1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
8 *
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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).
14 *
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23 */
24
25 #ifndef SHARE_OOPS_ARRAYKLASS_HPP
26 #define SHARE_OOPS_ARRAYKLASS_HPP
27
28 #include "oops/klass.hpp"
29
30 class fieldDescriptor;
31 class klassVtable;
32 class ObjArrayKlass;
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 const int _dimension; // This is n'th-dimensional array.
42 ObjArrayKlass* volatile _higher_dimension; // Refers the (n+1)'th-dimensional array (if present).
43 ArrayKlass* volatile _lower_dimension; // Refers the (n-1)'th-dimensional array (if present).
44
45 protected:
46 // Constructors
47 // The constructor with the Symbol argument does the real array
48 // initialization, the other is a dummy
49 ArrayKlass(int n, Symbol* name, KlassKind kind);
50 ArrayKlass();
51
52 public:
53 // Testing operation
54 DEBUG_ONLY(bool is_array_klass_slow() const override { return true; })
55
56 // Returns the ObjArrayKlass for n'th dimension.
57 ArrayKlass* array_klass(int n, TRAPS) override;
58 ArrayKlass* array_klass_or_null(int n) override;
59
60 // Returns the array class with this class as element type.
61 ArrayKlass* array_klass(TRAPS) override;
62 ArrayKlass* array_klass_or_null() override;
63
64 // Instance variables
65 int dimension() const { return _dimension; }
66
67 ObjArrayKlass* higher_dimension() const { return _higher_dimension; }
68 inline ObjArrayKlass* higher_dimension_acquire() const; // load with acquire semantics
69 void set_higher_dimension(ObjArrayKlass* k) { _higher_dimension = k; }
70 inline void release_set_higher_dimension(ObjArrayKlass* k); // store with release semantics
71
72 ArrayKlass* lower_dimension() const { return _lower_dimension; }
73 void set_lower_dimension(ArrayKlass* k) { _lower_dimension = k; }
74
75 // offset of first element, including any padding for the sake of alignment
76 int array_header_in_bytes() const { return layout_helper_header_size(layout_helper()); }
77 int log2_element_size() const { return layout_helper_log2_element_size(layout_helper()); }
78 // type of elements (T_OBJECT for both oop arrays and array-arrays)
79 BasicType element_type() const { return layout_helper_element_type(layout_helper()); }
80
81 InstanceKlass* java_super() const override;
82
83 // Allocation
84 // Sizes points to the first dimension of the array, subsequent dimensions
85 // are always in higher memory. The callers of these set that up.
86 virtual oop multi_allocate(int rank, jint* sizes, TRAPS);
87
88 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
89 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const override;
90
91 // Lookup operations
92 Method* uncached_lookup_method(const Symbol* name,
93 const Symbol* signature,
94 OverpassLookupMode overpass_mode,
95 PrivateLookupMode private_mode = PrivateLookupMode::find) const override;
96
97 static ArrayKlass* cast(Klass* k) {
98 return const_cast<ArrayKlass*>(cast(const_cast<const Klass*>(k)));
99 }
100
101 static const ArrayKlass* cast(const Klass* k) {
102 assert(k->is_array_klass(), "cast to ArrayKlass");
103 return static_cast<const ArrayKlass*>(k);
104 }
105
106 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
107 Array<InstanceKlass*>* transitive_interfaces) override;
108
109 // Sizing
110 static int static_size(int header_size);
111
112 void metaspace_pointers_do(MetaspaceClosure* iter) override;
113
114 // Return a handle.
115 static void complete_create_array_klass(ArrayKlass* k, Klass* super_klass, ModuleEntry* module, TRAPS);
116
117 // JVMTI support
118 jint jvmti_class_status() const override;
119
120 #if INCLUDE_CDS
121 // CDS support - remove and restore oops from metadata. Oops are not shared.
122 void remove_unshareable_info() override;
123 void remove_java_mirror() override;
124 void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS);
125 void cds_print_value_on(outputStream* st) const;
126 #endif
127
128 void log_array_class_load(Klass* k);
129 // Printing
130 void print_on(outputStream* st) const override;
131 void print_value_on(outputStream* st) const override;
132
133 void oop_print_on(oop obj, outputStream* st) override;
134
135 // Verification
136 void verify_on(outputStream* st) override;
137
138 void oop_verify_on(oop obj, outputStream* st) override;
139 };
140
141 #endif // SHARE_OOPS_ARRAYKLASS_HPP