object_registry.h revision fc0e3219edc9a5bf81b166e82fd5db2796eb6a0d 
1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ART_RUNTIME_JDWP_OBJECT_REGISTRY_H_
18#define ART_RUNTIME_JDWP_OBJECT_REGISTRY_H_
19
20#include <stdint.h>
21
22#include <map>
23
24#include "jdwp/jdwp.h"
25#include "mirror/class.h"
26#include "mirror/class-inl.h"
27#include "mirror/field-inl.h"
28#include "mirror/object-inl.h"
29#include "safe_map.h"
30
31namespace art {
32
33struct ObjectRegistryEntry {
34  // Is jni_reference a weak global or a regular global reference?
35  jobjectRefType jni_reference_type;
36
37  // The reference itself.
38  jobject jni_reference;
39
40  // A reference count, so we can implement DisposeObject.
41  int32_t reference_count;
42
43  // The corresponding id, so we only need one map lookup in Add.
44  JDWP::ObjectId id;
45};
46std::ostream& operator<<(std::ostream& os, const ObjectRegistryEntry& rhs);
47
48// Tracks those objects currently known to the debugger, so we can use consistent ids when
49// referring to them. Normally we keep JNI weak global references to objects, so they can
50// still be garbage collected. The debugger can ask us to retain objects, though, so we can
51// also promote references to regular JNI global references (and demote them back again if
52// the debugger tells us that's okay).
53class ObjectRegistry {
54 public:
55  ObjectRegistry();
56
57  JDWP::ObjectId Add(mirror::Object* o) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
58  JDWP::RefTypeId AddRefType(mirror::Class* c) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
59
60  template<typename T> T Get(JDWP::ObjectId id) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
61    if (id == 0) {
62      return NULL;
63    }
64    return reinterpret_cast<T>(InternalGet(id));
65  }
66
67  bool Contains(mirror::Object* o) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
68
69  void Clear() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
70
71  void DisableCollection(JDWP::ObjectId id) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
72  void EnableCollection(JDWP::ObjectId id) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
73
74  bool IsCollected(JDWP::ObjectId id) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
75
76  void DisposeObject(JDWP::ObjectId id, uint32_t reference_count)
77      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
78
79  // Returned by Get when passed an invalid object id.
80  static mirror::Object* const kInvalidObject;
81
82  // This is needed to get the jobject instead of the Object*.
83  // Avoid using this and use standard Get when possible.
84  jobject GetJObject(JDWP::ObjectId id) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
85
86 private:
87  JDWP::ObjectId InternalAdd(mirror::Object* o) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
88  mirror::Object* InternalGet(JDWP::ObjectId id) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
89  void Demote(ObjectRegistryEntry& entry) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, lock_);
90  void Promote(ObjectRegistryEntry& entry) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, lock_);
91
92  Mutex lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
93
94  typedef std::map<mirror::Object*, ObjectRegistryEntry>::iterator object_iterator;
95  std::map<mirror::Object*, ObjectRegistryEntry> object_to_entry_ GUARDED_BY(lock_);
96
97  typedef SafeMap<JDWP::ObjectId, ObjectRegistryEntry*>::iterator id_iterator;
98  SafeMap<JDWP::ObjectId, ObjectRegistryEntry*> id_to_entry_ GUARDED_BY(lock_);
99
100  size_t next_id_ GUARDED_BY(lock_);
101};
102
103}  // namespace art
104
105#endif  // ART_RUNTIME_JDWP_OBJECT_REGISTRY_H_
106