conncleanup.cxx

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#include <connectivity/conncleanup.hxx>
#include <com/sun/star/beans/XPropertySet.hpp>
#include <com/sun/star/lang/XComponent.hpp>
#include <com/sun/star/sdbc/XRowSet.hpp>
#include <com/sun/star/sdbc/XConnection.hpp>
#include <osl/diagnose.h>
#include <comphelper/diagnose_ex.hxx>
 
 
namespace dbtools
{
 
 
    using namespace css::uno;
    using namespace css::beans;
    using namespace css::sdbc;
    using namespace css::lang;
 
    constexpr OUStringLiteral ACTIVE_CONNECTION_PROPERTY_NAME = u"ActiveConnection";
 
    OAutoConnectionDisposer::OAutoConnectionDisposer(const Reference< XRowSet >& _rxRowSet, const Reference< XConnection >& _rxConnection)
        :m_xRowSet( _rxRowSet )
        ,m_bRSListening( false )
        ,m_bPropertyListening( false )
    {
        Reference< XPropertySet > xProps(_rxRowSet, UNO_QUERY);
        OSL_ENSURE(xProps.is(), "OAutoConnectionDisposer::OAutoConnectionDisposer: invalid rowset (no XPropertySet)!");
 
        if (!xProps.is())
            return;
 
        try
        {
            xProps->setPropertyValue( ACTIVE_CONNECTION_PROPERTY_NAME, Any( _rxConnection ) );
            m_xOriginalConnection = _rxConnection;
            startPropertyListening( xProps );
        }
        catch( const Exception& )
        {
            TOOLS_WARN_EXCEPTION( "connectivity.commontools", "OAutoConnectionDisposer::OAutoConnectionDisposer" );
        }
    }
 
 
    void OAutoConnectionDisposer::startPropertyListening( const Reference< XPropertySet >& _rxRowSet )
    {
        try
        {
            _rxRowSet->addPropertyChangeListener( ACTIVE_CONNECTION_PROPERTY_NAME, this );
            m_bPropertyListening = true;
        }
        catch( const Exception& )
        {
            TOOLS_WARN_EXCEPTION( "connectivity.commontools", "OAutoConnectionDisposer::startPropertyListening" );
        }
    }
 
 
    void OAutoConnectionDisposer::stopPropertyListening( const Reference< XPropertySet >& _rxEventSource )
    {
        // prevent deletion of ourself while we're herein
        Reference< XInterface > xKeepAlive(getXWeak());
 
        try
        {   // remove ourself as property change listener
            OSL_ENSURE( _rxEventSource.is(), "OAutoConnectionDisposer::stopPropertyListening: invalid event source (no XPropertySet)!" );
            if ( _rxEventSource.is() )
            {
                _rxEventSource->removePropertyChangeListener( ACTIVE_CONNECTION_PROPERTY_NAME, this );
                m_bPropertyListening = false;
            }
        }
        catch( const Exception& )
        {
            TOOLS_WARN_EXCEPTION( "connectivity.commontools", "OAutoConnectionDisposer::stopPropertyListening" );
        }
    }
 
 
    void OAutoConnectionDisposer::startRowSetListening()
    {
        OSL_ENSURE( !m_bRSListening, "OAutoConnectionDisposer::startRowSetListening: already listening!" );
        try
        {
            if ( !m_bRSListening )
                m_xRowSet->addRowSetListener( this );
        }
        catch( const Exception& )
        {
            TOOLS_WARN_EXCEPTION( "connectivity.commontools", "OAutoConnectionDisposer::startRowSetListening" );
        }
        m_bRSListening = true;
    }
 
 
    void OAutoConnectionDisposer::stopRowSetListening()
    {
        OSL_ENSURE( m_bRSListening, "OAutoConnectionDisposer::stopRowSetListening: not listening!" );
        try
        {
            m_xRowSet->removeRowSetListener( this );
        }
        catch( const Exception& )
        {
            TOOLS_WARN_EXCEPTION( "connectivity.commontools", "OAutoConnectionDisposer::stopRowSetListening" );
        }
        m_bRSListening = false;
    }
 
 
    void SAL_CALL OAutoConnectionDisposer::propertyChange( const PropertyChangeEvent& _rEvent )
    {
        if ( _rEvent.PropertyName != ACTIVE_CONNECTION_PROPERTY_NAME )
            return;
 
// somebody set a new ActiveConnection
 
        Reference< XConnection > xNewConnection;
        _rEvent.NewValue >>= xNewConnection;
 
        if ( isRowSetListening() )
        {
            // we're listening at the row set, this means that the row set does not have our
            // m_xOriginalConnection as active connection anymore
            // So there are two possibilities
            // a. somebody sets a new connection which is not our original one
            // b. somebody sets a new connection, which is exactly the original one
            // a. we're not interested in a, but in b: In this case, we simply need to move to the state
            // we had originally: listen for property changes, do not listen for row set changes, and
            // do not dispose the connection until the row set does not need it anymore
            if ( xNewConnection.get() == m_xOriginalConnection.get() )
            {
                stopRowSetListening();
            }
        }
        else
        {
            // start listening at the row set. We're allowed to dispose the old connection as soon
            // as the RowSet changed
 
            // Unfortunately, the our database form implementations sometimes fire the change of their
            // ActiveConnection twice. This is an error in forms/source/component/DatabaseForm.cxx, but
            // changing this would require incompatible changes we can't do for a while.
            // So for the moment, we have to live with it here.
            //
            // The only scenario where this doubled notification causes problems is when the connection
            // of the form is reset to the one we're responsible for (m_xOriginalConnection), so we
            // check this here.
            //
            // Yes, this is a HACK :(
            if ( xNewConnection.get() != m_xOriginalConnection.get() )
            {
#if OSL_DEBUG_LEVEL > 0
                Reference< XConnection > xOldConnection;
                _rEvent.OldValue >>= xOldConnection;
                OSL_ENSURE( xOldConnection.get() == m_xOriginalConnection.get(), "OAutoConnectionDisposer::propertyChange: unexpected (original) property value!" );
#endif
                startRowSetListening();
            }
        }
    }
 
 
    void SAL_CALL OAutoConnectionDisposer::disposing( const EventObject& _rSource )
    {
        // the rowset is being disposed, and nobody has set a new ActiveConnection in the meantime
        if ( isRowSetListening() )
            stopRowSetListening();
 
        clearConnection();
 
        if ( m_bPropertyListening )
            stopPropertyListening( Reference< XPropertySet >( _rSource.Source, UNO_QUERY ) );
    }
 
    void OAutoConnectionDisposer::clearConnection()
    {
        try
        {
            // dispose the old connection
            Reference< XComponent > xComp(m_xOriginalConnection, UNO_QUERY);
            if (xComp.is())
                xComp->dispose();
            m_xOriginalConnection.clear();
        }
        catch(Exception&)
        {
            TOOLS_WARN_EXCEPTION("connectivity.commontools", "OAutoConnectionDisposer::clearConnection");
        }
    }
 
    void SAL_CALL OAutoConnectionDisposer::cursorMoved( const css::lang::EventObject& /*event*/ )
    {
    }
 
    void SAL_CALL OAutoConnectionDisposer::rowChanged( const css::lang::EventObject& /*event*/ )
    {
    }
 
    void SAL_CALL OAutoConnectionDisposer::rowSetChanged( const css::lang::EventObject& /*event*/ )
    {
        stopRowSetListening();
        clearConnection();
 
    }
 
 
}   // namespace dbtools
 
 
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