1 /*
2 * Copyright (c) 1997, 2021, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
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 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
24
25 #ifndef SHARE_OOPS_KLASS_HPP
26 #define SHARE_OOPS_KLASS_HPP
27
28 #include "memory/iterator.hpp"
29 #include "memory/memRegion.hpp"
30 #include "oops/markWord.hpp"
31 #include "oops/metadata.hpp"
32 #include "oops/oop.hpp"
33 #include "oops/oopHandle.hpp"
34 #include "utilities/accessFlags.hpp"
35 #include "utilities/macros.hpp"
36 #if INCLUDE_JFR
37 #include "jfr/support/jfrTraceIdExtension.hpp"
38 #endif
39
40 // Klass IDs for all subclasses of Klass
41 enum KlassID {
42 InstanceKlassID,
43 InstanceRefKlassID,
44 InstanceMirrorKlassID,
45 InstanceClassLoaderKlassID,
46 TypeArrayKlassID,
47 ObjArrayKlassID
48 };
49
50 const uint KLASS_ID_COUNT = 6;
51
52 //
53 // A Klass provides:
54 // 1: language level class object (method dictionary etc.)
55 // 2: provide vm dispatch behavior for the object
56 // Both functions are combined into one C++ class.
57
58 // One reason for the oop/klass dichotomy in the implementation is
59 // that we don't want a C++ vtbl pointer in every object. Thus,
60 // normal oops don't have any virtual functions. Instead, they
61 // forward all "virtual" functions to their klass, which does have
62 // a vtbl and does the C++ dispatch depending on the object's
63 // actual type. (See oop.inline.hpp for some of the forwarding code.)
64 // ALL FUNCTIONS IMPLEMENTING THIS DISPATCH ARE PREFIXED WITH "oop_"!
65
66 // Forward declarations.
67 template <class T> class Array;
68 template <class T> class GrowableArray;
69 class ClassLoaderData;
70 class fieldDescriptor;
71 class klassVtable;
72 class ModuleEntry;
73 class PackageEntry;
74 class ParCompactionManager;
75 class PSPromotionManager;
76 class vtableEntry;
77
78 class Klass : public Metadata {
79 friend class VMStructs;
80 friend class JVMCIVMStructs;
81 protected:
82 // If you add a new field that points to any metaspace object, you
83 // must add this field to Klass::metaspace_pointers_do().
84
85 // note: put frequently-used fields together at start of klass structure
86 // for better cache behavior (may not make much of a difference but sure won't hurt)
87 enum { _primary_super_limit = 8 };
88
89 // The "layout helper" is a combined descriptor of object layout.
90 // For klasses which are neither instance nor array, the value is zero.
91 //
92 // For instances, layout helper is a positive number, the instance size.
93 // This size is already passed through align_object_size and scaled to bytes.
94 // The low order bit is set if instances of this class cannot be
95 // allocated using the fastpath.
96 //
97 // For arrays, layout helper is a negative number, containing four
98 // distinct bytes, as follows:
99 // MSB:[tag, hsz, ebt, log2(esz)]:LSB
100 // where:
101 // tag is 0x80 if the elements are oops, 0xC0 if non-oops
102 // hsz is array header size in bytes (i.e., offset of first element)
103 // ebt is the BasicType of the elements
104 // esz is the element size in bytes
105 // This packed word is arranged so as to be quickly unpacked by the
106 // various fast paths that use the various subfields.
107 //
108 // The esz bits can be used directly by a SLL instruction, without masking.
109 //
110 // Note that the array-kind tag looks like 0x00 for instance klasses,
111 // since their length in bytes is always less than 24Mb.
112 //
113 // Final note: This comes first, immediately after C++ vtable,
114 // because it is frequently queried.
115 jint _layout_helper;
116
117 // Klass identifier used to implement devirtualized oop closure dispatching.
118 const KlassID _id;
119
120 // vtable length
121 int _vtable_len;
122
123 // The fields _super_check_offset, _secondary_super_cache, _secondary_supers
124 // and _primary_supers all help make fast subtype checks. See big discussion
125 // in doc/server_compiler/checktype.txt
126 //
127 // Where to look to observe a supertype (it is &_secondary_super_cache for
128 // secondary supers, else is &_primary_supers[depth()].
129 juint _super_check_offset;
130
131 // Class name. Instance classes: java/lang/String, etc. Array classes: [I,
132 // [Ljava/lang/String;, etc. Set to zero for all other kinds of classes.
133 Symbol* _name;
134
135 // Cache of last observed secondary supertype
136 Klass* _secondary_super_cache;
137 // Array of all secondary supertypes
138 Array<Klass*>* _secondary_supers;
139 // Ordered list of all primary supertypes
140 Klass* _primary_supers[_primary_super_limit];
141 // java/lang/Class instance mirroring this class
142 OopHandle _java_mirror;
143 // Superclass
144 Klass* _super;
145 // First subclass (NULL if none); _subklass->next_sibling() is next one
146 Klass* volatile _subklass;
147 // Sibling link (or NULL); links all subklasses of a klass
148 Klass* volatile _next_sibling;
149
150 // All klasses loaded by a class loader are chained through these links
151 Klass* _next_link;
152
153 // The VM's representation of the ClassLoader used to load this class.
154 // Provide access the corresponding instance java.lang.ClassLoader.
155 ClassLoaderData* _class_loader_data;
156
157 jint _modifier_flags; // Processed access flags, for use by Class.getModifiers.
158 AccessFlags _access_flags; // Access flags. The class/interface distinction is stored here.
159
160 JFR_ONLY(DEFINE_TRACE_ID_FIELD;)
161
162 private:
163 // This is an index into FileMapHeader::_shared_path_table[], to
164 // associate this class with the JAR file where it's loaded from during
165 // dump time. If a class is not loaded from the shared archive, this field is
166 // -1.
167 jshort _shared_class_path_index;
168
169 #if INCLUDE_CDS
170 // Flags of the current shared class.
171 u2 _shared_class_flags;
172 enum {
173 _archived_lambda_proxy_is_available = 2,
174 _has_value_based_class_annotation = 4,
175 _verified_at_dump_time = 8
176 };
177 #endif
178
179 CDS_JAVA_HEAP_ONLY(int _archived_mirror_index;)
180
181 protected:
182
183 // Constructor
184 Klass(KlassID id);
185 Klass() : _id(KlassID(-1)) { assert(DumpSharedSpaces || UseSharedSpaces, "only for cds"); }
186
187 void* operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw();
188
189 public:
190 int id() { return _id; }
191
192 enum class DefaultsLookupMode { find, skip };
193 enum class OverpassLookupMode { find, skip };
194 enum class StaticLookupMode { find, skip };
195 enum class PrivateLookupMode { find, skip };
196
197 virtual bool is_klass() const { return true; }
198
199 // super() cannot be InstanceKlass* -- Java arrays are covariant, and _super is used
200 // to implement that. NB: the _super of "[Ljava/lang/Integer;" is "[Ljava/lang/Number;"
201 // If this is not what your code expects, you're probably looking for Klass::java_super().
202 Klass* super() const { return _super; }
203 void set_super(Klass* k) { _super = k; }
204
205 // initializes _super link, _primary_supers & _secondary_supers arrays
206 void initialize_supers(Klass* k, Array<InstanceKlass*>* transitive_interfaces, TRAPS);
207
208 // klass-specific helper for initializing _secondary_supers
209 virtual GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
210 Array<InstanceKlass*>* transitive_interfaces);
211
212 // java_super is the Java-level super type as specified by Class.getSuperClass.
213 virtual InstanceKlass* java_super() const { return NULL; }
214
215 juint super_check_offset() const { return _super_check_offset; }
216 void set_super_check_offset(juint o) { _super_check_offset = o; }
217
218 Klass* secondary_super_cache() const { return _secondary_super_cache; }
219 void set_secondary_super_cache(Klass* k) { _secondary_super_cache = k; }
220
221 Array<Klass*>* secondary_supers() const { return _secondary_supers; }
222 void set_secondary_supers(Array<Klass*>* k) { _secondary_supers = k; }
223
224 // Return the element of the _super chain of the given depth.
225 // If there is no such element, return either NULL or this.
226 Klass* primary_super_of_depth(juint i) const {
227 assert(i < primary_super_limit(), "oob");
228 Klass* super = _primary_supers[i];
229 assert(super == NULL || super->super_depth() == i, "correct display");
230 return super;
231 }
232
233 // Can this klass be a primary super? False for interfaces and arrays of
234 // interfaces. False also for arrays or classes with long super chains.
235 bool can_be_primary_super() const {
236 const juint secondary_offset = in_bytes(secondary_super_cache_offset());
237 return super_check_offset() != secondary_offset;
238 }
239 virtual bool can_be_primary_super_slow() const;
240
241 // Returns number of primary supers; may be a number in the inclusive range [0, primary_super_limit].
242 juint super_depth() const {
243 if (!can_be_primary_super()) {
244 return primary_super_limit();
245 } else {
246 juint d = (super_check_offset() - in_bytes(primary_supers_offset())) / sizeof(Klass*);
247 assert(d < primary_super_limit(), "oob");
248 assert(_primary_supers[d] == this, "proper init");
249 return d;
250 }
251 }
252
253 // java mirror
254 oop java_mirror() const;
255 oop java_mirror_no_keepalive() const;
256 void set_java_mirror(Handle m);
257
258 oop archived_java_mirror() NOT_CDS_JAVA_HEAP_RETURN_(NULL);
259 void set_archived_java_mirror(oop m) NOT_CDS_JAVA_HEAP_RETURN;
260
261 // Temporary mirror switch used by RedefineClasses
262 void replace_java_mirror(oop mirror);
263
264 // Set java mirror OopHandle to NULL for CDS
265 // This leaves the OopHandle in the CLD, but that's ok, you can't release them.
266 void clear_java_mirror_handle() { _java_mirror = OopHandle(); }
267
268 // modifier flags
269 jint modifier_flags() const { return _modifier_flags; }
270 void set_modifier_flags(jint flags) { _modifier_flags = flags; }
271
272 // size helper
273 int layout_helper() const { return _layout_helper; }
274 void set_layout_helper(int lh) { _layout_helper = lh; }
275
276 // Note: for instances layout_helper() may include padding.
277 // Use InstanceKlass::contains_field_offset to classify field offsets.
278
279 // sub/superklass links
280 Klass* subklass(bool log = false) const;
281 Klass* next_sibling(bool log = false) const;
282
283 InstanceKlass* superklass() const;
284 void append_to_sibling_list(); // add newly created receiver to superklass' subklass list
285
286 void set_next_link(Klass* k) { _next_link = k; }
287 Klass* next_link() const { return _next_link; } // The next klass defined by the class loader.
288 Klass** next_link_addr() { return &_next_link; }
289
290 // class loader data
291 ClassLoaderData* class_loader_data() const { return _class_loader_data; }
292 void set_class_loader_data(ClassLoaderData* loader_data) { _class_loader_data = loader_data; }
293
294 int shared_classpath_index() const {
295 return _shared_class_path_index;
296 };
297
298 void set_shared_classpath_index(int index) {
299 _shared_class_path_index = index;
300 };
301
302 bool has_archived_mirror_index() const {
303 CDS_JAVA_HEAP_ONLY(return _archived_mirror_index >= 0;)
304 NOT_CDS_JAVA_HEAP(return false);
305 }
306
307 void clear_archived_mirror_index() NOT_CDS_JAVA_HEAP_RETURN;
308
309 void set_lambda_proxy_is_available() {
310 CDS_ONLY(_shared_class_flags |= _archived_lambda_proxy_is_available;)
311 }
312 void clear_lambda_proxy_is_available() {
313 CDS_ONLY(_shared_class_flags &= ~_archived_lambda_proxy_is_available;)
314 }
315 bool lambda_proxy_is_available() const {
316 CDS_ONLY(return (_shared_class_flags & _archived_lambda_proxy_is_available) != 0;)
317 NOT_CDS(return false;)
318 }
319
320 void set_has_value_based_class_annotation() {
321 CDS_ONLY(_shared_class_flags |= _has_value_based_class_annotation;)
322 }
323 void clear_has_value_based_class_annotation() {
324 CDS_ONLY(_shared_class_flags &= ~_has_value_based_class_annotation;)
325 }
326 bool has_value_based_class_annotation() const {
327 CDS_ONLY(return (_shared_class_flags & _has_value_based_class_annotation) != 0;)
328 NOT_CDS(return false;)
329 }
330
331 void set_verified_at_dump_time() {
