connectivity/source/drivers/hsqldb/HView.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
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   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
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  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
  21 #include <hsqldb/HView.hxx>
  22 #include <hsqldb/HTools.hxx>
  23
  24 #include <propertyids.hxx>
  25
  26 #include <connectivity/dbtools.hxx>
  27
  28 #include <com/sun/star/lang/WrappedTargetException.hpp>
  29 #include <com/sun/star/lang/DisposedException.hpp>
  30 #include <com/sun/star/sdbc/XRow.hpp>
  31 #include <com/sun/star/sdbc/SQLException.hpp>
  32
  33 #include <cppuhelper/exc_hlp.hxx>
  34 #include <tools/diagnose_ex.h>
  35 #include <unotools/sharedunocomponent.hxx>
  36
  37
  38 namespace connectivity::hsqldb
  39 {
  40
  41
  42     using ::com::sun::star::uno::Reference;
  43     using ::com::sun::star::uno::UNO_QUERY_THROW;
  44     using ::com::sun::star::uno::Exception;
  45     using ::com::sun::star::uno::RuntimeException;
  46     using ::com::sun::star::uno::Any;
  47     using ::com::sun::star::sdbc::SQLException;
  48     using ::com::sun::star::sdbc::XConnection;
  49     using ::com::sun::star::lang::WrappedTargetException;
  50     using ::com::sun::star::sdbc::XResultSet;
  51     using ::com::sun::star::sdbc::XStatement;
  52     using ::com::sun::star::lang::DisposedException;
  53     using ::com::sun::star::sdbc::XRow;
  54
  55     HView::HView( const Reference< XConnection >& _rxConnection, bool _bCaseSensitive,
  56         const OUString& _rSchemaName, const OUString& _rName )
  57         :HView_Base( _bCaseSensitive, _rName, _rxConnection->getMetaData(), OUString(), _rSchemaName, OUString() )
  58         ,m_xConnection( _rxConnection )
  59     {
  60     }
  61
  62
  63     HView::~HView()
  64     {
  65     }
  66
  67
  68     IMPLEMENT_FORWARD_XINTERFACE2( HView, HView_Base, HView_IBASE )
  69     IMPLEMENT_FORWARD_XTYPEPROVIDER2( HView, HView_Base, HView_IBASE )
  70
  71
  72     void SAL_CALL HView::alterCommand( const OUString& _rNewCommand )
  73     {
  74         // not really atomic ... as long as we do not have something like
  75         //   ALTER VIEW <name> TO <command>
  76         // in HSQL, we need to do it this way ...
  77         //
  78         // I can imagine scenarios where this fails, e.g. when dropping the view
  79         // succeeds, re-creating it fails, some other thread alters a table which
  80         // the view was based on, and then we try to restore the view with the
  81         // original command, which then fails, too.
  82         //
  83         // However, there's not much chance to prevent this kind of errors without
  84         // backend support.
  85
  86         OUString sQualifiedName( ::dbtools::composeTableName(
  87             m_xMetaData, m_CatalogName, m_SchemaName, m_Name, true, ::dbtools::EComposeRule::InDataManipulation ) );
  88
  89         ::utl::SharedUNOComponent< XStatement > xStatement; xStatement.set( m_xConnection->createStatement(), UNO_QUERY_THROW );
  90
  91         // create a statement which can be used to re-create the original view, in case
  92         // dropping it succeeds, but creating it with a new statement fails
  93         OUString sRestoreCommand =
  94             "CREATE VIEW " +
  95             sQualifiedName +
  96             " AS " +
  97             impl_getCommand_throwSQLException();
  98
  99         bool bDropSucceeded( false );
 100         try
 101         {
 102             // drop the existing view
 103             OUString aCommand  ="DROP VIEW " + sQualifiedName;
 104             xStatement->execute( aCommand );
 105             bDropSucceeded = true;
 106
 107             // create a new one with the same name
 108             aCommand = "CREATE VIEW " + sQualifiedName + " AS " + _rNewCommand;
 109             xStatement->execute( aCommand );
 110         }
 111         catch( const SQLException& )
 112         {
 113             if ( bDropSucceeded )
 114                 // drop succeeded, but creation failed -> re-create the view with the original
 115                 // statement
 116                 xStatement->execute( sRestoreCommand );
 117             throw;
 118         }
 119         catch( const RuntimeException& )
 120         {
 121             if ( bDropSucceeded )
 122                 xStatement->execute( sRestoreCommand );
 123             throw;
 124         }
 125         catch( const Exception& )
 126         {
 127             DBG_UNHANDLED_EXCEPTION("connectivity.hsqldb");
 128             if ( bDropSucceeded )
 129                 xStatement->execute( sRestoreCommand );
 130         }
 131     }
 132
 133
 134     void SAL_CALL HView::getFastPropertyValue( Any& _rValue, sal_Int32 _nHandle ) const
 135     {
 136         if ( _nHandle == PROPERTY_ID_COMMAND )
 137         {
 138             // retrieve the very current command, don't rely on the base classes cached value
 139             // (which we initialized empty, anyway)
 140             _rValue <<= impl_getCommand_wrapSQLException();
 141             return;
 142         }
 143
 144         HView_Base::getFastPropertyValue( _rValue, _nHandle );
 145     }
 146
 147     OUString HView::impl_getCommand() const
 148     {
 149         OUStringBuffer aCommand;
 150         aCommand.append( "SELECT VIEW_DEFINITION FROM INFORMATION_SCHEMA.SYSTEM_VIEWS " );
 151         HTools::appendTableFilterCrit( aCommand, m_CatalogName, m_SchemaName, m_Name, false );
 152         ::utl::SharedUNOComponent< XStatement > xStatement; xStatement.set( m_xConnection->createStatement(), UNO_QUERY_THROW );
 153         Reference< XResultSet > xResult( xStatement->executeQuery( aCommand.makeStringAndClear() ), css::uno::UNO_SET_THROW );
 154         if ( !xResult->next() )
 155         {
 156             // hmm. There is no view the name as we know it. Can only mean some other instance
 157             // dropped this view meanwhile...
 158             throw DisposedException();
 159         }
 160
 161         Reference< XRow > xRow( xResult, UNO_QUERY_THROW );
 162         return xRow->getString( 1 );
 163     }
 164
 165     OUString HView::impl_getCommand_wrapSQLException() const
 166     {
 167         OUString sCommand;
 168
 169         try
 170         {
 171             sCommand = impl_getCommand();
 172         }
 173         catch( const RuntimeException& )
 174         {
 175             throw;
 176         }
 177         catch( const SQLException& e )
 178         {
 179             throw WrappedTargetException( e.Message, static_cast< XAlterView* >( const_cast< HView* >( this ) ), ::cppu::getCaughtException() );
 180         }
 181         catch( const Exception& )
 182         {
 183             DBG_UNHANDLED_EXCEPTION("connectivity.hsqldb");
 184         }
 185
 186         return sCommand;
 187     }
 188
 189     OUString HView::impl_getCommand_throwSQLException() const
 190     {
 191         OUString sCommand;
 192
 193         try
 194         {
 195             sCommand = impl_getCommand();
 196         }
 197         catch( const RuntimeException& )
 198         {
 199             throw;
 200         }
 201         catch( const SQLException& )
 202         {
 203             throw;
 204         }
 205         catch( const Exception& )
 206         {
 207             DBG_UNHANDLED_EXCEPTION("connectivity.hsqldb");
 208         }
 209
 210         return sCommand;
 211     }
 212
 213 } // namespace connectivity::hsqldb
 214
 215
 216 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */