connectivity/source/commontools/conncleanup.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
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   5  * This Source Code Form is subject to the terms of the Mozilla Public
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   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
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  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <connectivity/conncleanup.hxx>
  21 #include <com/sun/star/beans/XPropertySet.hpp>
  22 #include <com/sun/star/lang/XComponent.hpp>
  23 #include <com/sun/star/sdbc/XRowSet.hpp>
  24 #include <com/sun/star/sdbc/XConnection.hpp>
  25 #include <osl/diagnose.h>
  26 #include <tools/diagnose_ex.h>
  27
  28
  29 namespace dbtools
  30 {
  31
  32
  33     using namespace css::uno;
  34     using namespace css::beans;
  35     using namespace css::sdbc;
  36     using namespace css::lang;
  37
  38     const char ACTIVE_CONNECTION_PROPERTY_NAME[] = "ActiveConnection";
  39
  40     OAutoConnectionDisposer::OAutoConnectionDisposer(const Reference< XRowSet >& _rxRowSet, const Reference< XConnection >& _rxConnection)
  41         :m_xRowSet( _rxRowSet )
  42         ,m_bRSListening( false )
  43         ,m_bPropertyListening( false )
  44     {
  45         Reference< XPropertySet > xProps(_rxRowSet, UNO_QUERY);
  46         OSL_ENSURE(xProps.is(), "OAutoConnectionDisposer::OAutoConnectionDisposer: invalid rowset (no XPropertySet)!");
  47
  48         if (!xProps.is())
  49             return;
  50
  51         try
  52         {
  53             xProps->setPropertyValue( ACTIVE_CONNECTION_PROPERTY_NAME, makeAny( _rxConnection ) );
  54             m_xOriginalConnection = _rxConnection;
  55             startPropertyListening( xProps );
  56         }
  57         catch( const Exception& )
  58         {
  59             TOOLS_WARN_EXCEPTION( "connectivity.commontools", "OAutoConnectionDisposer::OAutoConnectionDisposer" );
  60         }
  61     }
  62
  63
  64     void OAutoConnectionDisposer::startPropertyListening( const Reference< XPropertySet >& _rxRowSet )
  65     {
  66         try
  67         {
  68             _rxRowSet->addPropertyChangeListener( ACTIVE_CONNECTION_PROPERTY_NAME, this );
  69             m_bPropertyListening = true;
  70         }
  71         catch( const Exception& )
  72         {
  73             TOOLS_WARN_EXCEPTION( "connectivity.commontools", "OAutoConnectionDisposer::startPropertyListening" );
  74         }
  75     }
  76
  77
  78     void OAutoConnectionDisposer::stopPropertyListening( const Reference< XPropertySet >& _rxEventSource )
  79     {
  80         // prevent deletion of ourself while we're herein
  81         Reference< XInterface > xKeepAlive(static_cast< XWeak* >(this));
  82
  83         try
  84         {   // remove ourself as property change listener
  85             OSL_ENSURE( _rxEventSource.is(), "OAutoConnectionDisposer::stopPropertyListening: invalid event source (no XPropertySet)!" );
  86             if ( _rxEventSource.is() )
  87             {
  88                 _rxEventSource->removePropertyChangeListener( ACTIVE_CONNECTION_PROPERTY_NAME, this );
  89                 m_bPropertyListening = false;
  90             }
  91         }
  92         catch( const Exception& )
  93         {
  94             TOOLS_WARN_EXCEPTION( "connectivity.commontools", "OAutoConnectionDisposer::stopPropertyListening" );
  95         }
  96     }
  97
  98
  99     void OAutoConnectionDisposer::startRowSetListening()
 100     {
 101         OSL_ENSURE( !m_bRSListening, "OAutoConnectionDisposer::startRowSetListening: already listening!" );
 102         try
 103         {
 104             if ( !m_bRSListening )
 105                 m_xRowSet->addRowSetListener( this );
 106         }
 107         catch( const Exception& )
 108         {
 109             TOOLS_WARN_EXCEPTION( "connectivity.commontools", "OAutoConnectionDisposer::startRowSetListening" );
 110         }
 111         m_bRSListening = true;
 112     }
 113
 114
 115     void OAutoConnectionDisposer::stopRowSetListening()
 116     {
 117         OSL_ENSURE( m_bRSListening, "OAutoConnectionDisposer::stopRowSetListening: not listening!" );
 118         try
 119         {
 120             m_xRowSet->removeRowSetListener( this );
 121         }
 122         catch( const Exception& )
 123         {
 124             TOOLS_WARN_EXCEPTION( "connectivity.commontools", "OAutoConnectionDisposer::stopRowSetListening" );
 125         }
 126         m_bRSListening = false;
 127     }
 128
 129
 130     void SAL_CALL OAutoConnectionDisposer::propertyChange( const PropertyChangeEvent& _rEvent )
 131     {
 132         if ( _rEvent.PropertyName != ACTIVE_CONNECTION_PROPERTY_NAME )
 133             return;
 134
 135 // somebody set a new ActiveConnection
 136
 137         Reference< XConnection > xNewConnection;
 138         _rEvent.NewValue >>= xNewConnection;
 139
 140         if ( isRowSetListening() )
 141         {
 142             // we're listening at the row set, this means that the row set does not have our
 143             // m_xOriginalConnection as active connection anymore
 144             // So there are two possibilities
 145             // a. somebody sets a new connection which is not our original one
 146             // b. somebody sets a new connection, which is exactly the original one
 147             // a. we're not interested in a, but in b: In this case, we simply need to move to the state
 148             // we had originally: listen for property changes, do not listen for row set changes, and
 149             // do not dispose the connection until the row set does not need it anymore
 150             if ( xNewConnection.get() == m_xOriginalConnection.get() )
 151             {
 152                 stopRowSetListening();
 153             }
 154         }
 155         else
 156         {
 157             // start listening at the row set. We're allowed to dispose the old connection as soon
 158             // as the RowSet changed
 159
 160             // Unfortunately, the our database form implementations sometimes fire the change of their
 161             // ActiveConnection twice. This is an error in forms/source/component/DatabaseForm.cxx, but
 162             // changing this would require incompatible changes we can't do for a while.
 163             // So for the moment, we have to live with it here.
 164             //
 165             // The only scenario where this doubled notification causes problems is when the connection
 166             // of the form is reset to the one we're responsible for (m_xOriginalConnection), so we
 167             // check this here.
 168             //
 169             // Yes, this is a HACK :(
 170             if ( xNewConnection.get() != m_xOriginalConnection.get() )
 171             {
 172 #if OSL_DEBUG_LEVEL > 0
 173                 Reference< XConnection > xOldConnection;
 174                 _rEvent.OldValue >>= xOldConnection;
 175                 OSL_ENSURE( xOldConnection.get() == m_xOriginalConnection.get(), "OAutoConnectionDisposer::propertyChange: unexpected (original) property value!" );
 176 #endif
 177                 startRowSetListening();
 178             }
 179         }
 180     }
 181
 182
 183     void SAL_CALL OAutoConnectionDisposer::disposing( const EventObject& _rSource )
 184     {
 185         // the rowset is being disposed, and nobody has set a new ActiveConnection in the meantime
 186         if ( isRowSetListening() )
 187             stopRowSetListening();
 188
 189         clearConnection();
 190
 191         if ( m_bPropertyListening )
 192             stopPropertyListening( Reference< XPropertySet >( _rSource.Source, UNO_QUERY ) );
 193     }
 194
 195     void OAutoConnectionDisposer::clearConnection()
 196     {
 197         try
 198         {
 199             // dispose the old connection
 200             Reference< XComponent > xComp(m_xOriginalConnection, UNO_QUERY);
 201             if (xComp.is())
 202                 xComp->dispose();
 203             m_xOriginalConnection.clear();
 204         }
 205         catch(Exception&)
 206         {
 207             TOOLS_WARN_EXCEPTION("connectivity.commontools", "OAutoConnectionDisposer::clearConnection");
 208         }
 209     }
 210
 211     void SAL_CALL OAutoConnectionDisposer::cursorMoved( const css::lang::EventObject& /*event*/ )
 212     {
 213     }
 214
 215     void SAL_CALL OAutoConnectionDisposer::rowChanged( const css::lang::EventObject& /*event*/ )
 216     {
 217     }
 218
 219     void SAL_CALL OAutoConnectionDisposer::rowSetChanged( const css::lang::EventObject& /*event*/ )
 220     {
 221         stopRowSetListening();
 222         clearConnection();
 223
 224     }
 225
 226
 227 }   // namespace dbtools
 228
 229
 230 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */