1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
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  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).
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  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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  20  * or visit www.oracle.com if you need additional information or have any
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  24 
  25 #ifndef SHARE_OOPS_ARRAYKLASS_HPP
  26 #define SHARE_OOPS_ARRAYKLASS_HPP
  27 
  28 #include "memory/universe.hpp"
  29 #include "oops/klass.hpp"
  30 
  31 class fieldDescriptor;
  32 class klassVtable;
  33 
  34 // ArrayKlass is the abstract baseclass for all array classes
  35 
  36 class ArrayKlass: public Klass {
  37   friend class VMStructs;
  38  private:
  39   // If you add a new field that points to any metaspace object, you
  40   // must add this field to ArrayKlass::metaspace_pointers_do().
  41   int      _dimension;         // This is n'th-dimensional array.
  42   Klass* volatile _higher_dimension;  // Refers the (n+1)'th-dimensional array (if present).
  43   Klass* volatile _lower_dimension;   // Refers the (n-1)'th-dimensional array (if present).
  44 
  45  protected:
  46   Klass* _element_klass;            // The klass of the elements of this array type
  47                                     // The element type must be registered for both object arrays
  48                                     // (incl. object arrays with value type elements) and value type
  49                                     // arrays containing flattened value types. However, the element
  50                                     // type must not be registered for arrays of primitive types.
  51                                     // TODO: Update the class hierarchy so that element klass appears
  52                                     // only in array that contain non-primitive types.
  53   // Constructors
  54   // The constructor with the Symbol argument does the real array
  55   // initialization, the other is a dummy
  56   ArrayKlass(Symbol* name, KlassID id);
  57   ArrayKlass() { assert(DumpSharedSpaces || UseSharedSpaces, "only for cds"); }
  58 
  59   // Create array_name for element klass, creates a permanent symbol, returns result
  60   static Symbol* create_element_klass_array_name(bool is_qtype, Klass* element_klass, TRAPS);
  61 
  62  public:
  63   // Instance variables
  64   virtual Klass* element_klass() const      { return _element_klass; }
  65   virtual void set_element_klass(Klass* k)  { _element_klass = k; }
  66 
  67   // Compiler/Interpreter offset
  68   static ByteSize element_klass_offset() { return in_ByteSize(offset_of(ArrayKlass, _element_klass)); }
  69 
  70   // Presented with an ArrayKlass, which storage_properties should be encoded into arrayOop
  71   virtual ArrayStorageProperties storage_properties() { return ArrayStorageProperties::empty; }
  72 
  73   // Testing operation
  74   DEBUG_ONLY(bool is_array_klass_slow() const { return true; })
  75 
  76   // Instance variables
  77   int dimension() const                 { return _dimension;      }
  78   void set_dimension(int dimension)     { _dimension = dimension; }
  79 
  80   Klass* higher_dimension() const     { return _higher_dimension; }
  81   inline Klass* higher_dimension_acquire() const; // load with acquire semantics
  82   void set_higher_dimension(Klass* k) { _higher_dimension = k; }
  83   inline void release_set_higher_dimension(Klass* k); // store with release semantics
  84 
  85   Klass* lower_dimension() const      { return _lower_dimension; }
  86   void set_lower_dimension(Klass* k)  { _lower_dimension = k; }
  87 
  88   // offset of first element, including any padding for the sake of alignment
  89   int  array_header_in_bytes() const    { return layout_helper_header_size(layout_helper()); }
  90   int  log2_element_size() const        { return layout_helper_log2_element_size(layout_helper()); }
  91   // type of elements (T_OBJECT for both oop arrays and array-arrays)
  92   BasicType element_type() const        { return layout_helper_element_type(layout_helper()); }
  93 
  94   virtual InstanceKlass* java_super() const;//{ return SystemDictionary::Object_klass(); }
  95 
  96   // Allocation
  97   // Sizes points to the first dimension of the array, subsequent dimensions
  98   // are always in higher memory.  The callers of these set that up.
  99   virtual oop multi_allocate(int rank, jint* sizes, TRAPS);
 100   objArrayOop allocate_arrayArray(int n, int length, TRAPS);
 101 
 102   // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
 103   Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
 104 
 105   // Lookup operations
 106   Method* uncached_lookup_method(const Symbol* name,
 107                                  const Symbol* signature,
 108                                  OverpassLookupMode overpass_mode,
 109                                  PrivateLookupMode private_mode = find_private) const;
 110 
 111   static ArrayKlass* cast(Klass* k) {
 112     return const_cast<ArrayKlass*>(cast(const_cast<const Klass*>(k)));
 113   }
 114 
 115   static const ArrayKlass* cast(const Klass* k) {
 116     assert(k->is_array_klass(), "cast to ArrayKlass");
 117     return static_cast<const ArrayKlass*>(k);
 118   }
 119 
 120   GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
 121                                                   Array<InstanceKlass*>* transitive_interfaces);
 122 
 123   // Sizing
 124   static int static_size(int header_size);
 125 
 126   virtual void metaspace_pointers_do(MetaspaceClosure* iter);
 127 
 128 #if INCLUDE_SERVICES
 129   virtual void collect_statistics(KlassSizeStats *sz) const {
 130     Klass::collect_statistics(sz);
 131     // Do nothing for now, but remember to modify if you add new
 132     // stuff to ArrayKlass.
 133   }
 134 #endif
 135 
 136   // Iterators
 137   void array_klasses_do(void f(Klass* k));

 138 
 139   // Return a handle.
 140   static void     complete_create_array_klass(ArrayKlass* k, Klass* super_klass, ModuleEntry* module, TRAPS);
 141 
 142 
 143   // jvm support
 144   jint compute_modifier_flags(TRAPS) const;
 145 
 146   // JVMTI support
 147   jint jvmti_class_status() const;
 148 
 149   // CDS support - remove and restore oops from metadata. Oops are not shared.
 150   virtual void remove_unshareable_info();
 151   virtual void remove_java_mirror();
 152   virtual void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS);
 153 
 154   // Printing
 155   void print_on(outputStream* st) const;
 156   void print_value_on(outputStream* st) const;
 157 
 158   void oop_print_on(oop obj, outputStream* st);
 159 
 160   // Verification
 161   void verify_on(outputStream* st);
 162 
 163   void oop_verify_on(oop obj, outputStream* st);
 164 };
 165 
 166 #endif // SHARE_OOPS_ARRAYKLASS_HPP
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