_interface ? (int)sizeof(Klass*)/wordSize : 0) +
1049            (is_anonymous ? (int)sizeof(Klass*)/wordSize : 0) +
1050            (has_stored_fingerprint ? (int)sizeof(uint64_t*)/wordSize : 0));
1051   }
1052   int size() const                    { return size(vtable_length(),
1053                                                itable_length(),
1054                                                nonstatic_oop_map_size(),
1055                                                is_interface(),
1056                                                is_anonymous(),
1057                                                has_stored_fingerprint());
1058   }
1059 #if INCLUDE_SERVICES
1060   virtual void collect_statistics(KlassSizeStats *sz) const;
1061 #endif
1062 
1063   intptr_t* start_of_itable()   const { return (intptr_t*)start_of_vtable() + vtable_length(); }
1064   intptr_t* end_of_itable()     const { return start_of_itable() + itable_length(); }
1065 
1066   int  itable_offset_in_words() const { return start_of_itable() - (intptr_t*)this; }
1067 
1068   address static_field_addr(int offset);
1069 
1070   OopMapBlock* start_of_nonstatic_oop_maps() const {
1071     return (OopMapBlock*)(start_of_itable() + itable_length());
1072   }
1073 
1074   Klass** end_of_nonstatic_oop_maps() const {
1075     return (Klass**)(start_of_nonstatic_oop_maps() +
1076                      nonstatic_oop_map_count());
1077   }
1078 
1079   Klass** adr_implementor() const {
1080     if (is_interface()) {
1081       return (Klass**)end_of_nonstatic_oop_maps();
1082     } else {
1083       return NULL;
1084     }
1085   };
1086 
1087   InstanceKlass** adr_host_klass() const {
1088     if (is_anonymous()) {
1089       InstanceKlass** adr_impl = (InstanceKlass **)adr_implementor();
1090       if (adr_impl != NULL) {
1091         return adr_impl + 1;
1092       } else {
1093         return (InstanceKlass **)end_of_nonstatic_oop_maps();
1094       }
1095     } else {
1096       return NULL;
1097     }
1098   }
1099 
1100   address adr_fingerprint() const {
1101     if (has_stored_fingerprint()) {
1102       InstanceKlass** adr_host = adr_host_klass();
1103       if (adr_host != NULL) {
1104         return (address)(adr_host + 1);
1105       }
1106 
1107       Klass** adr_impl = adr_implementor();
1108       if (adr_impl != NULL) {
1109         return (address)(adr_impl + 1);
1110       }
1111 
1112       return (address)end_of_nonstatic_oop_maps();
1113     } else {
1114       return NULL;
1115     }
1116   }
1117 
1118   // Use this to return the size of an instance in heap words:
1119   int size_helper() const {
1120     return layout_helper_to_size_helper(layout_helper());
1121   }
1122 
1123   // This bit is initialized in classFileParser.cpp.
1124   // It is false under any of the following conditions:
1125   //  - the class is abstract (including any interface)
1126   //  - the class has a finalizer (if !RegisterFinalizersAtInit)
1127   //  - the class size is larger than FastAllocateSizeLimit
1128   //  - the class is java/lang/Class, which cannot be allocated directly
1129   bool can_be_fastpath_allocated() const {
1130     return !layout_helper_needs_slow_path(layout_helper());
1131   }
1132 
1133   // Java itable
1134   klassItable itable() const;        // return klassItable wrapper
1135   Method* method_at_itable(Klass* holder, int index, TRAPS);
1136 
1137 #if INCLUDE_JVMTI
1138   void adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed);
1139 #endif // INCLUDE_JVMTI
1140 
1141   void clean_weak_instanceklass_links(BoolObjectClosure* is_alive);
1142   void clean_implementors_list(BoolObjectClosure* is_alive);
1143   void clean_method_data(BoolObjectClosure* is_alive);
1144 
1145   // Explicit metaspace deallocation of fields
1146   // For RedefineClasses and class file parsing errors, we need to deallocate
1147   // instanceKlasses and the metadata they point to.
1148   void deallocate_contents(ClassLoaderData* loader_data);
1149   static void deallocate_methods(ClassLoaderData* loader_data,
1150                                  Array<Method*>* methods);
1151   void static deallocate_interfaces(ClassLoaderData* loader_data,
1152                                     const Klass* super_klass,
1153                                     Array<Klass*>* local_interfaces,
1154                                     Array<Klass*>* transitive_interfaces);
1155 
1156   // The constant pool is on stack if any of the methods are executing or
1157   // referenced by handles.
