1/*
2 * Copyright (c) 1999, 2019, 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_RUNTIME_REFLECTIONUTILS_HPP
26#define SHARE_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.hpp"
33#include "runtime/reflection.hpp"
34#include "utilities/accessFlags.hpp"
35#include "utilities/globalDefinitions.hpp"
36#include "utilities/growableArray.hpp"
37
38// A KlassStream is an abstract stream for streaming over self, superclasses
39// and (super)interfaces. Streaming is done in reverse order (subclasses first,
40// interfaces last).
41//
42// for (KlassStream st(k, false, false, false); !st.eos(); st.next()) {
43// Klass* k = st.klass();
44// ...
45// }
46
47class KlassStream {
48 protected:
49 InstanceKlass* _klass; // current klass/interface iterated over
50 InstanceKlass* _base_klass; // initial klass/interface to iterate over
51 Array<InstanceKlass*>*_interfaces; // transitive interfaces for initial class
52 int _interface_index; // current interface being processed
53 bool _local_only; // process initial class/interface only
54 bool _classes_only; // process classes only (no interfaces)
55 bool _walk_defaults; // process default methods
56 bool _base_class_search_defaults; // time to process default methods
57 bool _defaults_checked; // already checked for default methods
58 int _index;
59
60 virtual int length() = 0;
61
62 public:
63 // constructor
64 KlassStream(InstanceKlass* klass, bool local_only, bool classes_only, bool walk_defaults);
65
66 // testing
67 bool eos();
68
69 // iterating
70 virtual void next() = 0;
71
72 // accessors
73 InstanceKlass* klass() const { return _klass; }
74 int index() const { return _index; }
75 bool base_class_search_defaults() const { return _base_class_search_defaults; }
76 void base_class_search_defaults(bool b) { _base_class_search_defaults = b; }
77};
78
79
80// A MethodStream streams over all methods in a class, superclasses and (super)interfaces.
81// Streaming is done in reverse order (subclasses first, methods in reverse order)
82// Usage:
83//
84// for (MethodStream st(k, false, false); !st.eos(); st.next()) {
85// Method* m = st.method();
86// ...
87// }
88
89class MethodStream : public KlassStream {
90 private:
91 int length() { return methods()->length(); }
92 Array<Method*>* methods() {
93 if (base_class_search_defaults()) {
94 base_class_search_defaults(false);
95 return _klass->default_methods();
96 } else {
97 return _klass->methods();
98 }
99 }
100 public:
101 MethodStream(InstanceKlass* klass, bool local_only, bool classes_only)
102 : KlassStream(klass, local_only, classes_only, true) {
103 _index = length();
104 next();
105 }
106
107 void next() { _index--; }
108 Method* method() { return methods()->at(index()); }
109};
110
111
112// A FieldStream streams over all fields in a class, superclasses and (super)interfaces.
113// Streaming is done in reverse order (subclasses first, fields in reverse order)
114// Usage:
115//
116// for (FieldStream st(k, false, false); !st.eos(); st.next()) {
117// Symbol* field_name = st.name();
118// ...
119// }
120
121
122class FieldStream : public KlassStream {
123 private:
124 int length() { return _klass->java_fields_count(); }
125
126 fieldDescriptor _fd_buf;
127
128 public:
129 FieldStream(InstanceKlass* klass, bool local_only, bool classes_only)
130 : KlassStream(klass, local_only, classes_only, false) {
131 _index = length();
132 next();
133 }
134
135 void next() { _index -= 1; }
136
137 // Accessors for current field
138 AccessFlags access_flags() const {
139 AccessFlags flags;
140 flags.set_flags(_klass->field_access_flags(_index));
141 return flags;
142 }
143 Symbol* name() const {
144 return _klass->field_name(_index);
145 }
146 Symbol* signature() const {
147 return _klass->field_signature(_index);
148 }
149 // missing: initval()
150 int offset() const {
151 return _klass->field_offset( index() );
152 }
153 // bridge to a heavier API:
154 fieldDescriptor& field_descriptor() const {
155 fieldDescriptor& field = const_cast<fieldDescriptor&>(_fd_buf);
156 field.reinitialize(_klass, _index);
157 return field;
158 }
159};
160
161class FilteredField : public CHeapObj<mtInternal> {
162 private:
163 Klass* _klass;
164 int _field_offset;
165
166 public:
167 FilteredField(Klass* klass, int field_offset) {
168 _klass = klass;
169 _field_offset = field_offset;
170 }
171 Klass* klass() { return _klass; }
172 int field_offset() { return _field_offset; }
173};
174
175class FilteredFieldsMap : AllStatic {
176 private:
177 static GrowableArray<FilteredField *> *_filtered_fields;
178 public:
179 static void initialize();
180 static bool is_filtered_field(Klass* klass, int field_offset) {
181 for (int i=0; i < _filtered_fields->length(); i++) {
182 if (klass == _filtered_fields->at(i)->klass() &&
183 field_offset == _filtered_fields->at(i)->field_offset()) {
184 return true;
185 }
186 }
187 return false;
188 }
189 static int filtered_fields_count(Klass* klass, bool local_only) {
190 int nflds = 0;
191 for (int i=0; i < _filtered_fields->length(); i++) {
192 if (local_only && klass == _filtered_fields->at(i)->klass()) {
193 nflds++;
194 } else if (klass->is_subtype_of(_filtered_fields->at(i)->klass())) {
195 nflds++;
196 }
197 }
198 return nflds;
199 }
200};
201
202
203// A FilteredFieldStream streams over all fields in a class, superclasses and
204// (super)interfaces. Streaming is done in reverse order (subclasses first,
205// fields in reverse order)
206//
207// Usage:
208//
209// for (FilteredFieldStream st(k, false, false); !st.eos(); st.next()) {
210// Symbol* field_name = st.name();
211// ...
212// }
213
214class FilteredFieldStream : public FieldStream {
215 private:
216 int _filtered_fields_count;
217 bool has_filtered_field() { return (_filtered_fields_count > 0); }
218
219 public:
220 FilteredFieldStream(InstanceKlass* klass, bool local_only, bool classes_only)
221 : FieldStream(klass, local_only, classes_only) {
222 _filtered_fields_count = FilteredFieldsMap::filtered_fields_count(klass, local_only);
223 }
224 int field_count();
225 void next() {
226 _index -= 1;
227 if (has_filtered_field()) {
228 while (_index >=0 && FilteredFieldsMap::is_filtered_field((Klass*)_klass, offset())) {
229 _index -= 1;
230 }
231 }
232 }
233};
234
235#endif // SHARE_RUNTIME_REFLECTIONUTILS_HPP
236