jdk/src/hotspot/share/oops/refArrayKlass.hpp

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#ifndef SHARE_OOPS_REFARRAYKLASS_HPP
#define SHARE_OOPS_REFARRAYKLASS_HPP

#include "oops/arrayKlass.hpp"
#include "oops/objArrayKlass.hpp"
#include "utilities/macros.hpp"

class ClassLoaderData;

// RefArrayKlass is the klass for arrays of references

class RefArrayKlass : public ObjArrayKlass {
  friend class Deoptimization;
  friend class oopFactory;
  friend class VMStructs;

 public:
  static const KlassKind Kind = RefArrayKlassKind;

 private:
  // Constructor
  RefArrayKlass(int n, Klass* element_klass, Symbol* name, ArrayProperties props);
  static RefArrayKlass* allocate_klass(ClassLoaderData* loader_data, int n, Klass* k, Symbol* name,
                                       ArrayProperties props, TRAPS);

 public:
  // For dummy objects
  RefArrayKlass() {}

  // Dispatched operation
  DEBUG_ONLY(bool is_refArray_klass_slow() const override { return true; })
  size_t oop_size(oop obj) const override;

  // Allocation
  static RefArrayKlass* allocate_refArray_klass(ClassLoaderData* loader_data,
                                                int n, Klass* element_klass,
                                                ArrayProperties props, TRAPS);

  objArrayOop allocate_instance(int length, TRAPS) override final;

  // Copying
  void copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) override;

  void metaspace_pointers_do(MetaspaceClosure* iter) override;

 private:
  // Either oop or narrowOop depending on UseCompressedOops.
  // must be called from within ObjArrayKlass.cpp
  void do_copy(arrayOop s, size_t src_offset,
               arrayOop d, size_t dst_offset,
               int length, TRAPS);

 public:
  static RefArrayKlass *cast(Klass* k) {
    assert(k->is_refArray_klass(), "cast to RefArrayKlass");
    return const_cast<RefArrayKlass *>(cast(const_cast<const Klass *>(k)));
  }

  static const RefArrayKlass *cast(const Klass* k) {
    assert(k->is_refArray_klass(), "cast to RefArrayKlass");
    return static_cast<const RefArrayKlass *>(k);
  }

  // Sizing
  static int header_size() { return sizeof(RefArrayKlass) / wordSize; }
  int size() const override { return ArrayKlass::static_size(header_size()); }

  // Initialization (virtual from Klass)
  void initialize(TRAPS) override;

  // Oop fields (and metadata) iterators
  //
  // The RefArrayKlass iterators also visits the Object's klass.

  // Iterate over oop elements and metadata.
  template <typename T, typename OopClosureType>
  inline void oop_oop_iterate(oop obj, OopClosureType* closure);

  // Iterate over oop elements and metadata.
  template <typename T, typename OopClosureType>
  inline void oop_oop_iterate_reverse(oop obj, OopClosureType* closure);

  // Iterate over oop elements within mr, and metadata.
  template <typename T, typename OopClosureType>
  inline void oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr);

  // Iterate over all oop elements, and no metadata.
  template <typename T, class OopClosureType>
  inline void oop_oop_iterate_elements(refArrayOop a, OopClosureType* closure);

  // Iterate over oop elements within index range [start, end), and no metadata.
  template <typename T, class OopClosureType>
  inline void oop_oop_iterate_elements_range(refArrayOop a, OopClosureType* closure, int start, int end);

 private:
  // Iterate over all oop elements bounded by addresses [low, high), and no metadata.
  template <typename T, class OopClosureType>
  inline void oop_oop_iterate_elements_bounded(refArrayOop a, OopClosureType* closure, void* low, void* high);

 public:
  // Printing
  void print_on(outputStream* st) const override;
  void print_value_on(outputStream* st) const override;

  void oop_print_value_on(oop obj, outputStream* st) override;
#ifndef PRODUCT
  void oop_print_on(oop obj, outputStream* st) override;
#endif // PRODUCT

  // Verification
  void verify_on(outputStream* st) override;

  void oop_verify_on(oop obj, outputStream* st) override;
};

#endif // SHARE_OOPS_REFARRAYKLASS_HPP