1 /*
2 * Copyright (c) 1999, 2010, 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_RUNTIME_REFLECTIONUTILS_HPP
26 #define SHARE_VM_RUNTIME_REFLECTIONUTILS_HPP
27
28 #include "memory/allocation.hpp"
29 #include "oops/instanceKlass.hpp"
30 #include "oops/objArrayOop.hpp"
31 #include "oops/oopsHierarchy.hpp"
32 #include "runtime/handles.inline.hpp"
33 #include "runtime/reflection.hpp"
34 #include "utilities/accessFlags.hpp"
35 #include "utilities/globalDefinitions.hpp"
36
37 // A KlassStream is an abstract stream for streaming over self, superclasses
38 // and (super)interfaces. Streaming is done in reverse order (subclasses first,
39 // interfaces last).
40 //
41 // for (KlassStream st(k, false, false); !st.eos(); st.next()) {
42 // klassOop k = st.klass();
43 // ...
44 // }
45
46 class KlassStream VALUE_OBJ_CLASS_SPEC {
47 protected:
48 instanceKlassHandle _klass; // current klass/interface iterated over
49 objArrayHandle _interfaces; // transitive interfaces for initial class
50 int _interface_index; // current interface being processed
51 bool _local_only; // process initial class/interface only
52 bool _classes_only; // process classes only (no interfaces)
53 int _index;
54
55 virtual int length() const = 0;
56
57 public:
58 // constructor
59 KlassStream(instanceKlassHandle klass, bool local_only, bool classes_only);
60
61 // testing
62 bool eos();
63
64 // iterating
65 virtual void next() = 0;
66
67 // accessors
68 instanceKlassHandle klass() const { return _klass; }
69 int index() const { return _index; }
70 };
71
72
73 // A MethodStream streams over all methods in a class, superclasses and (super)interfaces.
74 // Streaming is done in reverse order (subclasses first, methods in reverse order)
75 // Usage:
76 //
77 // for (MethodStream st(k, false, false); !st.eos(); st.next()) {
78 // methodOop m = st.method();
79 // ...
80 // }
81
82 class MethodStream : public KlassStream {
83 private:
84 int length() const { return methods()->length(); }
85 objArrayOop methods() const { return _klass->methods(); }
86 public:
87 MethodStream(instanceKlassHandle klass, bool local_only, bool classes_only)
88 : KlassStream(klass, local_only, classes_only) {
89 _index = length();
90 next();
91 }
92
93 void next() { _index--; }
94 methodOop method() const { return methodOop(methods()->obj_at(index())); }
95 };
96
97
98 // A FieldStream streams over all fields in a class, superclasses and (super)interfaces.
99 // Streaming is done in reverse order (subclasses first, fields in reverse order)
100 // Usage:
101 //
102 // for (FieldStream st(k, false, false); !st.eos(); st.next()) {
103 // symbolOop field_name = st.name();
104 // ...
105 // }
106
107
108 class FieldStream : public KlassStream {
109 private:
110 int length() const { return fields()->length(); }
111 constantPoolOop constants() const { return _klass->constants(); }
112 protected:
113 typeArrayOop fields() const { return _klass->fields(); }
114 public:
115 FieldStream(instanceKlassHandle klass, bool local_only, bool classes_only)
116 : KlassStream(klass, local_only, classes_only) {
117 _index = length();
118 next();
119 }
120
121 void next() { _index -= instanceKlass::next_offset; }
122
123 // Accessors for current field
124 AccessFlags access_flags() const {
125 AccessFlags flags;
126 flags.set_flags(fields()->ushort_at(index() + instanceKlass::access_flags_offset));
127 return flags;
128 }
129 symbolOop name() const {
130 int name_index = fields()->ushort_at(index() + instanceKlass::name_index_offset);
131 return constants()->symbol_at(name_index);
132 }
133 symbolOop signature() const {
134 int signature_index = fields()->ushort_at(index() +
135 instanceKlass::signature_index_offset);
136 return constants()->symbol_at(signature_index);
137 }
138 // missing: initval()
139 int offset() const {
140 return _klass->offset_from_fields( index() );
141 }
142 };
143
144 class FilteredField {
145 private:
146 klassOop _klass;
147 int _field_offset;
148
149 public:
150 FilteredField(klassOop klass, int field_offset) {
151 _klass = klass;
152 _field_offset = field_offset;
153 }
154 klassOop klass() { return _klass; }
155 oop* klass_addr() { return (oop*) &_klass; }
156 int field_offset() { return _field_offset; }
157 };
158
159 class FilteredFieldsMap : AllStatic {
160 private:
161 static GrowableArray<FilteredField *> *_filtered_fields;
162 public:
163 static void initialize();
164 static bool is_filtered_field(klassOop klass, int field_offset) {
165 for (int i=0; i < _filtered_fields->length(); i++) {
166 if (klass == _filtered_fields->at(i)->klass() &&
167 field_offset == _filtered_fields->at(i)->field_offset()) {
168 return true;
169 }
170 }
171 return false;
172 }
173 static int filtered_fields_count(klassOop klass, bool local_only) {
174 int nflds = 0;
175 for (int i=0; i < _filtered_fields->length(); i++) {
176 if (local_only && klass == _filtered_fields->at(i)->klass()) {
177 nflds++;
178 } else if (klass->klass_part()->is_subtype_of(_filtered_fields->at(i)->klass())) {
179 nflds++;
180 }
181 }
182 return nflds;
183 }
184 // GC support.
185 static void klasses_oops_do(OopClosure* f) {
186 for (int i = 0; i < _filtered_fields->length(); i++) {
187 f->do_oop((oop*)_filtered_fields->at(i)->klass_addr());
188 }
189 }
190 };
191
192
193 // A FilteredFieldStream streams over all fields in a class, superclasses and
194 // (super)interfaces. Streaming is done in reverse order (subclasses first,
195 // fields in reverse order)
196 //
197 // Usage:
198 //
199 // for (FilteredFieldStream st(k, false, false); !st.eos(); st.next()) {
200 // symbolOop field_name = st.name();
201 // ...
202 // }
203
204 class FilteredFieldStream : public FieldStream {
205 private:
206 int _filtered_fields_count;
207 bool has_filtered_field() { return (_filtered_fields_count > 0); }
208
209 public:
210 FilteredFieldStream(instanceKlassHandle klass, bool local_only, bool classes_only)
211 : FieldStream(klass, local_only, classes_only) {
212 _filtered_fields_count = FilteredFieldsMap::filtered_fields_count((klassOop)klass(), local_only);
213 }
214 int field_count();
215 void next() {
216 _index -= instanceKlass::next_offset;
217 if (has_filtered_field()) {
218 while (_index >=0 && FilteredFieldsMap::is_filtered_field((klassOop)_klass(), offset())) {
219 _index -= instanceKlass::next_offset;
220 }
221 }
222 }
223 };
224
225 #endif // SHARE_VM_RUNTIME_REFLECTIONUTILS_HPP