1 /*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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