332 CDS_ONLY(_shared_class_flags |= _verified_at_dump_time;)
333 }
334 bool verified_at_dump_time() const {
335 CDS_ONLY(return (_shared_class_flags & _verified_at_dump_time) != 0;)
336 NOT_CDS(return false;)
337 }
338
339
340 // Obtain the module or package for this class
341 virtual ModuleEntry* module() const = 0;
342 virtual PackageEntry* package() const = 0;
343
344 protected: // internal accessors
345 void set_subklass(Klass* s);
346 void set_next_sibling(Klass* s);
347
348 public:
349
350 // Compiler support
351 static ByteSize super_offset() { return in_ByteSize(offset_of(Klass, _super)); }
352 static ByteSize super_check_offset_offset() { return in_ByteSize(offset_of(Klass, _super_check_offset)); }
353 static ByteSize primary_supers_offset() { return in_ByteSize(offset_of(Klass, _primary_supers)); }
354 static ByteSize secondary_super_cache_offset() { return in_ByteSize(offset_of(Klass, _secondary_super_cache)); }
355 static ByteSize secondary_supers_offset() { return in_ByteSize(offset_of(Klass, _secondary_supers)); }
356 static ByteSize java_mirror_offset() { return in_ByteSize(offset_of(Klass, _java_mirror)); }
357 static ByteSize class_loader_data_offset() { return in_ByteSize(offset_of(Klass, _class_loader_data)); }
358 static ByteSize modifier_flags_offset() { return in_ByteSize(offset_of(Klass, _modifier_flags)); }
359 static ByteSize layout_helper_offset() { return in_ByteSize(offset_of(Klass, _layout_helper)); }
360 static ByteSize access_flags_offset() { return in_ByteSize(offset_of(Klass, _access_flags)); }
361
362 // Unpacking layout_helper:
363 static const int _lh_neutral_value = 0; // neutral non-array non-instance value
364 static const int _lh_instance_slow_path_bit = 0x01;
365 static const int _lh_log2_element_size_shift = BitsPerByte*0;
366 static const int _lh_log2_element_size_mask = BitsPerLong-1;
367 static const int _lh_element_type_shift = BitsPerByte*1;
368 static const int _lh_element_type_mask = right_n_bits(BitsPerByte); // shifted mask
369 static const int _lh_header_size_shift = BitsPerByte*2;
370 static const int _lh_header_size_mask = right_n_bits(BitsPerByte); // shifted mask
371 static const int _lh_array_tag_bits = 2;
372 static const int _lh_array_tag_shift = BitsPerInt - _lh_array_tag_bits;
373 static const int _lh_array_tag_obj_value = ~0x01; // 0x80000000 >> 30
374
375 static const unsigned int _lh_array_tag_type_value = 0Xffffffff; // ~0x00, // 0xC0000000 >> 30
376
377 static int layout_helper_size_in_bytes(jint lh) {
378 assert(lh > (jint)_lh_neutral_value, "must be instance");
379 return (int) lh & ~_lh_instance_slow_path_bit;
380 }
381 static bool layout_helper_needs_slow_path(jint lh) {
382 assert(lh > (jint)_lh_neutral_value, "must be instance");
383 return (lh & _lh_instance_slow_path_bit) != 0;
384 }
385 static bool layout_helper_is_instance(jint lh) {
386 return (jint)lh > (jint)_lh_neutral_value;
387 }
388 static bool layout_helper_is_array(jint lh) {
389 return (jint)lh < (jint)_lh_neutral_value;
390 }
391 static bool layout_helper_is_typeArray(jint lh) {
392 // _lh_array_tag_type_value == (lh >> _lh_array_tag_shift);
393 return (juint)lh >= (juint)(_lh_array_tag_type_value << _lh_array_tag_shift);
394 }
395 static bool layout_helper_is_objArray(jint lh) {
396 // _lh_array_tag_obj_value == (lh >> _lh_array_tag_shift);
397 return (jint)lh < (jint)(_lh_array_tag_type_value << _lh_array_tag_shift);
398 }
399 static int layout_helper_header_size(jint lh) {
400 assert(lh < (jint)_lh_neutral_value, "must be array");
401 int hsize = (lh >> _lh_header_size_shift) & _lh_header_size_mask;
402 assert(hsize > 0 && hsize < (int)sizeof(oopDesc)*3, "sanity");
403 return hsize;
404 }
405 static BasicType layout_helper_element_type(jint lh) {
406 assert(lh < (jint)_lh_neutral_value, "must be array");
407 int btvalue = (lh >> _lh_element_type_shift) & _lh_element_type_mask;
408 assert(btvalue >= T_BOOLEAN && btvalue <= T_OBJECT, "sanity");
409 return (BasicType) btvalue;
410 }
411
412 // Want a pattern to quickly diff against layout header in register
413 // find something less clever!
414 static int layout_helper_boolean_diffbit() {
415 jint zlh = array_layout_helper(T_BOOLEAN);
416 jint blh = array_layout_helper(T_BYTE);
417 assert(zlh != blh, "array layout helpers must differ");
418 int diffbit = 1;
419 while ((diffbit & (zlh ^ blh)) == 0 && (diffbit & zlh) == 0) {
420 diffbit <<= 1;
421 assert(diffbit != 0, "make sure T_BOOLEAN has a different bit than T_BYTE");
422 }
423 return diffbit;
424 }
425
426 static int layout_helper_log2_element_size(jint lh) {
427 assert(lh < (jint)_lh_neutral_value, "must be array");
428 int l2esz = (lh >> _lh_log2_element_size_shift) & _lh_log2_element_size_mask;
429 assert(l2esz <= LogBytesPerLong,
430 "sanity. l2esz: 0x%x for lh: 0x%x", (uint)l2esz, (uint)lh);
431 return l2esz;
432 }
433 static jint array_layout_helper(jint tag, int hsize, BasicType etype, int log2_esize) {
434 return (tag << _lh_array_tag_shift)
435 | (hsize << _lh_header_size_shift)
436 | ((int)etype << _lh_element_type_shift)
437 | (log2_esize << _lh_log2_element_size_shift);
438 }
439 static jint instance_layout_helper(jint size, bool slow_path_flag) {
440 return (size << LogBytesPerWord)
441 | (slow_path_flag ? _lh_instance_slow_path_bit : 0);
442 }
443 static int layout_helper_to_size_helper(jint lh) {
444 assert(lh > (jint)_lh_neutral_value, "must be instance");
445 // Note that the following expression discards _lh_instance_slow_path_bit.
446 return lh >> LogBytesPerWord;
447 }
448 // Out-of-line version computes everything based on the etype:
449 static jint array_layout_helper(BasicType etype);
450
451 // What is the maximum number of primary superclasses any klass can have?
452 static juint primary_super_limit() { return _primary_super_limit; }
453
454 // vtables
455 klassVtable vtable() const;
456 int vtable_length() const { return _vtable_len; }
457
458 // subclass check
459 bool is_subclass_of(const Klass* k) const;
460 // subtype check: true if is_subclass_of, or if k is interface and receiver implements it
461 bool is_subtype_of(Klass* k) const {
462 juint off = k->super_check_offset();
463 Klass* sup = *(Klass**)( (address)this + off );
464 const juint secondary_offset = in_bytes(secondary_super_cache_offset());
465 if (sup == k) {
466 return true;
467 } else if (off != secondary_offset) {
468 return false;
469 } else {
470 return search_secondary_supers(k);
471 }
472 }
473
474 bool search_secondary_supers(Klass* k) const;
475
476 // Find LCA in class hierarchy
477 Klass *LCA( Klass *k );
478
479 // Check whether reflection/jni/jvm code is allowed to instantiate this class;
480 // if not, throw either an Error or an Exception.
481 virtual void check_valid_for_instantiation(bool throwError, TRAPS);
482
483 // array copying
484 virtual void copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS);
485
486 // tells if the class should be initialized
487 virtual bool should_be_initialized() const { return false; }
488 // initializes the klass
489 virtual void initialize(TRAPS);
490 virtual Klass* find_field(Symbol* name, Symbol* signature, fieldDescriptor* fd) const;
491 virtual Method* uncached_lookup_method(const Symbol* name, const Symbol* signature,
492 OverpassLookupMode overpass_mode,
493 PrivateLookupMode = PrivateLookupMode::find) const;
494 public:
495 Method* lookup_method(const Symbol* name, const Symbol* signature) const {
496 return uncached_lookup_method(name, signature, OverpassLookupMode::find);
497 }
498
499 // array class with specific rank
500 virtual Klass* array_klass(int rank, TRAPS) = 0;
501
502 // array class with this klass as element type
503 virtual Klass* array_klass(TRAPS) = 0;
504
505 // These will return NULL instead of allocating on the heap:
506 virtual Klass* array_klass_or_null(int rank) = 0;
507 virtual Klass* array_klass_or_null() = 0;
508
509 virtual oop protection_domain() const = 0;
510
511 oop class_loader() const;
512
513 inline oop klass_holder() const;
514
515 protected:
516
517 // Error handling when length > max_length or length < 0
518 static void check_array_allocation_length(int length, int max_length, TRAPS);
519
520 void set_vtable_length(int len) { _vtable_len= len; }
521
522 vtableEntry* start_of_vtable() const;
523 void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS);
524 public:
525 Method* method_at_vtable(int index);
526
527 static ByteSize vtable_start_offset();
528 static ByteSize vtable_length_offset() {
529 return byte_offset_of(Klass, _vtable_len);
530 }
531
532 // CDS support - remove and restore oops from metadata. Oops are not shared.
533 virtual void remove_unshareable_info();
534 virtual void remove_java_mirror();
535
536 bool is_unshareable_info_restored() const {
537 assert(is_shared(), "use this for shared classes only");
538 if (has_archived_mirror_index()) {
539 // _java_mirror is not a valid OopHandle but rather an encoded reference in the shared heap
540 return false;
541 } else if (_java_mirror.ptr_raw() == NULL) {
542 return false;
543 } else {
544 return true;
545 }
546 }
547
548 public:
549 // ALL FUNCTIONS BELOW THIS POINT ARE DISPATCHED FROM AN OOP
550 // These functions describe behavior for the oop not the KLASS.
551
552 // actual oop size of obj in memory in word size.
553 virtual size_t oop_size(oop obj) const = 0;
554
555 // Size of klass in word size.
556 virtual int size() const = 0;
557
558 // Returns the Java name for a class (Resource allocated)
559 // For arrays, this returns the name of the element with a leading '['.
560 // For classes, this returns the name with the package separators
561 // turned into '.'s.
562 const char* external_name() const;
563 // Returns the name for a class (Resource allocated) as the class
564 // would appear in a signature.
565 // For arrays, this returns the name of the element with a leading '['.
566 // For classes, this returns the name with a leading 'L' and a trailing ';'
567 // and the package separators as '/'.
568 virtual const char* signature_name() const;
569
570 const char* joint_in_module_of_loader(const Klass* class2, bool include_parent_loader = false) const;
571 const char* class_in_module_of_loader(bool use_are = false, bool include_parent_loader = false) const;
572
573 // Returns "interface", "abstract class" or "class".
574 const char* external_kind() const;
575
576 // type testing operations
577 #ifdef ASSERT
578 protected:
579 virtual bool is_instance_klass_slow() const { return false; }
580 virtual bool is_array_klass_slow() const { return false; }
581 virtual bool is_objArray_klass_slow() const { return false; }
582 virtual bool is_typeArray_klass_slow() const { return false; }
583 #endif // ASSERT
584 public:
585
586 // Fast non-virtual versions
587 #ifndef ASSERT
588 #define assert_same_query(xval, xcheck) xval
589 #else
590 private:
591 static bool assert_same_query(bool xval, bool xslow) {
592 assert(xval == xslow, "slow and fast queries agree");
593 return xval;
594 }
595 public:
596 #endif
597 inline bool is_instance_klass() const { return assert_same_query(
598 layout_helper_is_instance(layout_helper()),
599 is_instance_klass_slow()); }
600 inline bool is_array_klass() const { return assert_same_query(
601 layout_helper_is_array(layout_helper()),
602 is_array_klass_slow()); }
603 inline bool is_objArray_klass() const { return assert_same_query(
604 layout_helper_is_objArray(layout_helper()),
605 is_objArray_klass_slow()); }
606 inline bool is_typeArray_klass() const { return assert_same_query(
607 layout_helper_is_typeArray(layout_helper()),
608 is_typeArray_klass_slow()); }
609 #undef assert_same_query
610
611 // Access flags
612 AccessFlags access_flags() const { return _access_flags; }
613 void set_access_flags(AccessFlags flags) { _access_flags = flags; }
614
615 bool is_public() const { return _access_flags.is_public(); }
616 bool is_final() const { return _access_flags.is_final(); }
617 bool is_interface() const { return _access_flags.is_interface(); }
618 bool is_abstract() const { return _access_flags.is_abstract(); }
619 bool is_super() const { return _access_flags.is_super(); }
620 bool is_synthetic() const { return _access_flags.is_synthetic(); }
621 void set_is_synthetic() { _access_flags.set_is_synthetic(); }
622 bool has_finalizer() const { return _access_flags.has_finalizer(); }
623 bool has_final_method() const { return _access_flags.has_final_method(); }
624 void set_has_finalizer() { _access_flags.set_has_finalizer(); }
625 void set_has_final_method() { _access_flags.set_has_final_method(); }
626 bool has_vanilla_constructor() const { return _access_flags.has_vanilla_constructor(); }
627 void set_has_vanilla_constructor() { _access_flags.set_has_vanilla_constructor(); }
628 bool has_miranda_methods () const { return access_flags().has_miranda_methods(); }
629 void set_has_miranda_methods() { _access_flags.set_has_miranda_methods(); }
630 bool is_shared() const { return access_flags().is_shared_class(); } // shadows MetaspaceObj::is_shared)()
631 void set_is_shared() { _access_flags.set_is_shared_class(); }
632 bool is_hidden() const { return access_flags().is_hidden_class(); }
633 void set_is_hidden() { _access_flags.set_is_hidden_class(); }
634 bool is_value_based() { return _access_flags.is_value_based_class(); }
635 void set_is_value_based() { _access_flags.set_is_value_based_class(); }
636
637 inline bool is_non_strong_hidden() const;
638
639 bool is_cloneable() const;
640 void set_is_cloneable();
641
642 JFR_ONLY(DEFINE_TRACE_ID_METHODS;)
643
644 virtual void metaspace_pointers_do(MetaspaceClosure* iter);
645 virtual MetaspaceObj::Type type() const { return ClassType; }
646
647 inline bool is_loader_alive() const;
648
649 void clean_subklass();
650
651 static void clean_weak_klass_links(bool unloading_occurred, bool clean_alive_klasses = true);
652 static void clean_subklass_tree() {
653 clean_weak_klass_links(/*unloading_occurred*/ true , /* clean_alive_klasses */ false);
654 }
655
656 // Return self, except for abstract classes with exactly 1
657 // implementor. Then return the 1 concrete implementation.
658 Klass *up_cast_abstract();
659
660 // klass name
661 Symbol* name() const { return _name; }
662 void set_name(Symbol* n);
663
664 virtual void release_C_heap_structures(bool release_constant_pool = true);
665
666 public:
667 virtual jint compute_modifier_flags() const = 0;
668
669 // JVMTI support
670 virtual jint jvmti_class_status() const;
671
672 // Printing
673 virtual void print_on(outputStream* st) const;
674
675 virtual void oop_print_value_on(oop obj, outputStream* st);
676 virtual void oop_print_on (oop obj, outputStream* st);
677
678 virtual const char* internal_name() const = 0;
679
680 // Verification
681 virtual void verify_on(outputStream* st);
682 void verify() { verify_on(tty); }
683
684 #ifndef PRODUCT
685 bool verify_vtable_index(int index);
686 #endif
687
688 virtual void oop_verify_on(oop obj, outputStream* st);
689
690 // for error reporting
691 static bool is_valid(Klass* k);
692 };
693
694 #endif // SHARE_OOPS_KLASS_HPP