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.
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_on(outputStream* st) const {
112 access_flags().print_on(st);
113 if (field_flags().is_injected()) st->print("injected ");
114 name()->print_value_on(st);
115 st->print(" ");
116 signature()->print_value_on(st);
117 st->print(" @%d ", offset());
118 if (WizardMode && has_initial_value()) {
119 st->print("(initval ");
120 constantTag t = initial_value_tag();
121 if (t.is_int()) {
122 st->print("int %d)", int_initial_value());
123 } else if (t.is_long()){
124 st->print_jlong(long_initial_value());
125 } else if (t.is_float()){
126 st->print("float %f)", float_initial_value());
127 } else if (t.is_double()){
128 st->print("double %lf)", double_initial_value());
129 }
130 }
131 }
132
133 void fieldDescriptor::print() const { print_on(tty); }
134
135 void fieldDescriptor::print_on_for(outputStream* st, oop obj) {
136 print_on(st);
137 st->print(" ");
138
139 BasicType ft = field_type();
140 switch (ft) {
141 case T_BYTE:
142 st->print("%d", obj->byte_field(offset()));
143 break;
144 case T_CHAR:
145 {
146 jchar c = obj->char_field(offset());
147 st->print("%c %d", isprint(c) ? c : ' ', c);
148 }
149 break;
150 case T_DOUBLE:
151 st->print("%lf", obj->double_field(offset()));
152 break;
153 case T_FLOAT:
154 st->print("%f", obj->float_field(offset()));
155 break;
156 case T_INT:
157 st->print("%d", obj->int_field(offset()));
158 break;
159 case T_LONG:
160 st->print_jlong(obj->long_field(offset()));
161 break;
162 case T_SHORT:
163 st->print("%d", obj->short_field(offset()));
164 break;
165 case T_BOOLEAN:
166 st->print("%s", obj->bool_field(offset()) ? "true" : "false");
167 break;
168 case T_ARRAY:
169 if (obj->obj_field(offset()) != nullptr) {
170 obj->obj_field(offset())->print_value_on(st);
171 } else {
172 st->print("null");
173 }
174 break;
175 case T_OBJECT:
176 if (obj->obj_field(offset()) != nullptr) {
177 obj->obj_field(offset())->print_value_on(st);
178 } else {
179 st->print("null");
180 }
181 break;
182 default:
183 ShouldNotReachHere();
184 break;
185 }
186
187 // Print a hint as to the underlying integer representation.
188 if (is_reference_type(ft)) {
189 #ifdef _LP64
190 if (UseCompressedOops) {
191 st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset()));
192 } else {
193 st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset()));
194 }
195 #else
196 st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset()));
197 #endif
198 } else { // Primitives
199 switch (ft) {
200 case T_LONG: st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset())); break;
201 case T_DOUBLE: st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset())); break;
202 case T_BYTE: st->print(" (" INT8_FORMAT_X_0 ")", obj->byte_field(offset())); break;
203 case T_CHAR: st->print(" (" INT16_FORMAT_X_0 ")", obj->char_field(offset())); break;
204 case T_FLOAT: st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset())); break;
205 case T_INT: st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset())); break;
206 case T_SHORT: st->print(" (" INT16_FORMAT_X_0 ")", obj->short_field(offset())); break;
207 case T_BOOLEAN: st->print(" (" INT8_FORMAT_X_0 ")", obj->bool_field(offset())); break;
208 default:
209 ShouldNotReachHere();
210 break;
211 }
212 }
213 }