1 /*
2 * Copyright (c) 2011, 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 #ifndef SHARE_VM_OOPS_FIELDSTREAMS_HPP
26 #define SHARE_VM_OOPS_FIELDSTREAMS_HPP
27
28 #include "oops/instanceKlass.hpp"
29 #include "oops/fieldInfo.hpp"
30
31 // The is the base class for iteration over the fields array
32 // describing the declared fields in the class. Several subclasses
33 // are provided depending on the kind of iteration required. The
34 // JavaFieldStream is for iterating over regular Java fields and it
35 // generally the preferred iterator. InternalFieldStream only
36 // iterates over fields that have been injected by the JVM.
37 // AllFieldStream exposes all fields and should only be used in rare
38 // cases.
39 class FieldStreamBase : public StackObj {
40 protected:
41 typeArrayHandle _fields;
42 constantPoolHandle _constants;
43 int _index;
44 int _limit;
45
46 FieldInfo* field() const { return FieldInfo::from_field_array(_fields(), _index); }
47
48 FieldStreamBase(typeArrayHandle fields, constantPoolHandle constants, int start, int limit) {
49 _fields = fields;
50 _constants = constants;
51 _index = start;
52 _limit = limit;
53 }
54
55 FieldStreamBase(typeArrayHandle fields, constantPoolHandle constants) {
56 _fields = fields;
57 _constants = constants;
58 _index = 0;
59 _limit = fields->length() / FieldInfo::field_slots;
60 }
61
62 public:
63 FieldStreamBase(instanceKlass* klass) {
64 _fields = klass->fields();
65 _constants = klass->constants();
66 _index = 0;
67 _limit = klass->java_fields_count();
68 }
69 FieldStreamBase(instanceKlassHandle klass) {
70 _fields = klass->fields();
71 _constants = klass->constants();
72 _index = 0;
73 _limit = klass->java_fields_count();
74 }
75
76 // accessors
77 int index() const { return _index; }
78
79 void next() { _index += 1; }
80 bool done() const { return _index >= _limit; }
81
82 // Accessors for current field
83 AccessFlags access_flags() const {
84 AccessFlags flags;
85 flags.set_flags(field()->access_flags());
86 return flags;
87 }
88
89 void set_access_flags(u2 flags) const {
90 field()->set_access_flags(flags);
91 }
92
93 void set_access_flags(AccessFlags flags) const {
94 set_access_flags(flags.as_short());
95 }
96
97 Symbol* name() const {
98 return field()->name(_constants);
99 }
100
101 Symbol* signature() const {
102 return field()->signature(_constants);
103 }
104
105 Symbol* generic_signature() const {
106 return field()->generic_signature(_constants);
107 }
108
109 int offset() const {
110 return field()->offset();
111 }
112
113 void set_offset(int offset) {
114 field()->set_offset(offset);
115 }
116 };
117
118 // Iterate over only the internal fields
119 class JavaFieldStream : public FieldStreamBase {
120 public:
121 JavaFieldStream(instanceKlass* k): FieldStreamBase(k->fields(), k->constants(), 0, k->java_fields_count()) {}
122 JavaFieldStream(instanceKlassHandle k): FieldStreamBase(k->fields(), k->constants(), 0, k->java_fields_count()) {}
123
124 int name_index() const {
125 assert(!field()->is_internal(), "regular only");
126 return field()->name_index();
127 }
128 void set_name_index(int index) {
129 assert(!field()->is_internal(), "regular only");
130 field()->set_name_index(index);
131 }
132 int signature_index() const {
133 assert(!field()->is_internal(), "regular only");
134 return field()->signature_index();
135 }
136 void set_signature_index(int index) {
137 assert(!field()->is_internal(), "regular only");
138 field()->set_signature_index(index);
139 }
140 int generic_signature_index() const {
141 assert(!field()->is_internal(), "regular only");
142 return field()->generic_signature_index();
143 }
144 void set_generic_signature_index(int index) {
145 assert(!field()->is_internal(), "regular only");
146 field()->set_generic_signature_index(index);
147 }
148 int initval_index() const {
149 assert(!field()->is_internal(), "regular only");
150 return field()->initval_index();
151 }
152 void set_initval_index(int index) {
153 assert(!field()->is_internal(), "regular only");
154 return field()->set_initval_index(index);
155 }
156 };
157
158
159 // Iterate over only the internal fields
160 class InternalFieldStream : public FieldStreamBase {
161 public:
162 InternalFieldStream(instanceKlass* k): FieldStreamBase(k->fields(), k->constants(), k->java_fields_count(), k->all_fields_count()) {}
163 InternalFieldStream(instanceKlassHandle k): FieldStreamBase(k->fields(), k->constants(), k->java_fields_count(), k->all_fields_count()) {}
164 };
165
166
167 class AllFieldStream : public FieldStreamBase {
168 public:
169 AllFieldStream(typeArrayHandle fields, constantPoolHandle constants): FieldStreamBase(fields, constants) {}
170 AllFieldStream(instanceKlass* k): FieldStreamBase(k->fields(), k->constants()) {}
171 AllFieldStream(instanceKlassHandle k): FieldStreamBase(k->fields(), k->constants()) {}
172 };
173
174 #endif // SHARE_VM_OOPS_FIELDSTREAMS_HPP