include/unotools/configvaluecontainer.hxx

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  19 #ifndef INCLUDED_UNOTOOLS_CONFIGVALUECONTAINER_HXX
  20 #define INCLUDED_UNOTOOLS_CONFIGVALUECONTAINER_HXX
  21
  22 #include <config_options.h>
  23 #include <unotools/unotoolsdllapi.h>
  24 #include <com/sun/star/uno/Type.hxx>
  25 #include <memory>
  26
  27
  28 namespace com::sun::star::uno { template <typename > class Reference; }
  29 namespace com::sun::star::uno { class XComponentContext; }
  30 namespace osl { class Mutex; }
  31
  32 namespace utl
  33 {
  34
  35     struct OConfigurationValueContainerImpl;
  36     struct NodeValueAccessor;
  37
  38     //= OConfigurationValueContainer
  39
  40     /** allows simple access to static configuration structures.
  41
  42         <p>The basic idea of this class is that it's clients (usually derived classes) simply register an
  43         address in memory and a node path, and upon explicit request, the configuration value and the memory
  44         are synchronized.<br/>
  45         This means that when calling <method>read</method>, the current configuration values are copied into
  46         the memory registered for them, and upon calling <method>write</method> the current values in memory
  47         are set in the configuration nodes.</p>
  48
  49         <p>This way, the usage of this class is pretty straight forward: derive your own class, spend some members
  50         to it, and bind these members to configuration node (usually done in the ctor of the derived class).<br/>
  51         In the dtor, simply call <method>write</method> and <method>commit</method>.</p>
  52
  53         <p>There is no auto-commit mechanism in the dtor: In the usual scenario, when you derive from this class
  54         and bind some members of your derived class to config nodes, this means that your members will be destroyed
  55         before your base class' dtor is called, so accessing the memory during such a theoretical auto-commit would
  56         yield undefined behaviour.</p>
  57     */
  58     class UNLESS_MERGELIBS(UNOTOOLS_DLLPUBLIC) OConfigurationValueContainer
  59     {
  60     private:
  61         std::unique_ptr<OConfigurationValueContainerImpl> m_pImpl;
  62
  63     protected:
  64
  65         // construction/destruction
  66
  67         /** constructs the object
  68
  69             @param _rxORB
  70                 specifies the service factory which should be used to access the configuration
  71             @param _rAccessSafety
  72                 As this class is intended to manipulate objects it does not hold itself (see the various
  73                 registerXXX methods), it needs to guard these access for multi threading safety.<br/>
  74                 The mutex given here is locked whenever such an access occurs.
  75             @param _pConfigLocation
  76                 is an ASCII string describing the configurations node path
  77             @param _nAccessFlags
  78                 specifies different aspects of the configuration aspect to be created, e.g. it's update mode etc.<br/>
  79                 See the CVC_xxx constants for what you can use here.
  80             @param _nLevels
  81                 specifies the number of levels to access under the node given by <arg>_pConfigLocation</arg>
  82         */
  83         OConfigurationValueContainer(
  84             const css::uno::Reference< css::uno::XComponentContext >& _rxORB,
  85             ::osl::Mutex& _rAccessSafety,
  86             const char* _pConfigLocation,
  87             const sal_Int32 _nLevels
  88         );
  89
  90         /// dtor
  91         ~OConfigurationValueContainer();
  92
  93         // registering data containers
  94
  95         /** registers a data accessor of an arbitrary type.
  96
  97             <p>Usually, in your derived class you simply add a member of the correct type of the configuration
  98             value, and then call this method with the address of this member.</p>
  99
 100             @param _pRelativePathAscii
 101                 is a relative (ASCII) path of the node which should be "mirrored" into the accessor.
 102             @param _pContainer
 103                 points to the accessors location in memory. Usually, this is simply an address of your derived class
 104             @param _rValueType
 105                 is the type of your accessor. This type must be supported by the configuration.
 106         */
 107         void    registerExchangeLocation(
 108             const char* _pRelativePathAscii,
 109             void* _pContainer,
 110             const css::uno::Type& _rValueType
 111         );
 112
 113     public:
 114         /** reads the configuration data
 115
 116             <p>The current values of the nodes bound (using the registerXXX methods) is copied into their
 117             respective exchange locations.</p>
 118
 119             <p>Please note that any changes done to your exchange locations are overridden with the current config
 120             values.</p>
 121
 122             @see write
 123         */
 124         void    read( );
 125
 126         /** commits any changes done
 127
 128             <p>Note that calling <method>write</method>(<sal_True/) is the same as calling <method>commit</method>(<TRUE/>).</p>
 129
 130             The current values in the exchange locations are written to the configuration nodes
 131             before the changes are committed.<br/>
 132
 133             @precond
 134                 The access must have been created for update access
 135         */
 136         void    commit();
 137
 138     private:
 139         /// implements the ctors
 140         void implConstruct(
 141             const OUString& _rConfigLocation,
 142             const sal_Int32 _nLevels
 143         );
 144
 145         /// registers a value container
 146         void    implRegisterExchangeLocation( const NodeValueAccessor& _rAccessor );
 147     };
 148
 149 }   // namespace utl
 150
 151 #endif // INCLUDED_UNOTOOLS_CONFIGVALUECONTAINER_HXX
 152
 153 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */