1 /*
2 * Copyright (c) 1997, 2026, 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.
22 *
23 */
24
25 #include "classfile/vmSymbols.hpp"
26 #include "memory/resourceArea.hpp"
27 #include "oops/annotations.hpp"
28 #include "oops/constantPool.hpp"
29 #include "oops/fieldStreams.inline.hpp"
30 #include "oops/instanceKlass.hpp"
31 #include "oops/klass.inline.hpp"
32 #include "oops/oop.inline.hpp"
33 #include "runtime/fieldDescriptor.inline.hpp"
34 #include "runtime/handles.inline.hpp"
35 #include "runtime/signature.hpp"
36
37 Symbol* fieldDescriptor::generic_signature() const {
38 if (!has_generic_signature()) {
39 return nullptr;
40 }
41 return _cp->symbol_at(_fieldinfo.generic_signature_index());
42 }
43
44 bool fieldDescriptor::is_trusted_final() const {
45 InstanceKlass* ik = field_holder();
46 return is_final() && (is_static() || ik->is_hidden() || ik->is_record());
47 }
48
49 bool fieldDescriptor::is_mutable_static_final() const {
50 InstanceKlass* ik = field_holder();
51 // write protected fields (JLS 17.5.4)
52 if (is_final() && is_static() && ik == vmClasses::System_klass() &&
53 (offset() == java_lang_System::in_offset() || offset() == java_lang_System::out_offset() || offset() == java_lang_System::err_offset())) {
54 return true;
55 }
56 return false;
57 }
58
59 AnnotationArray* fieldDescriptor::annotations() const {
60 InstanceKlass* ik = field_holder();
61 Array<AnnotationArray*>* md = ik->fields_annotations();
62 if (md == nullptr)
63 return nullptr;
64 return md->at(index());
65 }
66
67 AnnotationArray* fieldDescriptor::type_annotations() const {
68 InstanceKlass* ik = field_holder();
69 Array<AnnotationArray*>* type_annos = ik->fields_type_annotations();
70 if (type_annos == nullptr)
71 return nullptr;
72 return type_annos->at(index());
73 }
74
75 constantTag fieldDescriptor::initial_value_tag() const {
76 return constants()->tag_at(initial_value_index());
77 }
78
79 jint fieldDescriptor::int_initial_value() const {
80 return constants()->int_at(initial_value_index());
81 }
82
83 jlong fieldDescriptor::long_initial_value() const {
84 return constants()->long_at(initial_value_index());
85 }
86
87 jfloat fieldDescriptor::float_initial_value() const {
88 return constants()->float_at(initial_value_index());
89 }
90
91 jdouble fieldDescriptor::double_initial_value() const {
92 return constants()->double_at(initial_value_index());
93 }
94
95 oop fieldDescriptor::string_initial_value(TRAPS) const {
96 return constants()->uncached_string_at(initial_value_index(), THREAD);
97 }
98
99 void fieldDescriptor::reinitialize(InstanceKlass* ik, const FieldInfo& fieldinfo) {
100 if (_cp.is_null() || field_holder() != ik) {
101 _cp = constantPoolHandle(Thread::current(), ik->constants());
102 // _cp should now reference ik's constant pool; i.e., ik is now field_holder.
103 // If the class is a scratch class, the constant pool points to the original class,
104 // but that's ok because of constant pool merging.
105 assert(field_holder() == ik || ik->is_scratch_class(), "must be already initialized to this class");
106 }
107 _fieldinfo = fieldinfo;
108 guarantee(_fieldinfo.name_index() != 0 && _fieldinfo.signature_index() != 0, "bad constant pool index for fieldDescriptor");
109 }
110
111 void fieldDescriptor::print_access_flags(outputStream* st) const {
112 AccessFlags flags = access_flags();
113 if (flags.is_public ()) st->print("public ");
114 if (flags.is_private ()) st->print("private ");
115 if (flags.is_protected()) st->print("protected ");
116 if (flags.is_static ()) st->print("static ");
117 if (flags.is_final ()) st->print("final ");
118 if (flags.is_volatile ()) st->print("volatile ");
119 if (flags.is_transient()) st->print("transient ");
120 if (flags.is_enum ()) st->print("enum ");
121 if (flags.is_synthetic()) st->print("synthetic ");
122 }
123
124 void fieldDescriptor::print_on(outputStream* st) const {
125 print_access_flags(st);
126 if (field_flags().is_injected()) st->print("injected ");
127 name()->print_value_on(st);
128 st->print(" ");
129 signature()->print_value_on(st);
130 st->print(" @%d ", offset());
131 if (WizardMode && has_initial_value()) {
132 st->print("(initval ");
133 constantTag t = initial_value_tag();
134 if (t.is_int()) {
135 st->print("int %d)", int_initial_value());
136 } else if (t.is_long()){
137 st->print_jlong(long_initial_value());
138 } else if (t.is_float()){
139 st->print("float %f)", float_initial_value());
140 } else if (t.is_double()){
141 st->print("double %lf)", double_initial_value());
142 }
143 }
144 }
145
146 void fieldDescriptor::print() const { print_on(tty); }
147
148 void fieldDescriptor::print_on_for(outputStream* st, oop obj) {
149 print_on(st);
150 st->print(" ");
151
152 BasicType ft = field_type();
153 switch (ft) {
154 case T_BYTE:
155 st->print("%d", obj->byte_field(offset()));
156 break;
157 case T_CHAR:
158 {
159 jchar c = obj->char_field(offset());
160 st->print("%c %d", isprint(c) ? c : ' ', c);
161 }
162 break;
163 case T_DOUBLE:
164 st->print("%lf", obj->double_field(offset()));
165 break;
166 case T_FLOAT:
167 st->print("%f", obj->float_field(offset()));
168 break;
169 case T_INT:
170 st->print("%d", obj->int_field(offset()));
171 break;
172 case T_LONG:
173 st->print_jlong(obj->long_field(offset()));
174 break;
175 case T_SHORT:
176 st->print("%d", obj->short_field(offset()));
177 break;
178 case T_BOOLEAN:
179 st->print("%s", obj->bool_field(offset()) ? "true" : "false");
180 break;
181 case T_ARRAY:
182 if (obj->obj_field(offset()) != nullptr) {
183 obj->obj_field(offset())->print_value_on(st);
184 } else {
185 st->print("null");
186 }
187 break;
188 case T_OBJECT:
189 if (obj->obj_field(offset()) != nullptr) {
190 obj->obj_field(offset())->print_value_on(st);
191 } else {
192 st->print("null");
193 }
194 break;
195 default:
196 ShouldNotReachHere();
197 break;
198 }
199
200 // Print a hint as to the underlying integer representation.
201 if (is_reference_type(ft)) {
202 #ifdef _LP64
203 if (UseCompressedOops) {
204 st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset()));
205 } else {
206 st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset()));
207 }
208 #else
209 st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset()));
210 #endif
211 } else { // Primitives
212 switch (ft) {
213 case T_LONG: st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset())); break;
214 case T_DOUBLE: st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset())); break;
215 case T_BYTE: st->print(" (" INT8_FORMAT_X_0 ")", obj->byte_field(offset())); break;
216 case T_CHAR: st->print(" (" INT16_FORMAT_X_0 ")", obj->char_field(offset())); break;
217 case T_FLOAT: st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset())); break;
218 case T_INT: st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset())); break;
219 case T_SHORT: st->print(" (" INT16_FORMAT_X_0 ")", obj->short_field(offset())); break;
220 case T_BOOLEAN: st->print(" (" INT8_FORMAT_X_0 ")", obj->bool_field(offset())); break;
221 default:
222 ShouldNotReachHere();
223 break;
224 }
225 }
226 }