1158   bool on_stack() const { return _constants->on_stack(); }
1159 
1160   // callbacks for actions during class unloading
1161   static void notify_unload_class(InstanceKlass* ik);
1162   static void release_C_heap_structures(InstanceKlass* ik);
1163 
1164   // Naming
1165   const char* signature_name() const;
1166   static Symbol* package_from_name(const Symbol* name, TRAPS);
1167 
1168   // GC specific object visitors
1169   //
1170 #if INCLUDE_ALL_GCS
1171   // Parallel Scavenge
1172   void oop_ps_push_contents(  oop obj, PSPromotionManager* pm);
1173   // Parallel Compact
1174   void oop_pc_follow_contents(oop obj, ParCompactionManager* cm);
1175   void oop_pc_update_pointers(oop obj, ParCompactionManager* cm);
1176 #endif
1177 
1178   // Oop fields (and metadata) iterators
1179   //  [nv = true]  Use non-virtual calls to do_oop_nv.
1180   //  [nv = false] Use virtual calls to do_oop.
1181   //
1182   // The InstanceKlass iterators also visits the Object's klass.
1183 
1184   // Forward iteration
1185  public:
1186   // Iterate over all oop fields in the oop maps.
1187   template <bool nv, class OopClosureType>
1188   inline void oop_oop_iterate_oop_maps(oop obj, OopClosureType* closure);
1189 
1190  protected:
1191   // Iterate over all oop fields and metadata.
1192   template <bool nv, class OopClosureType>
1193   inline int oop_oop_iterate(oop obj, OopClosureType* closure);
1194 
1195  private:
1196   // Iterate over all oop fields in the oop maps.
1197   // Specialized for [T = oop] or [T = narrowOop].
1198   template <bool nv, typename T, class OopClosureType>
1199   inline void oop_oop_iterate_oop_maps_specialized(oop obj, OopClosureType* closure);
1200 
1201   // Iterate over all oop fields in one oop map.
1202   template <bool nv, typename T, class OopClosureType>
1203   inline void oop_oop_iterate_oop_map(OopMapBlock* map, oop obj, OopClosureType* closure);
1204 
1205 
1206   // Reverse iteration
1207 #if INCLUDE_ALL_GCS
1208  public:
1209   // Iterate over all oop fields in the oop maps.
1210   template <bool nv, class OopClosureType>
1211   inline void oop_oop_iterate_oop_maps_reverse(oop obj, OopClosureType* closure);
1212 
1213  protected:
1214   // Iterate over all oop fields and metadata.
1215   template <bool nv, class OopClosureType>
1216   inline int oop_oop_iterate_reverse(oop obj, OopClosureType* closure);
1217 
1218  private:
1219   // Iterate over all oop fields in the oop maps.
1220   // Specialized for [T = oop] or [T = narrowOop].
1221   template <bool nv, typename T, class OopClosureType>
1222   inline void oop_oop_iterate_oop_maps_specialized_reverse(oop obj, OopClosureType* closure);
1223 
1224   // Iterate over all oop fields in one oop map.
1225   template <bool nv, typename T, class OopClosureType>
1226   inline void oop_oop_iterate_oop_map_reverse(OopMapBlock* map, oop obj, OopClosureType* closure);
1227 #endif
1228 
1229 
1230   // Bounded range iteration
1231  public:
1232   // Iterate over all oop fields in the oop maps.
1233   template <bool nv, class OopClosureType>
1234   inline void oop_oop_iterate_oop_maps_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1235 
1236  protected:
1237   // Iterate over all oop fields and metadata.
1238   template <bool nv, class OopClosureType>
1239   inline int oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1240 
1241  private:
1242   // Iterate over all oop fields in the oop maps.
1243   // Specialized for [T = oop] or [T = narrowOop].
1244   template <bool nv, typename T, class OopClosureType>
1245   inline void oop_oop_iterate_oop_maps_specialized_bounded(oop obj, OopClosureType* closure, MemRegion mr);
1246 
1247   // Iterate over all oop fields in one oop map.
1248   template <bool nv, typename T, class OopClosureType>
1249   inline void oop_oop_iterate_oop_map_bounded(OopMapBlock* map, oop obj, OopClosureType* closure, MemRegion mr);
1250 
1251 
1252  public:
1253 
1254   ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_OOP_ITERATE_DECL)
1255   ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_OOP_ITERATE_DECL)
1256 
1257 #if INCLUDE_ALL_GCS
1258   ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_OOP_ITERATE_DECL_BACKWARDS)
1259   ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_OOP_ITERATE_DECL_BACKWARDS)
1260 #endif // INCLUDE_ALL_GCS
1261 
1262   u2 idnum_allocated_count() const      { return _idnum_allocated_count; }
1263 
1264 public:
1265   void set_in_error_state() {
1266     assert(DumpSharedSpaces, "only call this when dumping archive");
1267     _init_state = initialization_error;
1268   }
1269   bool check_sharing_error_state();
1270 
1271 private:
1272   // initialization state
1273 #ifdef ASSERT
1274   void set_init_state(ClassState state);
1275 #else
1276   void set_init_state(ClassState state) { _init_state = (u1)state; }
1277 #endif
1278   void set_rewritten()                  { _misc_flags |= _misc_rewritten; }
1279   void set_init_thread(Thread *thread)  { _init_thread = thread; }
1280 
1281   // The RedefineClasses() API can cause new method idnums to be needed
1282   // which will cause the caches to grow. Safety requires different
1283   // cache management logic if the caches can grow instead of just
1284   // going from NULL to non-NULL.
1285   bool idnum_can_increment() const      { return has_been_redefined(); }
1286   inline jmethodID* methods_jmethod_ids_acquire() const;
1287   inline void release_set_methods_jmethod_ids(jmethodID* jmeths);
1288 
1289   // Lock during initialization
1290 public:
1291   // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1292   // Must be one per class and it has to be a VM internal object so java code
1293   // cannot lock it (like the mirror).
1294   // It has to be an object not a Mutex because it's held through java calls.
1295   oop init_lock() const;
1296 private:
1297   void fence_and_clear_init_lock();
1298 
1299   bool link_class_impl                           (bool throw_verifyerror, TRAPS);
1300   bool verify_code                               (bool throw_verifyerror, TRAPS);
1301   void initialize_impl                           (TRAPS);
1302   void initialize_super_interfaces               (TRAPS);
1303   void eager_initialize_impl                     ();
1304   /* jni_id_for_impl for jfieldID only */
1305   JNIid* jni_id_for_impl                         (int offset);
1306 
1307   // Returns the array class for the n'th dimension
1308   Klass* array_klass_impl(bool or_null, int n, TRAPS);
1309 
1310   // Returns the array class with this class as element type
1311   Klass* array_klass_impl(bool or_null, TRAPS);
1312 
1313   // find a local method (returns NULL if not found)
1314   Method* find_method_impl(const Symbol* name,
1315                            const Symbol* signature,
1316                            OverpassLookupMode overpass_mode,
1317                            StaticLookupMode static_mode,
1318                            PrivateLookupMode private_mode) const;
1319 
1320   static Method* find_method_impl(const Array<Method*>* methods,
1321                                   const Symbol* name,
1322                                   const Symbol* signature,
1323                                   OverpassLookupMode overpass_mode,
1324                                   StaticLookupMode static_mode,
1325                                   PrivateLookupMode private_mode);
1326 
1327   // Free CHeap allocated fields.
1328   void release_C_heap_structures();
1329 
1330 #if INCLUDE_JVMTI
1331   // RedefineClasses support
1332   void link_previous_versions(InstanceKlass* pv) { _previous_versions = pv; }
1333   void mark_newly_obsolete_methods(Array<Method*>* old_methods, int emcp_method_count);
1334 #endif
1335 public:
1336   // CDS support - remove and restore oops from metadata. Oops are not shared.
