connectivity/source/commontools/conncleanup.cxx

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  28
  29 #include <connectivity/conncleanup.hxx>
  30 #include <com/sun/star/beans/XPropertySet.hpp>
  31 #include <com/sun/star/lang/XComponent.hpp>
  32 #include <osl/diagnose.h>
  33
  34 //.........................................................................
  35 namespace dbtools
  36 {
  37 //.........................................................................
  38
  39     using namespace ::com::sun::star::uno;
  40     using namespace ::com::sun::star::beans;
  41     using namespace ::com::sun::star::sdbc;
  42     using namespace ::com::sun::star::lang;
  43
  44     //=====================================================================
  45     static const ::rtl::OUString& getActiveConnectionPropertyName()
  46     {
  47         static const ::rtl::OUString s_sActiveConnectionPropertyName( RTL_CONSTASCII_USTRINGPARAM( "ActiveConnection" ));
  48         return s_sActiveConnectionPropertyName;
  49     }
  50
  51     //=====================================================================
  52     //= OAutoConnectionDisposer
  53     //=====================================================================
  54     //---------------------------------------------------------------------
  55     OAutoConnectionDisposer::OAutoConnectionDisposer(const Reference< XRowSet >& _rxRowSet, const Reference< XConnection >& _rxConnection)
  56         :m_xRowSet( _rxRowSet )
  57         ,m_bRSListening( sal_False )
  58         ,m_bPropertyListening( sal_False )
  59     {
  60         Reference< XPropertySet > xProps(_rxRowSet, UNO_QUERY);
  61         OSL_ENSURE(xProps.is(), "OAutoConnectionDisposer::OAutoConnectionDisposer: invalid rowset (no XPropertySet)!");
  62
  63         if (!xProps.is())
  64             return;
  65
  66         try
  67         {
  68             xProps->setPropertyValue( getActiveConnectionPropertyName(), makeAny( _rxConnection ) );
  69             m_xOriginalConnection = _rxConnection;
  70             startPropertyListening( xProps );
  71         }
  72         catch( const Exception& )
  73         {
  74             OSL_FAIL( "OAutoConnectionDisposer::OAutoConnectionDisposer: caught an exception!" );
  75         }
  76     }
  77
  78     //---------------------------------------------------------------------
  79     void OAutoConnectionDisposer::startPropertyListening( const Reference< XPropertySet >& _rxRowSet )
  80     {
  81         try
  82         {
  83             _rxRowSet->addPropertyChangeListener( getActiveConnectionPropertyName(), this );
  84             m_bPropertyListening = sal_True;
  85         }
  86         catch( const Exception& )
  87         {
  88             OSL_FAIL( "OAutoConnectionDisposer::startPropertyListening: caught an exception!" );
  89         }
  90     }
  91
  92     //---------------------------------------------------------------------
  93     void OAutoConnectionDisposer::stopPropertyListening( const Reference< XPropertySet >& _rxEventSource )
  94     {
  95         // prevent deletion of ourself while we're herein
  96         Reference< XInterface > xKeepAlive(static_cast< XWeak* >(this));
  97
  98         try
  99         {   // remove ourself as property change listener
 100             OSL_ENSURE( _rxEventSource.is(), "OAutoConnectionDisposer::stopPropertyListening: invalid event source (no XPropertySet)!" );
 101             if ( _rxEventSource.is() )
 102             {
 103                 _rxEventSource->removePropertyChangeListener( getActiveConnectionPropertyName(), this );
 104                 m_bPropertyListening = sal_False;
 105             }
 106         }
 107         catch( const Exception& )
 108         {
 109             OSL_FAIL( "OAutoConnectionDisposer::stopPropertyListening: caught an exception!" );
 110         }
 111     }
 112
 113     //---------------------------------------------------------------------
 114     void OAutoConnectionDisposer::startRowSetListening()
 115     {
 116         OSL_ENSURE( !m_bRSListening, "OAutoConnectionDisposer::startRowSetListening: already listening!" );
 117         try
 118         {
 119             if ( !m_bRSListening )
 120                 m_xRowSet->addRowSetListener( this );
 121         }
 122         catch( const Exception& )
 123         {
 124             OSL_FAIL( "OAutoConnectionDisposer::startRowSetListening: caught an exception!" );
 125         }
 126         m_bRSListening = sal_True;
 127     }
 128
 129     //---------------------------------------------------------------------
 130     void OAutoConnectionDisposer::stopRowSetListening()
 131     {
 132         OSL_ENSURE( m_bRSListening, "OAutoConnectionDisposer::stopRowSetListening: not listening!" );
 133         try
 134         {
 135             m_xRowSet->removeRowSetListener( this );
 136         }
 137         catch( const Exception& )
 138         {
 139             OSL_FAIL( "OAutoConnectionDisposer::stopRowSetListening: caught an exception!" );
 140         }
 141         m_bRSListening = sal_False;
 142     }
 143
 144     //---------------------------------------------------------------------
 145     void SAL_CALL OAutoConnectionDisposer::propertyChange( const PropertyChangeEvent& _rEvent ) throw (RuntimeException)
 146     {
 147         if ( _rEvent.PropertyName.equals( getActiveConnectionPropertyName() ) )
 148         {   // somebody set a new ActiveConnection
 149
 150             Reference< XConnection > xNewConnection;
 151             _rEvent.NewValue >>= xNewConnection;
 152
 153             if ( isRowSetListening() )
 154             {
 155                 // we're listening at the row set, this means that the row set does not have our
 156                 // m_xOriginalConnection as active connection anymore
 157                 // So there are two possibilities
 158                 // a. somebody sets a new connection which is not our original one
 159                 // b. somebody sets a new connection, which is exactly the original one
 160                 // a. we're not interested in a, but in b: In this case, we simply need to move to the state
 161                 // we had originally: listen for property changes, do not listen for row set changes, and
 162                 // do not dispose the connection until the row set does not need it anymore
 163                 if ( xNewConnection.get() == m_xOriginalConnection.get() )
 164                 {
 165                     stopRowSetListening();
 166                 }
 167             }
 168             else
 169             {
 170                 // start listening at the row set. We're allowed to dispose the old connection as soon
 171                 // as the RowSet changed
 172
 173                 // Unfortunately, the our database form implementations sometimes fire the change of their
 174                 // ActiveConnection twice. This is a error in forms/source/component/DatabaseForm.cxx, but
 175                 // changing this would require incompatible changes we can't do for a while.
 176                 // So for the moment, we have to live with it here.
 177                 //
 178                 // The only scenario where this doubled notification causes problems is when the connection
 179                 // of the form is reset to the one we're responsible for (m_xOriginalConnection), so we
 180                 // check this here.
 181                 //
 182                 // Yes, this is a HACK :(
 183                 if ( xNewConnection.get() != m_xOriginalConnection.get() )
 184                 {
 185 #if OSL_DEBUG_LEVEL > 0
 186                     Reference< XConnection > xOldConnection;
 187                     _rEvent.OldValue >>= xOldConnection;
 188                     OSL_ENSURE( xOldConnection.get() == m_xOriginalConnection.get(), "OAutoConnectionDisposer::propertyChange: unexpected (original) property value!" );
 189 #endif
 190                     startRowSetListening();
 191                 }
 192             }
 193         }
 194     }
 195
 196     //---------------------------------------------------------------------
 197     void SAL_CALL OAutoConnectionDisposer::disposing( const EventObject& _rSource ) throw (RuntimeException)
 198     {
 199         // the rowset is beeing disposed, and nobody has set a new ActiveConnection in the meantime
 200         if ( isRowSetListening() )
 201             stopRowSetListening();
 202
 203         clearConnection();
 204
 205         if ( isPropertyListening() )
 206             stopPropertyListening( Reference< XPropertySet >( _rSource.Source, UNO_QUERY ) );
 207     }
 208     //---------------------------------------------------------------------
 209     void OAutoConnectionDisposer::clearConnection()
 210     {
 211         try
 212         {
 213             // dispose the old connection
 214             Reference< XComponent > xComp(m_xOriginalConnection, UNO_QUERY);
 215             if (xComp.is())
 216                 xComp->dispose();
 217             m_xOriginalConnection.clear();
 218         }
 219         catch(Exception&)
 220         {
 221             OSL_FAIL("OAutoConnectionDisposer::clearConnection: caught an exception!");
 222         }
 223     }
 224     //---------------------------------------------------------------------
 225     void SAL_CALL OAutoConnectionDisposer::cursorMoved( const ::com::sun::star::lang::EventObject& /*event*/ ) throw (::com::sun::star::uno::RuntimeException)
 226     {
 227     }
 228     //---------------------------------------------------------------------
 229     void SAL_CALL OAutoConnectionDisposer::rowChanged( const ::com::sun::star::lang::EventObject& /*event*/ ) throw (::com::sun::star::uno::RuntimeException)
 230     {
 231     }
 232     //---------------------------------------------------------------------
 233     void SAL_CALL OAutoConnectionDisposer::rowSetChanged( const ::com::sun::star::lang::EventObject& /*event*/ ) throw (::com::sun::star::uno::RuntimeException)
 234     {
 235         stopRowSetListening();
 236         clearConnection();
 237
 238     }
 239     //---------------------------------------------------------------------
 240
 241 //.........................................................................
 242 }   // namespace dbtools
 243 //.........................................................................
 244
 245 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */