1 /*
   2  * Copyright (c) 1997, 2014, 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/classLoaderData.hpp"
  29 #include "memory/referenceType.hpp"
  30 #include "oops/annotations.hpp"
  31 #include "oops/constMethod.hpp"
  32 #include "oops/fieldInfo.hpp"
  33 #include "oops/instanceOop.hpp"
  34 #include "oops/klassVtable.hpp"
  35 #include "runtime/atomic.hpp"
  36 #include "runtime/handles.hpp"
  37 #include "runtime/os.hpp"
  38 #include "utilities/accessFlags.hpp"
  39 #include "utilities/bitMap.inline.hpp"
  40 #include "utilities/macros.hpp"
  41 #include "trace/traceMacros.hpp"
  42 
  43 // An InstanceKlass is the VM level representation of a Java class.
  44 // It contains all information needed for at class at execution runtime.
  45 
  46 //  InstanceKlass layout:
  47 //    [C++ vtbl pointer           ] Klass
  48 //    [subtype cache              ] Klass
  49 //    [instance size              ] Klass
  50 //    [java mirror                ] Klass
  51 //    [super                      ] Klass
  52 //    [access_flags               ] Klass
  53 //    [name                       ] Klass
  54 //    [first subklass             ] Klass
  55 //    [next sibling               ] Klass
  56 //    [array klasses              ]
  57 //    [methods                    ]
  58 //    [local interfaces           ]
  59 //    [transitive interfaces      ]
  60 //    [fields                     ]
  61 //    [constants                  ]
  62 //    [class loader               ]
  63 //    [source file name           ]
  64 //    [inner classes              ]
  65 //    [static field size          ]
  66 //    [nonstatic field size       ]
  67 //    [static oop fields size     ]
  68 //    [nonstatic oop maps size    ]
  69 //    [has finalize method        ]
  70 //    [deoptimization mark bit    ]
  71 //    [initialization state       ]
  72 //    [initializing thread        ]
  73 //    [Java vtable length         ]
  74 //    [oop map cache (stack maps) ]
  75 //    [EMBEDDED Java vtable             ] size in words = vtable_len
  76 //    [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
  77 //      The embedded nonstatic oop-map blocks are short pairs (offset, length)
  78 //      indicating where oops are located in instances of this klass.
  79 //    [EMBEDDED implementor of the interface] only exist for interface
  80 //    [EMBEDDED host klass        ] only exist for an anonymous class (JSR 292 enabled)
  81 
  82 
  83 // forward declaration for class -- see below for definition
  84 class SuperTypeClosure;
  85 class JNIid;
  86 class jniIdMapBase;
  87 class BreakpointInfo;
  88 class fieldDescriptor;
  89 class DepChange;
  90 class nmethodBucket;
  91 class PreviousVersionNode;
  92 class JvmtiCachedClassFieldMap;
  93 class MemberNameTable;
  94 
  95 // This is used in iterators below.
  96 class FieldClosure: public StackObj {
  97 public:
  98   virtual void do_field(fieldDescriptor* fd) = 0;
  99 };
 100 
 101 #ifndef PRODUCT
 102 // Print fields.
 103 // If "obj" argument to constructor is NULL, prints static fields, otherwise prints non-static fields.
 104 class FieldPrinter: public FieldClosure {
 105    oop _obj;
 106    outputStream* _st;
 107  public:
 108    FieldPrinter(outputStream* st, oop obj = NULL) : _obj(obj), _st(st) {}
 109    void do_field(fieldDescriptor* fd);
 110 };
 111 #endif  // !PRODUCT
 112 
 113 // ValueObjs embedded in klass. Describes where oops are located in instances of
 114 // this klass.
 115 class OopMapBlock VALUE_OBJ_CLASS_SPEC {
 116  public:
 117   // Byte offset of the first oop mapped by this block.
 118   int offset() const          { return _offset; }
 119   void set_offset(int offset) { _offset = offset; }
 120 
 121   // Number of oops in this block.
 122   uint count() const         { return _count; }
 123   void set_count(uint count) { _count = count; }
 124 
 125   // sizeof(OopMapBlock) in HeapWords.
 126   static const int size_in_words() {
 127     return align_size_up(int(sizeof(OopMapBlock)), HeapWordSize) >>
 128       LogHeapWordSize;
 129   }
 130 
 131  private:
 132   int  _offset;
 133   uint _count;
 134 };
 135 
 136 struct JvmtiCachedClassFileData;
 137 
 138 class InstanceKlass: public Klass {
 139   friend class VMStructs;
 140   friend class ClassFileParser;
 141   friend class CompileReplay;
 142 
 143  protected:
 144   // Constructor
 145   InstanceKlass(int vtable_len,
 146                 int itable_len,
 147                 int static_field_size,
 148                 int nonstatic_oop_map_size,
 149                 ReferenceType rt,
 150                 AccessFlags access_flags,
 151                 bool is_anonymous);
 152  public:
 153   static InstanceKlass* allocate_instance_klass(
 154                                           ClassLoaderData* loader_data,
 155                                           int vtable_len,
 156                                           int itable_len,
 157                                           int static_field_size,
 158                                           int nonstatic_oop_map_size,
 159                                           ReferenceType rt,
 160                                           AccessFlags access_flags,
 161                                           Symbol* name,
 162                                           Klass* super_klass,
 163                                           bool is_anonymous,
 164                                           TRAPS);
 165 
 166   InstanceKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
 167 
 168   // See "The Java Virtual Machine Specification" section 2.16.2-5 for a detailed description
 169   // of the class loading & initialization procedure, and the use of the states.
 170   enum ClassState {
 171     allocated,                          // allocated (but not yet linked)
 172     loaded,                             // loaded and inserted in class hierarchy (but not linked yet)
 173     linked,                             // successfully linked/verified (but not initialized yet)
 174     being_initialized,                  // currently running class initializer
 175     fully_initialized,                  // initialized (successfull final state)
 176     initialization_error                // error happened during initialization
 177   };
 178 
 179   static int number_of_instance_classes() { return _total_instanceKlass_count; }
 180 
 181  private:
 182   static volatile int _total_instanceKlass_count;
 183 
 184  protected:
 185   // Annotations for this class
 186   Annotations*    _annotations;
 187   // Array classes holding elements of this class.
 188   Klass*          _array_klasses;
 189   // Constant pool for this class.
 190   ConstantPool* _constants;
 191   // The InnerClasses attribute and EnclosingMethod attribute. The
 192   // _inner_classes is an array of shorts. If the class has InnerClasses
 193   // attribute, then the _inner_classes array begins with 4-tuples of shorts
 194   // [inner_class_info_index, outer_class_info_index,
 195   // inner_name_index, inner_class_access_flags] for the InnerClasses
 196   // attribute. If the EnclosingMethod attribute exists, it occupies the
 197   // last two shorts [class_index, method_index] of the array. If only
 198   // the InnerClasses attribute exists, the _inner_classes array length is
 199   // number_of_inner_classes * 4. If the class has both InnerClasses
 200   // and EnclosingMethod attributes the _inner_classes array length is
 201   // number_of_inner_classes * 4 + enclosing_method_attribute_size.
 202   Array<jushort>* _inner_classes;
 203 
 204   // the source debug extension for this klass, NULL if not specified.
 205   // Specified as UTF-8 string without terminating zero byte in the classfile,
 206   // it is stored in the instanceklass as a NULL-terminated UTF-8 string
 207   char*           _source_debug_extension;
 208   // Array name derived from this class which needs unreferencing
 209   // if this class is unloaded.
 210   Symbol*         _array_name;
 211 
 212   // Number of heapOopSize words used by non-static fields in this klass
 213   // (including inherited fields but after header_size()).
 214   int             _nonstatic_field_size;
 215   int             _static_field_size;    // number words used by static fields (oop and non-oop) in this klass
 216   // Constant pool index to the utf8 entry of the Generic signature,
 217   // or 0 if none.
 218   u2              _generic_signature_index;
 219   // Constant pool index to the utf8 entry for the name of source file
 220   // containing this klass, 0 if not specified.
 221   u2              _source_file_name_index;
 222   u2              _static_oop_field_count;// number of static oop fields in this klass
 223   u2              _java_fields_count;    // The number of declared Java fields
 224   int             _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks
 225 
 226   // _is_marked_dependent can be set concurrently, thus cannot be part of the
 227   // _misc_flags.
 228   bool            _is_marked_dependent;  // used for marking during flushing and deoptimization
 229   bool            _has_unloaded_dependent;
 230 
 231   enum {
 232     _misc_rewritten                = 1 << 0, // methods rewritten.
 233     _misc_has_nonstatic_fields     = 1 << 1, // for sizing with UseCompressedOops
 234     _misc_should_verify_class      = 1 << 2, // allow caching of preverification
 235     _misc_is_anonymous             = 1 << 3, // has embedded _host_klass field
 236     _misc_is_contended             = 1 << 4, // marked with contended annotation
 237     _misc_has_default_methods      = 1 << 5, // class/superclass/implemented interfaces has default methods
 238     _misc_declares_default_methods = 1 << 6  // directly declares default methods (any access)
 239   };
 240   u2              _misc_flags;
 241   u2              _minor_version;        // minor version number of class file
 242   u2              _major_version;        // major version number of class file
 243   Thread*         _init_thread;          // Pointer to current thread doing initialization (to handle recusive initialization)
 244   int             _vtable_len;           // length of Java vtable (in words)
 245   int             _itable_len;           // length of Java itable (in words)
 246   OopMapCache*    volatile _oop_map_cache;   // OopMapCache for all methods in the klass (allocated lazily)
 247   MemberNameTable* _member_names;        // Member names
 248   JNIid*          _jni_ids;              // First JNI identifier for static fields in this class
 249   jmethodID*      _methods_jmethod_ids;  // jmethodIDs corresponding to method_idnum, or NULL if none
 250   nmethodBucket*  _dependencies;         // list of dependent nmethods
 251   nmethod*        _osr_nmethods_head;    // Head of list of on-stack replacement nmethods for this class
 252   BreakpointInfo* _breakpoints;          // bpt lists, managed by Method*
 253   // Array of interesting part(s) of the previous version(s) of this
 254   // InstanceKlass. See PreviousVersionWalker below.
 255   GrowableArray<PreviousVersionNode *>* _previous_versions;
 256   // JVMTI fields can be moved to their own structure - see 6315920
 257   // JVMTI: cached class file, before retransformable agent modified it in CFLH
 258   JvmtiCachedClassFileData* _cached_class_file;
 259 
 260   volatile u2     _idnum_allocated_count;         // JNI/JVMTI: increments with the addition of methods, old ids don't change
 261 
 262   // Class states are defined as ClassState (see above).
 263   // Place the _init_state here to utilize the unused 2-byte after
 264   // _idnum_allocated_count.
 265   u1              _init_state;                    // state of class
 266   u1              _reference_type;                // reference type
 267 
 268   JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map;  // JVMTI: used during heap iteration
 269 
 270   NOT_PRODUCT(int _verify_count;)  // to avoid redundant verifies
 271 
 272   // Method array.
 273   Array<Method*>* _methods;
 274   // Default Method Array, concrete methods inherited from interfaces
 275   Array<Method*>* _default_methods;
 276   // Interface (Klass*s) this class declares locally to implement.
 277   Array<Klass*>* _local_interfaces;
 278   // Interface (Klass*s) this class implements transitively.
 279   Array<Klass*>* _transitive_interfaces;
 280   // Int array containing the original order of method in the class file (for JVMTI).
 281   Array<int>*     _method_ordering;
 282   // Int array containing the vtable_indices for default_methods
 283   // offset matches _default_methods offset
 284   Array<int>*     _default_vtable_indices;
 285 
 286   // Instance and static variable information, starts with 6-tuples of shorts
 287   // [access, name index, sig index, initval index, low_offset, high_offset]
 288   // for all fields, followed by the generic signature data at the end of
 289   // the array. Only fields with generic signature attributes have the generic
 290   // signature data set in the array. The fields array looks like following:
 291   //
 292   // f1: [access, name index, sig index, initial value index, low_offset, high_offset]
 293   // f2: [access, name index, sig index, initial value index, low_offset, high_offset]
 294   //      ...
 295   // fn: [access, name index, sig index, initial value index, low_offset, high_offset]
 296   //     [generic signature index]
 297   //     [generic signature index]
 298   //     ...
 299   Array<u2>*      _fields;
 300 
 301   // embedded Java vtable follows here
 302   // embedded Java itables follows here
 303   // embedded static fields follows here
 304   // embedded nonstatic oop-map blocks follows here
 305   // embedded implementor of this interface follows here
 306   //   The embedded implementor only exists if the current klass is an
 307   //   iterface. The possible values of the implementor fall into following
 308   //   three cases:
 309   //     NULL: no implementor.
 310   //     A Klass* that's not itself: one implementor.
 311   //     Itself: more than one implementors.
 312   // embedded host klass follows here
 313   //   The embedded host klass only exists in an anonymous class for
 314   //   dynamic language support (JSR 292 enabled). The host class grants
 315   //   its access privileges to this class also. The host class is either
 316   //   named, or a previously loaded anonymous class. A non-anonymous class
 317   //   or an anonymous class loaded through normal classloading does not
 318   //   have this embedded field.
 319   //
 320 
 321   friend class SystemDictionary;
 322 
 323  public:
 324   bool has_nonstatic_fields() const        {
 325     return (_misc_flags & _misc_has_nonstatic_fields) != 0;
 326   }
 327   void set_has_nonstatic_fields(bool b)    {
 328     if (b) {
 329       _misc_flags |= _misc_has_nonstatic_fields;
 330     } else {
 331       _misc_flags &= ~_misc_has_nonstatic_fields;
 332     }
 333   }
 334 
 335   // field sizes
 336   int nonstatic_field_size() const         { return _nonstatic_field_size; }
 337   void set_nonstatic_field_size(int size)  { _nonstatic_field_size = size; }
 338 
 339   int static_field_size() const            { return _static_field_size; }
 340   void set_static_field_size(int size)     { _static_field_size = size; }
 341 
 342   int static_oop_field_count() const       { return (int)_static_oop_field_count; }
 343   void set_static_oop_field_count(u2 size) { _static_oop_field_count = size; }
 344 
 345   // Java vtable
 346   int  vtable_length() const               { return _vtable_len; }
 347   void set_vtable_length(int len)          { _vtable_len = len; }
 348 
 349   // Java itable
 350   int  itable_length() const               { return _itable_len; }
 351   void set_itable_length(int len)          { _itable_len = len; }
 352 
 353   // array klasses
 354   Klass* array_klasses() const             { return _array_klasses; }
 355   void set_array_klasses(Klass* k)         { _array_klasses = k; }
 356 
 357   // methods
 358   Array<Method*>* methods() const          { return _methods; }
 359   void set_methods(Array<Method*>* a)      { _methods = a; }
 360   Method* method_with_idnum(int idnum);
 361 
 362   // method ordering
 363   Array<int>* method_ordering() const     { return _method_ordering; }
 364   void set_method_ordering(Array<int>* m) { _method_ordering = m; }
 365   void copy_method_ordering(intArray* m, TRAPS);
 366 
 367   // default_methods
 368   Array<Method*>* default_methods() const  { return _default_methods; }
 369   void set_default_methods(Array<Method*>* a) { _default_methods = a; }
 370 
 371   // default method vtable_indices
 372   Array<int>* default_vtable_indices() const { return _default_vtable_indices; }
 373   void set_default_vtable_indices(Array<int>* v) { _default_vtable_indices = v; }
 374   Array<int>* create_new_default_vtable_indices(int len, TRAPS);
 375 
 376   // interfaces
 377   Array<Klass*>* local_interfaces() const          { return _local_interfaces; }
 378   void set_local_interfaces(Array<Klass*>* a)      {
 379     guarantee(_local_interfaces == NULL || a == NULL, "Just checking");
 380     _local_interfaces = a; }
 381 
 382   Array<Klass*>* transitive_interfaces() const     { return _transitive_interfaces; }
 383   void set_transitive_interfaces(Array<Klass*>* a) {
 384     guarantee(_transitive_interfaces == NULL || a == NULL, "Just checking");
 385     _transitive_interfaces = a;
 386   }
 387 
 388  private:
 389   friend class fieldDescriptor;
 390   FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }
 391 
 392  public:
 393   int     field_offset      (int index) const { return field(index)->offset(); }
 394   int     field_access_flags(int index) const { return field(index)->access_flags(); }
 395   Symbol* field_name        (int index) const { return field(index)->name(constants()); }
 396   Symbol* field_signature   (int index) const { return field(index)->signature(constants()); }
 397 
 398   // Number of Java declared fields
 399   int java_fields_count() const           { return (int)_java_fields_count; }
 400 
 401   Array<u2>* fields() const            { return _fields; }
 402   void set_fields(Array<u2>* f, u2 java_fields_count) {
 403     guarantee(_fields == NULL || f == NULL, "Just checking");
 404     _fields = f;
 405     _java_fields_count = java_fields_count;
 406   }
 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   enum InnerClassAttributeOffset {
 413     // From http://mirror.eng/products/jdk/1.1/docs/guide/innerclasses/spec/innerclasses.doc10.html#18814
 414     inner_class_inner_class_info_offset = 0,
 415     inner_class_outer_class_info_offset = 1,
 416     inner_class_inner_name_offset = 2,
 417     inner_class_access_flags_offset = 3,
 418     inner_class_next_offset = 4
 419   };
 420 
 421   enum EnclosingMethodAttributeOffset {
 422     enclosing_method_class_index_offset = 0,
 423     enclosing_method_method_index_offset = 1,
 424     enclosing_method_attribute_size = 2
 425   };
 426 
 427   // method override check
 428   bool is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS);
 429 
 430   // package
 431   bool is_same_class_package(Klass* class2);
 432   bool is_same_class_package(oop classloader2, Symbol* classname2);
 433   static bool is_same_class_package(oop class_loader1, Symbol* class_name1, oop class_loader2, Symbol* class_name2);
 434 
 435   // find an enclosing class (defined where original code was, in jvm.cpp!)
 436   Klass* compute_enclosing_class(bool* inner_is_member, TRAPS) {
 437     instanceKlassHandle self(THREAD, this);
 438     return compute_enclosing_class_impl(self, inner_is_member, THREAD);
 439   }
 440   static Klass* compute_enclosing_class_impl(instanceKlassHandle self,
 441                                                bool* inner_is_member, TRAPS);
 442 
 443   // tell if two classes have the same enclosing class (at package level)
 444   bool is_same_package_member(Klass* class2, TRAPS) {
 445     instanceKlassHandle self(THREAD, this);
 446     return is_same_package_member_impl(self, class2, THREAD);
 447   }
 448   static bool is_same_package_member_impl(instanceKlassHandle self,
 449                                           Klass* class2, TRAPS);
 450 
 451   // initialization state
 452   bool is_loaded() const                   { return _init_state >= loaded; }
 453   bool is_linked() const                   { return _init_state >= linked; }
 454   bool is_initialized() const              { return _init_state == fully_initialized; }
 455   bool is_not_initialized() const          { return _init_state <  being_initialized; }
 456   bool is_being_initialized() const        { return _init_state == being_initialized; }
 457   bool is_in_error_state() const           { return _init_state == initialization_error; }
 458   bool is_reentrant_initialization(Thread *thread)  { return thread == _init_thread; }
 459   ClassState  init_state()                 { return (ClassState)_init_state; }
 460   bool is_rewritten() const                { return (_misc_flags & _misc_rewritten) != 0; }
 461 
 462   // defineClass specified verification
 463   bool should_verify_class() const         {
 464     return (_misc_flags & _misc_should_verify_class) != 0;
 465   }
 466   void set_should_verify_class(bool value) {
 467     if (value) {
 468       _misc_flags |= _misc_should_verify_class;
 469     } else {
 470       _misc_flags &= ~_misc_should_verify_class;
 471     }
 472   }
 473 
 474   // marking
 475   bool is_marked_dependent() const         { return _is_marked_dependent; }
 476   void set_is_marked_dependent(bool value) { _is_marked_dependent = value; }
 477 
 478   bool has_unloaded_dependent() const         { return _has_unloaded_dependent; }
 479   void set_has_unloaded_dependent(bool value) { _has_unloaded_dependent = value; }
 480 
 481   // initialization (virtuals from Klass)
 482   bool should_be_initialized() const;  // means that initialize should be called
 483   void initialize(TRAPS);
 484   void link_class(TRAPS);
 485   bool link_class_or_fail(TRAPS); // returns false on failure
 486   void unlink_class();
 487   void rewrite_class(TRAPS);
 488   void link_methods(TRAPS);
 489   Method* class_initializer();
 490 
 491   // set the class to initialized if no static initializer is present
 492   void eager_initialize(Thread *thread);
 493 
 494   // reference type
 495   ReferenceType reference_type() const     { return (ReferenceType)_reference_type; }
 496   void set_reference_type(ReferenceType t) {
 497     assert(t == (u1)t, "overflow");
 498     _reference_type = (u1)t;
 499   }
 500 
 501   static ByteSize reference_type_offset() { return in_ByteSize(offset_of(InstanceKlass, _reference_type)); }
 502 
 503   // find local field, returns true if found
 504   bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 505   // find field in direct superinterfaces, returns the interface in which the field is defined
 506   Klass* find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 507   // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 508   Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 509   // find instance or static fields according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 510   Klass* find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const;
 511 
 512   // find a non-static or static field given its offset within the class.
 513   bool contains_field_offset(int offset) {
 514     return instanceOopDesc::contains_field_offset(offset, nonstatic_field_size());
 515   }
 516 
 517   bool find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 518   bool find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const;
 519 
 520   // find a local method (returns NULL if not found)
 521   Method* find_method(Symbol* name, Symbol* signature) const;
 522   static Method* find_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
 523   static Method* find_instance_method(Array<Method*>* methods, Symbol* name, Symbol* signature);
 524 
 525   // find a local method index in default_methods (returns -1 if not found)
 526   static int find_method_index(Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass);
 527 
 528   // lookup operation (returns NULL if not found)
 529   Method* uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const;
 530 
 531   // lookup a method in all the interfaces that this class implements
 532   // (returns NULL if not found)
 533   Method* lookup_method_in_all_interfaces(Symbol* name, Symbol* signature, MethodLookupMode mode) const;
 534 
 535   // lookup a method in local defaults then in all interfaces
 536   // (returns NULL if not found)
 537   Method* lookup_method_in_ordered_interfaces(Symbol* name, Symbol* signature) const;
 538 
 539   // Find method indices by name.  If a method with the specified name is
 540   // found the index to the first method is returned, and 'end' is filled in
 541   // with the index of first non-name-matching method.  If no method is found
 542   // -1 is returned.
 543   int find_method_by_name(Symbol* name, int* end);
 544   static int find_method_by_name(Array<Method*>* methods, Symbol* name, int* end);
 545 
 546   // constant pool
 547   ConstantPool* constants() const        { return _constants; }
 548   void set_constants(ConstantPool* c)    { _constants = c; }
 549 
 550   // protection domain
 551   oop protection_domain() const;
 552 
 553   // signers
 554   objArrayOop signers() const;
 555 
 556   // host class
 557   Klass* host_klass() const              {
 558     Klass** hk = (Klass**)adr_host_klass();
 559     if (hk == NULL) {
 560       return NULL;
 561     } else {
 562       assert(*hk != NULL, "host klass should always be set if the address is not null");
 563       return *hk;
 564     }
 565   }
 566   void set_host_klass(Klass* host)            {
 567     assert(is_anonymous(), "not anonymous");
 568     Klass** addr = (Klass**)adr_host_klass();
 569     assert(addr != NULL, "no reversed space");
 570     if (addr != NULL) {
 571       *addr = host;
 572     }
 573   }
 574   bool is_anonymous() const                {
 575     return (_misc_flags & _misc_is_anonymous) != 0;
 576   }
 577   void set_is_anonymous(bool value)        {
 578     if (value) {
 579       _misc_flags |= _misc_is_anonymous;
 580     } else {
 581       _misc_flags &= ~_misc_is_anonymous;
 582     }
 583   }
 584 
 585   // Oop that keeps the metadata for this class from being unloaded
 586   // in places where the metadata is stored in other places, like nmethods
 587   oop klass_holder() const {
 588     return is_anonymous() ? java_mirror() : class_loader();
 589   }
 590 
 591   bool is_contended() const                {
 592     return (_misc_flags & _misc_is_contended) != 0;
 593   }
 594   void set_is_contended(bool value)        {
 595     if (value) {
 596       _misc_flags |= _misc_is_contended;
 597     } else {
 598       _misc_flags &= ~_misc_is_contended;
 599     }
 600   }
 601 
 602   // source file name
 603   Symbol* source_file_name() const               {
 604     return (_source_file_name_index == 0) ?
 605       (Symbol*)NULL : _constants->symbol_at(_source_file_name_index);
 606   }
 607   u2 source_file_name_index() const              {
 608     return _source_file_name_index;
 609   }
 610   void set_source_file_name_index(u2 sourcefile_index) {
 611     _source_file_name_index = sourcefile_index;
 612   }
 613 
 614   // minor and major version numbers of class file
 615   u2 minor_version() const                 { return _minor_version; }
 616   void set_minor_version(u2 minor_version) { _minor_version = minor_version; }
 617   u2 major_version() const                 { return _major_version; }
 618   void set_major_version(u2 major_version) { _major_version = major_version; }
 619 
 620   // source debug extension
 621   char* source_debug_extension() const     { return _source_debug_extension; }
 622   void set_source_debug_extension(char* array, int length);
 623 
 624   // symbol unloading support (refcount already added)
 625   Symbol* array_name()                     { return _array_name; }
 626   void set_array_name(Symbol* name)        { assert(_array_name == NULL  || name == NULL, "name already created"); _array_name = name; }
 627 
 628   // nonstatic oop-map blocks
 629   static int nonstatic_oop_map_size(unsigned int oop_map_count) {
 630     return oop_map_count * OopMapBlock::size_in_words();
 631   }
 632   unsigned int nonstatic_oop_map_count() const {
 633     return _nonstatic_oop_map_size / OopMapBlock::size_in_words();
 634   }
 635   int nonstatic_oop_map_size() const { return _nonstatic_oop_map_size; }
 636   void set_nonstatic_oop_map_size(int words) {
 637     _nonstatic_oop_map_size = words;
 638   }
 639 
 640   // RedefineClasses() support for previous versions:
 641   void add_previous_version(instanceKlassHandle ikh, BitMap *emcp_methods,
 642          int emcp_method_count);
 643   // If the _previous_versions array is non-NULL, then this klass
 644   // has been redefined at least once even if we aren't currently
 645   // tracking a previous version.
 646   bool has_been_redefined() const { return _previous_versions != NULL; }
 647   bool has_previous_version() const;
 648   void init_previous_versions() {
 649     _previous_versions = NULL;
 650   }
 651   GrowableArray<PreviousVersionNode *>* previous_versions() const {
 652     return _previous_versions;
 653   }
 654 
 655   static void purge_previous_versions(InstanceKlass* ik);
 656 
 657   // JVMTI: Support for caching a class file before it is modified by an agent that can do retransformation
 658   void set_cached_class_file(JvmtiCachedClassFileData *data) {
 659     _cached_class_file = data;
 660   }
 661   JvmtiCachedClassFileData * get_cached_class_file() { return _cached_class_file; }
 662   jint get_cached_class_file_len();
 663   unsigned char * get_cached_class_file_bytes();
 664 
 665   // JVMTI: Support for caching of field indices, types, and offsets
 666   void set_jvmti_cached_class_field_map(JvmtiCachedClassFieldMap* descriptor) {
 667     _jvmti_cached_class_field_map = descriptor;
 668   }
 669   JvmtiCachedClassFieldMap* jvmti_cached_class_field_map() const {
 670     return _jvmti_cached_class_field_map;
 671   }
 672 
 673   bool has_default_methods() const {
 674     return (_misc_flags & _misc_has_default_methods) != 0;
 675   }
 676   void set_has_default_methods(bool b) {
 677     if (b) {
 678       _misc_flags |= _misc_has_default_methods;
 679     } else {
 680       _misc_flags &= ~_misc_has_default_methods;
 681     }
 682   }
 683 
 684   bool declares_default_methods() const {
 685     return (_misc_flags & _misc_declares_default_methods) != 0;
 686   }
 687   void set_declares_default_methods(bool b) {
 688     if (b) {
 689       _misc_flags |= _misc_declares_default_methods;
 690     } else {
 691       _misc_flags &= ~_misc_declares_default_methods;
 692     }
 693   }
 694 
 695   // for adding methods, ConstMethod::UNSET_IDNUM means no more ids available
 696   inline u2 next_method_idnum();
 697   void set_initial_method_idnum(u2 value)             { _idnum_allocated_count = value; }
 698 
 699   // generics support
 700   Symbol* generic_signature() const                   {
 701     return (_generic_signature_index == 0) ?
 702       (Symbol*)NULL : _constants->symbol_at(_generic_signature_index);
 703   }
 704   u2 generic_signature_index() const                  {
 705     return _generic_signature_index;
 706   }
 707   void set_generic_signature_index(u2 sig_index)      {
 708     _generic_signature_index = sig_index;
 709   }
 710 
 711   u2 enclosing_method_data(int offset);
 712   u2 enclosing_method_class_index() {
 713     return enclosing_method_data(enclosing_method_class_index_offset);
 714   }
 715   u2 enclosing_method_method_index() {
 716     return enclosing_method_data(enclosing_method_method_index_offset);
 717   }
 718   void set_enclosing_method_indices(u2 class_index,
 719                                     u2 method_index);
 720 
 721   // jmethodID support
 722   static jmethodID get_jmethod_id(instanceKlassHandle ik_h,
 723                      methodHandle method_h);
 724   static jmethodID get_jmethod_id_fetch_or_update(instanceKlassHandle ik_h,
 725                      size_t idnum, jmethodID new_id, jmethodID* new_jmeths,
 726                      jmethodID* to_dealloc_id_p,
 727                      jmethodID** to_dealloc_jmeths_p);
 728   static void get_jmethod_id_length_value(jmethodID* cache, size_t idnum,
 729                 size_t *length_p, jmethodID* id_p);
 730   jmethodID jmethod_id_or_null(Method* method);
 731 
 732   // annotations support
 733   Annotations* annotations() const          { return _annotations; }
 734   void set_annotations(Annotations* anno)   { _annotations = anno; }
 735 
 736   AnnotationArray* class_annotations() const {
 737     return (_annotations != NULL) ? _annotations->class_annotations() : NULL;
 738   }
 739   Array<AnnotationArray*>* fields_annotations() const {
 740     return (_annotations != NULL) ? _annotations->fields_annotations() : NULL;
 741   }
 742   AnnotationArray* class_type_annotations() const {
 743     return (_annotations != NULL) ? _annotations->class_type_annotations() : NULL;
 744   }
 745   Array<AnnotationArray*>* fields_type_annotations() const {
 746     return (_annotations != NULL) ? _annotations->fields_type_annotations() : NULL;
 747   }
 748   // allocation
 749   instanceOop allocate_instance(TRAPS);
 750 
 751   // additional member function to return a handle
 752   instanceHandle allocate_instance_handle(TRAPS)      { return instanceHandle(THREAD, allocate_instance(THREAD)); }
 753 
 754   objArrayOop allocate_objArray(int n, int length, TRAPS);
 755   // Helper function
 756   static instanceOop register_finalizer(instanceOop i, TRAPS);
 757 
 758   // Check whether reflection/jni/jvm code is allowed to instantiate this class;
 759   // if not, throw either an Error or an Exception.
 760   virtual void check_valid_for_instantiation(bool throwError, TRAPS);
 761 
 762   // initialization
 763   void call_class_initializer(TRAPS);
 764   void set_initialization_state_and_notify(ClassState state, TRAPS);
 765 
 766   // OopMapCache support
 767   OopMapCache* oop_map_cache()               { return _oop_map_cache; }
 768   void set_oop_map_cache(OopMapCache *cache) { _oop_map_cache = cache; }
 769   void mask_for(methodHandle method, int bci, InterpreterOopMap* entry);
 770 
 771   // JNI identifier support (for static fields - for jni performance)
 772   JNIid* jni_ids()                               { return _jni_ids; }
 773   void set_jni_ids(JNIid* ids)                   { _jni_ids = ids; }
 774   JNIid* jni_id_for(int offset);
 775 
 776   // maintenance of deoptimization dependencies
 777   int mark_dependent_nmethods(DepChange& changes);
 778   void add_dependent_nmethod(nmethod* nm);
 779   void remove_dependent_nmethod(nmethod* nm);
 780 
 781   // On-stack replacement support
 782   nmethod* osr_nmethods_head() const         { return _osr_nmethods_head; };
 783   void set_osr_nmethods_head(nmethod* h)     { _osr_nmethods_head = h; };
 784   void add_osr_nmethod(nmethod* n);
 785   void remove_osr_nmethod(nmethod* n);
 786   nmethod* lookup_osr_nmethod(const Method* m, int bci, int level, bool match_level) const;
 787 
 788   // Breakpoint support (see methods on Method* for details)
 789   BreakpointInfo* breakpoints() const       { return _breakpoints; };
 790   void set_breakpoints(BreakpointInfo* bps) { _breakpoints = bps; };
 791 
 792   // support for stub routines
 793   static ByteSize init_state_offset()  { return in_ByteSize(offset_of(InstanceKlass, _init_state)); }
 794   TRACE_DEFINE_OFFSET;
 795   static ByteSize init_thread_offset() { return in_ByteSize(offset_of(InstanceKlass, _init_thread)); }
 796 
 797   // subclass/subinterface checks
 798   bool implements_interface(Klass* k) const;
 799   bool is_same_or_direct_interface(Klass* k) const;
 800 
 801   // Access to the implementor of an interface.
 802   Klass* implementor() const
 803   {
 804     Klass** k = adr_implementor();
 805     if (k == NULL) {
 806       return NULL;
 807     } else {
 808       return *k;
 809     }
 810   }
 811 
 812   void set_implementor(Klass* k) {
 813     assert(is_interface(), "not interface");
 814     Klass** addr = adr_implementor();
 815     assert(addr != NULL, "null addr");
 816     if (addr != NULL) {
 817       *addr = k;
 818     }
 819   }
 820 
 821   int  nof_implementors() const       {
 822     Klass* k = implementor();
 823     if (k == NULL) {
 824       return 0;
 825     } else if (k != this) {
 826       return 1;
 827     } else {
 828       return 2;
 829     }
 830   }
 831 
 832   void add_implementor(Klass* k);  // k is a new class that implements this interface
 833   void init_implementor();           // initialize
 834 
 835   // link this class into the implementors list of every interface it implements
 836   void process_interfaces(Thread *thread);
 837 
 838   // virtual operations from Klass
 839   bool is_leaf_class() const               { return _subklass == NULL; }
 840   GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
 841   bool compute_is_subtype_of(Klass* k);
 842   bool can_be_primary_super_slow() const;
 843   int oop_size(oop obj)  const             { return size_helper(); }
 844   bool oop_is_instance_slow() const        { return true; }
 845 
 846   // Iterators
 847   void do_local_static_fields(FieldClosure* cl);
 848   void do_nonstatic_fields(FieldClosure* cl); // including inherited fields
 849   void do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle, TRAPS);
 850 
 851   void methods_do(void f(Method* method));
 852   void array_klasses_do(void f(Klass* k));
 853   void array_klasses_do(void f(Klass* k, TRAPS), TRAPS);
 854   bool super_types_do(SuperTypeClosure* blk);
 855 
 856   // Casting from Klass*
 857   static InstanceKlass* cast(Klass* k) {
 858     assert(k->is_klass(), "must be");
 859     assert(k->oop_is_instance(), "cast to InstanceKlass");
 860     return (InstanceKlass*) k;
 861   }
 862 
 863   InstanceKlass* java_super() const {
 864     return (super() == NULL) ? NULL : cast(super());
 865   }
 866 
 867   // Sizing (in words)
 868   static int header_size()            { return align_object_offset(sizeof(InstanceKlass)/HeapWordSize); }
 869 
 870   static int size(int vtable_length, int itable_length,
 871                   int nonstatic_oop_map_size,
 872                   bool is_interface, bool is_anonymous) {
 873     return align_object_size(header_size() +
 874            align_object_offset(vtable_length) +
 875            align_object_offset(itable_length) +
 876            ((is_interface || is_anonymous) ?
 877              align_object_offset(nonstatic_oop_map_size) :
 878              nonstatic_oop_map_size) +
 879            (is_interface ? (int)sizeof(Klass*)/HeapWordSize : 0) +
 880            (is_anonymous ? (int)sizeof(Klass*)/HeapWordSize : 0));
 881   }
 882   int size() const                    { return size(vtable_length(),
 883                                                itable_length(),
 884                                                nonstatic_oop_map_size(),
 885                                                is_interface(),
 886                                                is_anonymous());
 887   }
 888 #if INCLUDE_SERVICES
 889   virtual void collect_statistics(KlassSizeStats *sz) const;
 890 #endif
 891 
 892   static int vtable_start_offset()    { return header_size(); }
 893   static int vtable_length_offset()   { return offset_of(InstanceKlass, _vtable_len) / HeapWordSize; }
 894 
 895   intptr_t* start_of_vtable() const        { return ((intptr_t*)this) + vtable_start_offset(); }
 896   intptr_t* start_of_itable() const        { return start_of_vtable() + align_object_offset(vtable_length()); }
 897   int  itable_offset_in_words() const { return start_of_itable() - (intptr_t*)this; }
 898 
 899   intptr_t* end_of_itable() const          { return start_of_itable() + itable_length(); }
 900 
 901   address static_field_addr(int offset);
 902 
 903   OopMapBlock* start_of_nonstatic_oop_maps() const {
 904     return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length()));
 905   }
 906 
 907   Klass** end_of_nonstatic_oop_maps() const {
 908     return (Klass**)(start_of_nonstatic_oop_maps() +
 909                      nonstatic_oop_map_count());
 910   }
 911 
 912   Klass** adr_implementor() const {
 913     if (is_interface()) {
 914       return (Klass**)end_of_nonstatic_oop_maps();
 915     } else {
 916       return NULL;
 917     }
 918   };
 919 
 920   Klass** adr_host_klass() const {
 921     if (is_anonymous()) {
 922       Klass** adr_impl = adr_implementor();
 923       if (adr_impl != NULL) {
 924         return adr_impl + 1;
 925       } else {
 926         return end_of_nonstatic_oop_maps();
 927       }
 928     } else {
 929       return NULL;
 930     }
 931   }
 932 
 933   // Use this to return the size of an instance in heap words:
 934   int size_helper() const {
 935     return layout_helper_to_size_helper(layout_helper());
 936   }
 937 
 938   // This bit is initialized in classFileParser.cpp.
 939   // It is false under any of the following conditions:
 940   //  - the class is abstract (including any interface)
 941   //  - the class has a finalizer (if !RegisterFinalizersAtInit)
 942   //  - the class size is larger than FastAllocateSizeLimit
 943   //  - the class is java/lang/Class, which cannot be allocated directly
 944   bool can_be_fastpath_allocated() const {
 945     return !layout_helper_needs_slow_path(layout_helper());
 946   }
 947 
 948   // Java vtable/itable
 949   klassVtable* vtable() const;        // return new klassVtable wrapper
 950   inline Method* method_at_vtable(int index);
 951   klassItable* itable() const;        // return new klassItable wrapper
 952   Method* method_at_itable(Klass* holder, int index, TRAPS);
 953 
 954 #if INCLUDE_JVMTI
 955   void adjust_default_methods(Method** old_methods, Method** new_methods,
 956                               int methods_length, bool* trace_name_printed);
 957 #endif // INCLUDE_JVMTI
 958 
 959   // Garbage collection
 960   void oop_follow_contents(oop obj);
 961   int  oop_adjust_pointers(oop obj);
 962 
 963   void clean_implementors_list(BoolObjectClosure* is_alive);
 964   void clean_method_data(BoolObjectClosure* is_alive);
 965   void clean_dependent_nmethods();
 966 
 967   // Explicit metaspace deallocation of fields
 968   // For RedefineClasses and class file parsing errors, we need to deallocate
 969   // instanceKlasses and the metadata they point to.
 970   void deallocate_contents(ClassLoaderData* loader_data);
 971   static void deallocate_methods(ClassLoaderData* loader_data,
 972                                  Array<Method*>* methods);
 973   void static deallocate_interfaces(ClassLoaderData* loader_data,
 974                                     Klass* super_klass,
 975                                     Array<Klass*>* local_interfaces,
 976                                     Array<Klass*>* transitive_interfaces);
 977 
 978   // The constant pool is on stack if any of the methods are executing or
 979   // referenced by handles.
 980   bool on_stack() const { return _constants->on_stack(); }
 981 
 982   // callbacks for actions during class unloading
 983   static void notify_unload_class(InstanceKlass* ik);
 984   static void release_C_heap_structures(InstanceKlass* ik);
 985 
 986   // Parallel Scavenge and Parallel Old
 987   PARALLEL_GC_DECLS
 988 
 989   // Naming
 990   const char* signature_name() const;
 991 
 992   // Iterators
 993   int oop_oop_iterate(oop obj, ExtendedOopClosure* blk) {
 994     return oop_oop_iterate_v(obj, blk);
 995   }
 996 
 997   int oop_oop_iterate_m(oop obj, ExtendedOopClosure* blk, MemRegion mr) {
 998     return oop_oop_iterate_v_m(obj, blk, mr);
 999   }
1000 
1001 #define InstanceKlass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix)      \
1002   int  oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk);           \
1003   int  oop_oop_iterate##nv_suffix##_m(oop obj, OopClosureType* blk,        \
1004                                       MemRegion mr);
1005 
1006   ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DECL)
1007   ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DECL)
1008 
1009 #if INCLUDE_ALL_GCS
1010 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
1011   int  oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* blk);
1012 
1013   ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
1014   ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DECL)
1015 #endif // INCLUDE_ALL_GCS
1016 
1017   u2 idnum_allocated_count() const      { return _idnum_allocated_count; }
1018 
1019 public:
1020   void set_in_error_state() {
1021     assert(DumpSharedSpaces, "only call this when dumping archive");
1022     _init_state = initialization_error;
1023   }
1024   bool check_sharing_error_state();
1025 
1026 private:
1027   // initialization state
1028 #ifdef ASSERT
1029   void set_init_state(ClassState state);
1030 #else
1031   void set_init_state(ClassState state) { _init_state = (u1)state; }
1032 #endif
1033   void set_rewritten()                  { _misc_flags |= _misc_rewritten; }
1034   void set_init_thread(Thread *thread)  { _init_thread = thread; }
1035 
1036   // The RedefineClasses() API can cause new method idnums to be needed
1037   // which will cause the caches to grow. Safety requires different
1038   // cache management logic if the caches can grow instead of just
1039   // going from NULL to non-NULL.
1040   bool idnum_can_increment() const      { return has_been_redefined(); }
1041   jmethodID* methods_jmethod_ids_acquire() const
1042          { return (jmethodID*)OrderAccess::load_ptr_acquire(&_methods_jmethod_ids); }
1043   void release_set_methods_jmethod_ids(jmethodID* jmeths)
1044          { OrderAccess::release_store_ptr(&_methods_jmethod_ids, jmeths); }
1045 
1046   // Lock during initialization
1047 public:
1048   // Lock for (1) initialization; (2) access to the ConstantPool of this class.
1049   // Must be one per class and it has to be a VM internal object so java code
1050   // cannot lock it (like the mirror).
1051   // It has to be an object not a Mutex because it's held through java calls.
1052   oop init_lock() const;
1053 private:
1054   void fence_and_clear_init_lock();
1055 
1056   // Static methods that are used to implement member methods where an exposed this pointer
1057   // is needed due to possible GCs
1058   static bool link_class_impl                           (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
1059   static bool verify_code                               (instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS);
1060   static void initialize_impl                           (instanceKlassHandle this_oop, TRAPS);
1061   static void initialize_super_interfaces               (instanceKlassHandle this_oop, TRAPS);
1062   static void eager_initialize_impl                     (instanceKlassHandle this_oop);
1063   static void set_initialization_state_and_notify_impl  (instanceKlassHandle this_oop, ClassState state, TRAPS);
1064   static void call_class_initializer_impl               (instanceKlassHandle this_oop, TRAPS);
1065   static Klass* array_klass_impl                      (instanceKlassHandle this_oop, bool or_null, int n, TRAPS);
1066   static void do_local_static_fields_impl               (instanceKlassHandle this_oop, void f(fieldDescriptor* fd, Handle, TRAPS), Handle, TRAPS);
1067   /* jni_id_for_impl for jfieldID only */
1068   static JNIid* jni_id_for_impl                         (instanceKlassHandle this_oop, int offset);
1069 
1070   // Returns the array class for the n'th dimension
1071   Klass* array_klass_impl(bool or_null, int n, TRAPS);
1072 
1073   // Returns the array class with this class as element type
1074   Klass* array_klass_impl(bool or_null, TRAPS);
1075 
1076   // find a local method (returns NULL if not found)
1077   Method* find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const;
1078   static Method* find_method_impl(Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass);
1079 
1080   // Free CHeap allocated fields.
1081   void release_C_heap_structures();
1082 public:
1083   // CDS support - remove and restore oops from metadata. Oops are not shared.
1084   virtual void remove_unshareable_info();
1085   virtual void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS);
1086 
1087   // jvm support
1088   jint compute_modifier_flags(TRAPS) const;
1089 
1090   // JSR-292 support
1091   MemberNameTable* member_names() { return _member_names; }
1092   void set_member_names(MemberNameTable* member_names) { _member_names = member_names; }
1093   void add_member_name(int index, Handle member_name);
1094   oop  get_member_name(int index);
1095 
1096 public:
1097   // JVMTI support
1098   jint jvmti_class_status() const;
1099 
1100  public:
1101   // Printing
1102 #ifndef PRODUCT
1103   void print_on(outputStream* st) const;
1104 #endif
1105   void print_value_on(outputStream* st) const;
1106 
1107   void oop_print_value_on(oop obj, outputStream* st);
1108 
1109 #ifndef PRODUCT
1110   void oop_print_on      (oop obj, outputStream* st);
1111 
1112   void print_dependent_nmethods(bool verbose = false);
1113   bool is_dependent_nmethod(nmethod* nm);
1114 #endif
1115 
1116   const char* internal_name() const;
1117 
1118   // Verification
1119   void verify_on(outputStream* st);
1120 
1121   void oop_verify_on(oop obj, outputStream* st);
1122 };
1123 
1124 inline Method* InstanceKlass::method_at_vtable(int index)  {
1125 #ifndef PRODUCT
1126   assert(index >= 0, "valid vtable index");
1127   if (DebugVtables) {
1128     verify_vtable_index(index);
1129   }
1130 #endif
1131   vtableEntry* ve = (vtableEntry*)start_of_vtable();
1132   return ve[index].method();
1133 }
1134 
1135 // for adding methods
1136 // UNSET_IDNUM return means no more ids available
1137 inline u2 InstanceKlass::next_method_idnum() {
1138   if (_idnum_allocated_count == ConstMethod::MAX_IDNUM) {
1139     return ConstMethod::UNSET_IDNUM; // no more ids available
1140   } else {
1141     return _idnum_allocated_count++;
1142   }
1143 }
1144 
1145 
1146 /* JNIid class for jfieldIDs only */
1147 class JNIid: public CHeapObj<mtClass> {
1148   friend class VMStructs;
1149  private:
1150   Klass*             _holder;
1151   JNIid*             _next;
1152   int                _offset;
1153 #ifdef ASSERT
1154   bool               _is_static_field_id;
1155 #endif
1156 
1157  public:
1158   // Accessors
1159   Klass* holder() const           { return _holder; }
1160   int offset() const              { return _offset; }
1161   JNIid* next()                   { return _next; }
1162   // Constructor
1163   JNIid(Klass* holder, int offset, JNIid* next);
1164   // Identifier lookup
1165   JNIid* find(int offset);
1166 
1167   bool find_local_field(fieldDescriptor* fd) {
1168     return InstanceKlass::cast(holder())->find_local_field_from_offset(offset(), true, fd);
1169   }
1170 
1171   static void deallocate(JNIid* id);
1172   // Debugging
1173 #ifdef ASSERT
1174   bool is_static_field_id() const { return _is_static_field_id; }
1175   void set_is_static_field_id()   { _is_static_field_id = true; }
1176 #endif
1177   void verify(Klass* holder);
1178 };
1179 
1180 
1181 // If breakpoints are more numerous than just JVMTI breakpoints,
1182 // consider compressing this data structure.
1183 // It is currently a simple linked list defined in method.hpp.
1184 
1185 class BreakpointInfo;
1186 
1187 
1188 // A collection point for interesting information about the previous
1189 // version(s) of an InstanceKlass.  A GrowableArray of PreviousVersionNodes
1190 // is attached to the InstanceKlass as needed. See PreviousVersionWalker below.
1191 class PreviousVersionNode : public CHeapObj<mtClass> {
1192  private:
1193   ConstantPool*    _prev_constant_pool;
1194 
1195   // If the previous version of the InstanceKlass doesn't have any
1196   // EMCP methods, then _prev_EMCP_methods will be NULL. If all the
1197   // EMCP methods have been collected, then _prev_EMCP_methods can
1198   // have a length of zero.
1199   GrowableArray<Method*>* _prev_EMCP_methods;
1200 
1201 public:
1202   PreviousVersionNode(ConstantPool* prev_constant_pool,
1203                       GrowableArray<Method*>* prev_EMCP_methods);
1204   ~PreviousVersionNode();
1205   ConstantPool* prev_constant_pool() const {
1206     return _prev_constant_pool;
1207   }
1208   GrowableArray<Method*>* prev_EMCP_methods() const {
1209     return _prev_EMCP_methods;
1210   }
1211 };
1212 
1213 
1214 // Helper object for walking previous versions.
1215 class PreviousVersionWalker : public StackObj {
1216  private:
1217   Thread*                               _thread;
1218   GrowableArray<PreviousVersionNode *>* _previous_versions;
1219   int                                   _current_index;
1220 
1221   // A pointer to the current node object so we can handle the deletes.
1222   PreviousVersionNode*                  _current_p;
1223 
1224   // The constant pool handle keeps all the methods in this class from being
1225   // deallocated from the metaspace during class unloading.
1226   constantPoolHandle                    _current_constant_pool_handle;
1227 
1228  public:
1229   PreviousVersionWalker(Thread* thread, InstanceKlass *ik);
1230 
1231   // Return the interesting information for the next previous version
1232   // of the klass. Returns NULL if there are no more previous versions.
1233   PreviousVersionNode* next_previous_version();
1234 };
1235 
1236 
1237 //
1238 // nmethodBucket is used to record dependent nmethods for
1239 // deoptimization.  nmethod dependencies are actually <klass, method>
1240 // pairs but we really only care about the klass part for purposes of
1241 // finding nmethods which might need to be deoptimized.  Instead of
1242 // recording the method, a count of how many times a particular nmethod
1243 // was recorded is kept.  This ensures that any recording errors are
1244 // noticed since an nmethod should be removed as many times are it's
1245 // added.
1246 //
1247 class nmethodBucket: public CHeapObj<mtClass> {
1248   friend class VMStructs;
1249  private:
1250   nmethod*       _nmethod;
1251   int            _count;
1252   nmethodBucket* _next;
1253 
1254  public:
1255   nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
1256     _nmethod = nmethod;
1257     _next = next;
1258     _count = 1;
1259   }
1260   int count()                             { return _count; }
1261   int increment()                         { _count += 1; return _count; }
1262   int decrement();
1263   nmethodBucket* next()                   { return _next; }
1264   void set_next(nmethodBucket* b)         { _next = b; }
1265   nmethod* get_nmethod()                  { return _nmethod; }
1266 };
1267 
1268 // An iterator that's used to access the inner classes indices in the
1269 // InstanceKlass::_inner_classes array.
1270 class InnerClassesIterator : public StackObj {
1271  private:
1272   Array<jushort>* _inner_classes;
1273   int _length;
1274   int _idx;
1275  public:
1276 
1277   InnerClassesIterator(instanceKlassHandle k) {
1278     _inner_classes = k->inner_classes();
1279     if (k->inner_classes() != NULL) {
1280       _length = _inner_classes->length();
1281       // The inner class array's length should be the multiple of
1282       // inner_class_next_offset if it only contains the InnerClasses
1283       // attribute data, or it should be
1284       // n*inner_class_next_offset+enclosing_method_attribute_size
1285       // if it also contains the EnclosingMethod data.
1286       assert((_length % InstanceKlass::inner_class_next_offset == 0 ||
1287               _length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size),
1288              "just checking");
1289       // Remove the enclosing_method portion if exists.
1290       if (_length % InstanceKlass::inner_class_next_offset == InstanceKlass::enclosing_method_attribute_size) {
1291         _length -= InstanceKlass::enclosing_method_attribute_size;
1292       }
1293     } else {
1294       _length = 0;
1295     }
1296     _idx = 0;
1297   }
1298 
1299   int length() const {
1300     return _length;
1301   }
1302 
1303   void next() {
1304     _idx += InstanceKlass::inner_class_next_offset;
1305   }
1306 
1307   bool done() const {
1308     return (_idx >= _length);
1309   }
1310 
1311   u2 inner_class_info_index() const {
1312     return _inner_classes->at(
1313                _idx + InstanceKlass::inner_class_inner_class_info_offset);
1314   }
1315 
1316   void set_inner_class_info_index(u2 index) {
1317     _inner_classes->at_put(
1318                _idx + InstanceKlass::inner_class_inner_class_info_offset, index);
1319   }
1320 
1321   u2 outer_class_info_index() const {
1322     return _inner_classes->at(
1323                _idx + InstanceKlass::inner_class_outer_class_info_offset);
1324   }
1325 
1326   void set_outer_class_info_index(u2 index) {
1327     _inner_classes->at_put(
1328                _idx + InstanceKlass::inner_class_outer_class_info_offset, index);
1329   }
1330 
1331   u2 inner_name_index() const {
1332     return _inner_classes->at(
1333                _idx + InstanceKlass::inner_class_inner_name_offset);
1334   }
1335 
1336   void set_inner_name_index(u2 index) {
1337     _inner_classes->at_put(
1338                _idx + InstanceKlass::inner_class_inner_name_offset, index);
1339   }
1340 
1341   u2 inner_access_flags() const {
1342     return _inner_classes->at(
1343                _idx + InstanceKlass::inner_class_access_flags_offset);
1344   }
1345 };
1346 
1347 #endif // SHARE_VM_OOPS_INSTANCEKLASS_HPP