jdk

Форк
0
/
jvmtiGetLoadedClasses.cpp 
143 строки · 5.1 Кб
1
/*
2
 * Copyright (c) 2003, 2024, 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
#include "precompiled.hpp"
26
#include "classfile/classLoaderDataGraph.hpp"
27
#include "classfile/dictionary.hpp"
28
#include "classfile/javaClasses.hpp"
29
#include "gc/shared/collectedHeap.hpp"
30
#include "memory/universe.hpp"
31
#include "oops/klass.inline.hpp"
32
#include "prims/jvmtiGetLoadedClasses.hpp"
33
#include "runtime/handles.inline.hpp"
34
#include "runtime/javaThread.hpp"
35
#include "runtime/jniHandles.inline.hpp"
36
#include "utilities/stack.inline.hpp"
37

38
// The closure for GetLoadedClasses
39
class LoadedClassesClosure : public KlassClosure {
40
private:
41
  Stack<jclass, mtInternal> _classStack;
42
  JvmtiEnv* _env;
43
  Thread*   _cur_thread;
44
  bool      _dictionary_walk;
45

46
  int extract(jclass* result_list) {
47
    // The size of the Stack will be 0 after extract, so get it here
48
    int count = (int)_classStack.size();
49
    int i = count;
50

51
    // Pop all jclasses, fill backwards
52
    while (!_classStack.is_empty()) {
53
      result_list[--i] = _classStack.pop();
54
    }
55

56
    // Return the number of elements written
57
    return count;
58
  }
59

60
  // Return current size of the Stack
61
  int get_count() {
62
    return (int)_classStack.size();
63
  }
64

65
public:
66
  LoadedClassesClosure(JvmtiEnv* env, bool dictionary_walk) :
67
      _env(env),
68
      _cur_thread(Thread::current()),
69
      _dictionary_walk(dictionary_walk) {
70
  }
71

72
  void do_klass(Klass* k) {
73
    // Collect all jclasses
74
    _classStack.push((jclass) _env->jni_reference(Handle(_cur_thread, k->java_mirror())));
75
    if (_dictionary_walk) {
76
      // Collect array classes this way when walking the dictionary (because array classes are
77
      // not in the dictionary).
78
      for (Klass* l = k->array_klass_or_null(); l != nullptr; l = l->array_klass_or_null()) {
79
        _classStack.push((jclass) _env->jni_reference(Handle(_cur_thread, l->java_mirror())));
80
      }
81
    }
82
  }
83

84
  jvmtiError get_result(JvmtiEnv *env, jint* classCountPtr, jclass** classesPtr) {
85
    // Return results by extracting the collected contents into a list
86
    // allocated via JvmtiEnv
87
    jclass* result_list;
88
    jvmtiError error = env->Allocate(get_count() * sizeof(jclass),
89
                               (unsigned char**)&result_list);
90

91
    if (error == JVMTI_ERROR_NONE) {
92
      int count = extract(result_list);
93
      *classCountPtr = count;
94
      *classesPtr = result_list;
95
    }
96
    return error;
97
  }
98
};
99

100
jvmtiError
101
JvmtiGetLoadedClasses::getLoadedClasses(JvmtiEnv *env, jint* classCountPtr, jclass** classesPtr) {
102

103
  LoadedClassesClosure closure(env, false);
104
  {
105
    // Iterate through all classes in ClassLoaderDataGraph
106
    // and collect them using the LoadedClassesClosure
107
    MutexLocker mcld(ClassLoaderDataGraph_lock);
108
    ClassLoaderDataGraph::loaded_classes_do_keepalive(&closure);
109
  }
110

111
  return closure.get_result(env, classCountPtr, classesPtr);
112
}
113

114
jvmtiError
115
JvmtiGetLoadedClasses::getClassLoaderClasses(JvmtiEnv *env, jobject initiatingLoader,
116
                                             jint* classCountPtr, jclass** classesPtr) {
117

118
  LoadedClassesClosure closure(env, true);
119
  {
120
    // To get a consistent list of classes we need MultiArray_lock to ensure
121
    // array classes aren't created by another thread during this walk. This walks through the
122
    // InstanceKlass::_array_klasses links.
123
    RecursiveLocker ma(MultiArray_lock, Thread::current());
124
    MutexLocker sd(SystemDictionary_lock);
125
    oop loader = JNIHandles::resolve(initiatingLoader);
126
    // All classes loaded from this loader as initiating loader are
127
    // requested, so only need to walk this loader's ClassLoaderData
128
    // dictionary, or the null ClassLoaderData dictionary for bootstrap loader.
129
    if (loader != nullptr) {
130
      ClassLoaderData* data = java_lang_ClassLoader::loader_data_acquire(loader);
131
      // ClassLoader may not be used yet for loading.
132
      if (data != nullptr && data->dictionary() != nullptr) {
133
        data->dictionary()->all_entries_do(&closure);
134
      }
135
    } else {
136
      ClassLoaderData::the_null_class_loader_data()->dictionary()->all_entries_do(&closure);
137
    }
138
    // Get basic arrays for all loaders.
139
    Universe::basic_type_classes_do(&closure);
140
  }
141

142
  return closure.get_result(env, classCountPtr, classesPtr);
143
}
144

Использование cookies

Мы используем файлы cookie в соответствии с Политикой конфиденциальности и Политикой использования cookies.

Нажимая кнопку «Принимаю», Вы даете АО «СберТех» согласие на обработку Ваших персональных данных в целях совершенствования нашего веб-сайта и Сервиса GitVerse, а также повышения удобства их использования.

Запретить использование cookies Вы можете самостоятельно в настройках Вашего браузера.