classLoadingService.hpp revision 3730:fb19af007ffc 
1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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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.
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24
25#ifndef SHARE_VM_SERVICES_CLASSLOADINGSERVICE_HPP
26#define SHARE_VM_SERVICES_CLASSLOADINGSERVICE_HPP
27
28#include "runtime/handles.hpp"
29#include "runtime/perfData.hpp"
30#include "utilities/growableArray.hpp"
31
32class InstanceKlass;
33
34// VM monitoring and management support for the Class Loading subsystem
35class ClassLoadingService : public AllStatic {
36private:
37  // Counters for classes loaded from class files
38  static PerfCounter*  _classes_loaded_count;
39  static PerfCounter*  _classes_unloaded_count;
40  static PerfCounter*  _classbytes_loaded;
41  static PerfCounter*  _classbytes_unloaded;
42
43  // Counters for classes loaded from shared archive
44  static PerfCounter*  _shared_classes_loaded_count;
45  static PerfCounter*  _shared_classes_unloaded_count;
46  static PerfCounter*  _shared_classbytes_loaded;
47  static PerfCounter*  _shared_classbytes_unloaded;
48
49  static PerfVariable* _class_methods_size;
50
51  static size_t compute_class_size(InstanceKlass* k);
52
53public:
54  static void init();
55
56  static bool get_verbose() { return TraceClassLoading; }
57  static bool set_verbose(bool verbose);
58  static void reset_trace_class_unloading() NOT_MANAGEMENT_RETURN;
59
60  static jlong loaded_class_count() {
61    return _classes_loaded_count->get_value() + _shared_classes_loaded_count->get_value();
62  }
63  static jlong unloaded_class_count() {
64    return _classes_unloaded_count->get_value() + _shared_classes_unloaded_count->get_value();
65  }
66  static jlong loaded_class_bytes() {
67    if (UsePerfData) {
68      return _classbytes_loaded->get_value() + _shared_classbytes_loaded->get_value();
69    } else {
70      return -1;
71    }
72  }
73  static jlong unloaded_class_bytes() {
74    if (UsePerfData) {
75      return _classbytes_unloaded->get_value() + _shared_classbytes_unloaded->get_value();
76    } else {
77      return -1;
78    }
79  }
80
81  static jlong loaded_shared_class_count() {
82    return _shared_classes_loaded_count->get_value();
83  }
84  static jlong unloaded_shared_class_count() {
85    return _shared_classes_unloaded_count->get_value();
86  }
87  static jlong loaded_shared_class_bytes() {
88    if (UsePerfData) {
89      return _shared_classbytes_loaded->get_value();
90    } else {
91      return -1;
92    }
93  }
94  static jlong unloaded_shared_class_bytes() {
95    if (UsePerfData) {
96      return _shared_classbytes_unloaded->get_value();
97    } else {
98      return -1;
99    }
100  }
101  static jlong class_method_data_size() {
102    return (UsePerfData ? _class_methods_size->get_value() : -1);
103  }
104
105  static void notify_class_loaded(InstanceKlass* k, bool shared_class)
106      NOT_MANAGEMENT_RETURN;
107  // All unloaded classes are non-shared
108  static void notify_class_unloaded(InstanceKlass* k) NOT_MANAGEMENT_RETURN;
109  static void add_class_method_size(int size) {
110#if INCLUDE_MANAGEMENT
111    if (UsePerfData) {
112      _class_methods_size->inc(size);
113    }
114#endif // INCLUDE_MANAGEMENT
115  }
116};
117
118// FIXME: make this piece of code to be shared by M&M and JVMTI
119class LoadedClassesEnumerator : public StackObj {
120private:
121  static GrowableArray<KlassHandle>* _loaded_classes;
122  // _current_thread is for creating a KlassHandle with a faster version constructor
123  static Thread*                     _current_thread;
124
125  GrowableArray<KlassHandle>* _klass_handle_array;
126
127public:
128  LoadedClassesEnumerator(Thread* cur_thread);
129
130  int num_loaded_classes()         { return _klass_handle_array->length(); }
131  KlassHandle get_klass(int index) { return _klass_handle_array->at(index); }
132
133  static void add_loaded_class(Klass* k) {
134    // FIXME: For now - don't include array klasses
135    // The spec is unclear at this point to count array klasses or not
136    // and also indirect creation of array of super class and secondaries
137    //
138    // for (Klass* l = k; l != NULL; l = Klass::cast(l)->array_klass_or_null()) {
139    //  KlassHandle h(_current_thread, l);
140    //  _loaded_classes->append(h);
141    // }
142    KlassHandle h(_current_thread, k);
143    _loaded_classes->append(h);
144  }
145};
146
147#endif // SHARE_VM_SERVICES_CLASSLOADINGSERVICE_HPP
148