1 /*
2 * Copyright (c) 1999, 2013, 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 // Klass* k = st.klass();
43 // ...
44 // }
45
46 class KlassStream VALUE_OBJ_CLASS_SPEC {
47 protected:
48 instanceKlassHandle _klass; // current klass/interface iterated over
49 Array<Klass*>* _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 // Method* m = st.method();
79 // ...
80 // }
81
82 class MethodStream : public KlassStream {
83 private:
84 int length() const { return methods()->length(); }
85 Array<Method*>* 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 Method* method() const { return methods()->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 // Symbol* field_name = st.name();
104 // ...
105 // }
106
107
108 class FieldStream : public KlassStream {
109 private:
110 int length() const { return _klass->java_fields_count(); }
111
112 fieldDescriptor _fd_buf;
113
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 -= 1; }
122
123 // Accessors for current field
124 AccessFlags access_flags() const {
125 AccessFlags flags;
126 flags.set_flags(_klass->field_access_flags(_index));
127 return flags;
128 }
129 Symbol* name() const {
130 return _klass->field_name(_index);
131 }
132 Symbol* signature() const {
133 return _klass->field_signature(_index);
134 }
135 // missing: initval()
136 int offset() const {
137 return _klass->field_offset( index() );
138 }
139 // bridge to a heavier API:
140 fieldDescriptor& field_descriptor() const {
141 fieldDescriptor& field = const_cast<fieldDescriptor&>(_fd_buf);
142 field.reinitialize(_klass(), _index);
143 return field;
144 }
145 };
146
147 class FilteredField : public CHeapObj<mtInternal> {
148 private:
149 Klass* _klass;
150 int _field_offset;
151
152 public:
153 FilteredField(Klass* klass, int field_offset) {
154 _klass = klass;
155 _field_offset = field_offset;
156 }
157 Klass* klass() { return _klass; }
158 int field_offset() { return _field_offset; }
159 };
160
161 class FilteredFieldsMap : AllStatic {
162 private:
163 static GrowableArray<FilteredField *> *_filtered_fields;
164 public:
165 static void initialize();
166 static bool is_filtered_field(Klass* klass, int field_offset) {
167 for (int i=0; i < _filtered_fields->length(); i++) {
168 if (klass == _filtered_fields->at(i)->klass() &&
169 field_offset == _filtered_fields->at(i)->field_offset()) {
170 return true;
171 }
172 }
173 return false;
174 }
175 static int filtered_fields_count(Klass* klass, bool local_only) {
176 int nflds = 0;
177 for (int i=0; i < _filtered_fields->length(); i++) {
178 if (local_only && klass == _filtered_fields->at(i)->klass()) {
179 nflds++;
180 } else if (klass->is_subtype_of(_filtered_fields->at(i)->klass())) {
181 nflds++;
182 }
183 }
184 return nflds;
185 }
186 // Enhance Class Redefinition Support
187 static void classes_do(KlassClosure* f) {
188 for (int i = 0; i < _filtered_fields->length(); i++) {
189 f->do_klass(_filtered_fields->at(i)->klass());
190 }
191 }
192 };
193
194
195 // A FilteredFieldStream streams over all fields in a class, superclasses and
196 // (super)interfaces. Streaming is done in reverse order (subclasses first,
197 // fields in reverse order)
198 //
199 // Usage:
200 //
201 // for (FilteredFieldStream st(k, false, false); !st.eos(); st.next()) {
202 // Symbol* field_name = st.name();
203 // ...
204 // }
205
206 class FilteredFieldStream : public FieldStream {
207 private:
208 int _filtered_fields_count;
209 bool has_filtered_field() { return (_filtered_fields_count > 0); }
210
211 public:
212 FilteredFieldStream(instanceKlassHandle klass, bool local_only, bool classes_only)
213 : FieldStream(klass, local_only, classes_only) {
214 _filtered_fields_count = FilteredFieldsMap::filtered_fields_count((Klass*)klass(), local_only);
215 }
216 int field_count();
217 void next() {
218 _index -= 1;
219 if (has_filtered_field()) {
220 while (_index >=0 && FilteredFieldsMap::is_filtered_field((Klass*)_klass(), offset())) {
221 _index -= 1;
222 }
223 }
224 }
225 };
226
227 #endif // SHARE_VM_RUNTIME_REFLECTIONUTILS_HPP