1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
|
/* -*- C++ -*- */
// $Id$
// ============================================================================
//
// = LIBRARY
// ace
//
// = FILENAME
// Singleton.h
//
// = DESCRIPTION
//
// = AUTHOR
// Tim Harrison (harrison@cs.wustl.edu), Douglas C. Schmidt, Chris
// Lahey, Rich Christy, and David Levine.
//
// ============================================================================
#if !defined (ACE_SINGLETON_H)
#define ACE_SINGLETON_H
#include "ace/Synch.h"
template <class TYPE, class ACE_LOCK>
class ACE_Singleton : public ACE_Cleanup
// = TITLE
// A Singleton Adapter the uses the Adapter pattern to turn
// ordinary classes into Singletons optimized with the
// Double-Checked Locking optimization pattern.
//
// = DESCRIPTION
// This implementation is a slight variation on the GoF
// Singleton pattern. In particular, a single
// <ACE_Singleton<TYPE, ACE_LOCK> > instance is allocated here, not
// a <TYPE> instance. The reason for this is to allow
// registration with the <ACE_Object_Manager>, so that the
// Singleton can be cleaned up when the process exits. For this
// scheme to work, a (static) <cleanup> function must be
// provided. <ACE_Singleton> provides one so that TYPE doesn't
// need to.
{
public:
static TYPE *instance (void);
// Global access point to the Singleton.
virtual void cleanup (void *param = 0);
// Cleanup method, used by <ace_cleanup_destroyer> to destroy the
// <ACE_Singleton>.
static void dump (void);
// Dump the state of the object.
protected:
ACE_Singleton (void);
// Default constructor.
TYPE instance_;
// Contained instance.
#if !defined (ACE_LACKS_STATIC_DATA_MEMBER_TEMPLATES)
static ACE_Singleton<TYPE, ACE_LOCK> *singleton_;
// Pointer to the Singleton (ACE_Cleanup) instance.
#endif /* ACE_LACKS_STATIC_DATA_MEMBER_TEMPLATES */
static ACE_Singleton<TYPE, ACE_LOCK> *&instance_i (void);
// Get pointer to the Singleton instance.
};
template <class TYPE, class ACE_LOCK>
class ACE_TSS_Singleton : public ACE_Cleanup
// = TITLE
// This class uses the Adapter pattern to turn ordinary classes
// into Thread-specific Singletons optimized with the
// Double-Checked Locking optimization pattern.
//
// = DESCRIPTION
// This implementation is another variation on the GoF Singleton
// pattern. In this case, a single <ACE_TSS_Singleton<TYPE,
// LOCK> > instance is allocated here, not a <TYPE> instance.
// Each call to the <instance> static method returns a Singleton
// whose pointer resides in thread-specific storage. As with
// <ACE_Singleton>, we use the <ACE_Object_Manager> so that the
// Singleton can be cleaned up when the process exits. For this
// scheme to work, a (static) <cleanup> function must be
// provided. <ACE_Singleton> provides one so that TYPE doesn't
// need to.
{
public:
static TYPE *instance (void);
// Global access point to the Singleton.
virtual void cleanup (void *param = 0);
// Cleanup method, used by <ace_cleanup_destroyer> to destroy the
// singleton.
static void dump (void);
// Dump the state of the object.
protected:
ACE_TSS_Singleton (void);
// Default constructor.
ACE_TSS<TYPE> instance_;
// Contained instance.
#if !defined (ACE_LACKS_STATIC_DATA_MEMBER_TEMPLATES)
static ACE_TSS_Singleton<TYPE, ACE_LOCK> *singleton_;
// Pointer to the Singleton (ACE_Cleanup) instance.
#endif /* ACE_LACKS_STATIC_DATA_MEMBER_TEMPLATES */
static ACE_TSS_Singleton<TYPE, ACE_LOCK> *&instance_i (void);
// Get pointer to the TSS Singleton instance.
};
#if defined (__ACE_INLINE__)
#include "ace/Singleton.i"
#endif /* __ACE_INLINE__ */
#if defined (ACE_TEMPLATES_REQUIRE_SOURCE)
#include "ace/Singleton.cpp"
#endif /* ACE_TEMPLATES_REQUIRE_SOURCE */
#if defined (ACE_TEMPLATES_REQUIRE_PRAGMA)
#pragma implementation ("Singleton.cpp")
#endif /* ACE_TEMPLATES_REQUIRE_PRAGMA */
#endif /* ACE_SINGLETON_H */
|
