include/unotools/configvaluecontainer.hxx

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