Bug 180608 [Regression]NPE throws out when preview the result in dataset[07]
Description: [Regression]NPE throws out when preview the result in dataset[07] Build number: 2.2.0.v20070403-0630 Steps to reproduce: 1, Use attached report 2, Edit Data Set 3, Preview the Data Set Expected result: The preview should be success Actual result: NPE throws out Error log:
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/executor/ResultClass.java
int writeCount = 0;
			for ( int i = 0; i < m_fieldCount; i++ )
			{
				ResultFieldMetadata column = projectedCols[i];
				
				
				if (resultSetNameSet.remove(column.getName())
						|| resultSetNameSet.remove(column.getAlias()))
				{
					IOUtil.writeInt( dos, column.getDriverPosition( ) );
					IOUtil.writeString( dos, column.getName( ) );
					IOUtil.writeString( dos, column.getLabel( ) );
					IOUtil.writeString( dos, column.getAlias( ) );
					IOUtil.writeString( dos, column.getDataType( ).getName( ) );
					IOUtil.writeString( dos, column.getNativeTypeName( ) );
					IOUtil.writeBool( dos, column.isCustom( ) );
					if ( column.getDriverProvidedDataType( ) == null )
						IOUtil.writeString( dos, null );
					else
						IOUtil.writeString( dos,
								column.getDriverProvidedDataType( ).getName( ) );
					writeCount++;
				}
			}
			
			if ( writeCount != size)
			{
				StringBuffer buf = new StringBuffer( );
				for ( Iterator i = resultSetNameSet.iterator( ); i.hasNext( ); )
				{