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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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#ifndef SHARE_OOPS_OBJARRAYOOP_HPP
#define SHARE_OOPS_OBJARRAYOOP_HPP

#include "oops/arrayOop.hpp"
#include "utilities/align.hpp"
#include <type_traits>

class Klass;

// An objArrayOop is an array containing oops.
// Evaluating "String arg[10]" will create an objArrayOop.

class objArrayOopDesc : public arrayOopDesc {
  friend class ArchiveHeapWriter;
  friend class ObjArrayKlass;
  friend class Runtime1;
  friend class psPromotionManager;
  friend class CSetMarkWordClosure;
  friend class Continuation;
  template <typename T>
  friend class RawOopWriter;

  template <class T> T* obj_at_addr(int index) const;

  template <class T>
  static ptrdiff_t obj_at_offset(int index) {
    return base_offset_in_bytes() + sizeof(T) * index;
  }

 public:
  // Returns the offset of the first element.
  static int base_offset_in_bytes() {
    return arrayOopDesc::base_offset_in_bytes(T_OBJECT);
  }

  // base is the address following the header.
  HeapWord* base() const;

  // Accessing
  oop obj_at(int index) const;

  void obj_at_put(int index, oop value);

  oop replace_if_null(int index, oop exchange_value);

  // Sizing
  size_t object_size()        { return object_size(length()); }

  static size_t object_size(int length) {
    // This returns the object size in HeapWords.
    size_t asz = (size_t)length * heapOopSize;
    size_t size_words = heap_word_size(base_offset_in_bytes() + asz);
    size_t osz = align_object_size(size_words);
    assert(osz < max_jint, "no overflow");
    return osz;
  }

  Klass* element_klass();

public:
  // special iterators for index ranges, returns size of object
  template <typename OopClosureType>
  void oop_iterate_range(OopClosureType* blk, int start, int end);
};

// See similar requirement for oopDesc.
static_assert(std::is_trivially_default_constructible<objArrayOopDesc>::value, "required");

#endif // SHARE_OOPS_OBJARRAYOOP_HPP