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
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
|
/*************************************************************************
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* Copyright 2000, 2010 Oracle and/or its affiliates.
*
* OpenOffice.org - a multi-platform office productivity suite
*
* This file is part of OpenOffice.org.
*
* OpenOffice.org is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 3
* only, as published by the Free Software Foundation.
*
* OpenOffice.org is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License version 3 for more details
* (a copy is included in the LICENSE file that accompanied this code).
*
* You should have received a copy of the GNU Lesser General Public License
* version 3 along with OpenOffice.org. If not, see
* <http://www.openoffice.org/license.html>
* for a copy of the LGPLv3 License.
*
************************************************************************/
#ifndef _COMPHELPER_OPTIONALVALUE_HXX
#define _COMPHELPER_OPTIONALVALUE_HXX
#include <com/sun/star/uno/Any.hxx>
namespace comphelper
{
/** @deprecated
Use boost/optional.hpp instead.
*/
/* Definition of OptionalValue template */
/** This template provides 'optionality' for the given value type.
Especially for PODs, optionality either needs to be achieved
by special 'magic' values (i.e. an int value is not set when
-1 etc.), or an additional bool denoting value
validity. This template encapsulates the latter into an atomic
data type.
@tpl Element
The value type that should be made optional
*/
template< typename Element > class OptionalValue
{
public:
typedef Element ValueType;
/** Default-construct the value.
A default-constructed value is not valid. You have to
explicitely set a value.
*/
OptionalValue() :
maValue(),
mbValid( false )
{
}
/** Construct the value.
An explicitely constructed value is valid. To create an
invalid value, you have to default-construct it.
*/
OptionalValue( const Element& rValue ) :
maValue( rValue ),
mbValid( true )
{
}
// default copy/assignment operators are okay here
//OptionalValue(const OptionalValue&);
//OptionalValue& operator=( const OptionalValue& );
/** Query whether the value is valid
@return true, if this object contains a valid value.
*/
bool isValid() const
{
return mbValid;
}
/** Set a value.
After this call, the object contains a valid value.
*/
void setValue( const Element& rValue )
{
maValue = rValue;
mbValid = true;
}
/** Get the value.
The return value of this method is undefined, if the
object does not contain a valid value.
*/
Element getValue() const
{
return maValue;
}
/** Clear the value.
After this call, the object no longer contains a valid
value.
*/
void clearValue()
{
mbValid = false;
}
// NOTE: The following two methods would optimally have been
// implemented as operator>>=/operator<<=
// overloads. Unfortunately, there's already a templatized
// version for those two methods, namely for UNO interface
// types. Adding a second would lead to ambiguities.
/** Export the value into an Any.
This method extracts the value into an Any. If the value
is invalid, the Any will be cleared.
@return true, if the value has been successfully
transferred to the Any. Clearing the Any from an invalid
object is also considered a successful operation.
*/
bool exportValue( ::com::sun::star::uno::Any& o_rAny )
{
o_rAny.clear();
if( isValid() )
{
if( !(o_rAny <<= getValue()) )
return false;
}
return true;
}
/** Import the value from an Any.
This method imports the value from an Any. If the Any
is invalid, the object will get an invalid value.
@return true, if the value has been successfully
transferred from the Any. Setting the value to invalid
from an empty Any is also considered a successful
operation.
*/
bool importValue( const ::com::sun::star::uno::Any& rAny )
{
clearValue();
if( rAny.hasValue() )
{
Element tmp;
if( !(rAny >>= tmp) )
return false;
setValue( tmp );
}
return true;
}
private:
Element maValue;
bool mbValid;
};
}
#endif /* _COMPHELPER_OPTIONALVALUE_HXX */
|