1337   virtual void remove_unshareable_info();
1338   virtual void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS);
1339 
1340   // jvm support
1341   jint compute_modifier_flags(TRAPS) const;
1342 
1343 public:
1344   // JVMTI support
1345   jint jvmti_class_status() const;
1346 
1347  public:
1348   // Printing
1349 #ifndef PRODUCT
1350   void print_on(outputStream* st) const;
1351 #endif
1352   void print_value_on(outputStream* st) const;
1353 
1354   void oop_print_value_on(oop obj, outputStream* st);
1355 
1356 #ifndef PRODUCT
1357   void oop_print_on      (oop obj, outputStream* st);
1358 
1359   void print_dependent_nmethods(bool verbose = false);
1360   bool is_dependent_nmethod(nmethod* nm);
1361 #endif
1362 
1363   const char* internal_name() const;
1364 
1365   // Verification
1366   void verify_on(outputStream* st);
1367 
1368   void oop_verify_on(oop obj, outputStream* st);
1369 
1370   // Logging
1371   void print_class_load_logging(ClassLoaderData* loader_data,
1372                                 const char* module_name,
1373                                 const ClassFileStream* cfs) const;
1374 };
1375 
1376 // for adding methods
1377 // UNSET_IDNUM return means no more ids available
1378 inline u2 InstanceKlass::next_method_idnum() {
1379   if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1380     return ConstMethod::UNSET_IDNUM; // no more ids available
1381   } else {
1382     return _idnum_allocated_count++;
1383   }
1384 }
1385 
1386 
1387 /* JNIid class for jfieldIDs only */
1388 class JNIid: public CHeapObj<mtClass> {
1389   friend class VMStructs;
1390  private:
1391   Klass*             _holder;
1392   JNIid*             _next;
1393   int                _offset;
1394 #ifdef ASSERT
1395   bool               _is_static_field_id;
1396 #endif
1397 
1398  public:
1399   // Accessors
1400   Klass* holder() const           { return _holder; }
1401   int offset() const              { return _offset; }
1402   JNIid* next()                   { return _next; }
1403   // Constructor
1404   JNIid(Klass* holder, int offset, JNIid* next);
1405   // Identifier lookup
1406   JNIid* find(int offset);
1407 
1408   bool find_local_field(fieldDescriptor* fd) {
1409     return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1410   }
1411 
1412   static void deallocate(JNIid* id);
1413   // Debugging
1414 #ifdef ASSERT
1415   bool is_static_field_id() const { return _is_static_field_id; }
1416   void set_is_static_field_id()   { _is_static_field_id = true; }
1417 #endif
1418   void verify(Klass* holder);
1419 };
1420 
1421 // An iterator that's used to access the inner classes indices in the
1422 // InstanceKlass::_inner_classes array.
1423 class InnerClassesIterator : public StackObj {
1424  private:
1425   Array<jushort>* _inner_classes;
1426   int _length;
1427   int _idx;
1428  public:
1429 
1430   InnerClassesIterator(const InstanceKlass* k) {
1431     _inner_classes = k->inner_classes();
1432     if (k->inner_classes() != NULL) {
1433       _length = _inner_classes->length();
1434       // The inner class array's length should be the multiple of
1435       // inner_class_next_offset if it only contains the InnerClasses
1436       // attribute data, or it should be
1437       // n*inner_class_next_offset+enclosing_method_attribute_size
1438       // if it also contains the EnclosingMethod data.
1439       assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1440               _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1441              "just checking");
1442       // Remove the enclosing_method portion if exists.
1443       if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1444         _length -= InstanceKlass::enclosing_method_attribute_size;
1445       }
1446     } else {
1447       _length = 0;
1448     }
1449     _idx = 0;
1450   }
1451 
1452   int length() const {
1453     return _length;
1454   }
1455 
1456   void next() {
1457     _idx += InstanceKlass::inner_class_next_offset;
1458   }
1459 
1460   bool done() const {
1461     return (_idx >= _length);
1462   }
1463 
1464   u2 inner_class_info_index() const {
1465     return _inner_classes->at(
1466                _idx + InstanceKlass::inner_class_inner_class_info_offset);
1467   }
1468 
1469   void set_inner_class_info_index(u2 index) {
1470     _inner_classes->at_put(
1471                _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1472   }
1473 
1474   u2 outer_class_info_index() const {
1475     return _inner_classes->at(
1476                _idx + InstanceKlass::inner_class_outer_class_info_offset);
1477   }
1478 
1479   void set_outer_class_info_index(u2 index) {
1480     _inner_classes->at_put(
1481                _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1482   }
1483 
1484   u2 inner_name_index() const {
1485     return _inner_classes->at(
1486                _idx + InstanceKlass::inner_class_inner_name_offset);
1487   }
1488 
1489   void set_inner_name_index(u2 index) {
1490     _inner_classes->at_put(
1491                _idx + InstanceKlass::inner_class_inner_name_offset, index);
1492   }
1493 
1494   u2 inner_access_flags() const {
1495     return _inner_classes->at(
1496                _idx + InstanceKlass::inner_class_access_flags_offset);
1497   }
1498 };
1499 
1500 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP