Bug 141951 Export data throw NPE when target document doesn't exist
Description: Export data doesn't work when deploy birt in WebSphere6 Steps to reproduce: 1. Deploy birt in WebSphere6 2. Preview report and click Export Data Result: java.lang.NullPointerException Stack Trace: org.apache.axis.AxisFault.makeFault(AxisFault.java:101) org.eclipse.birt.report.soapengine.processor.AbstractBaseComponentProcessor.process(Unknown Source) org.eclipse.birt.report.soapengine.endpoint.BirtSoapBindingImpl.getUpdatedObjects(Unknown Source) sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) sun.reflect.NativeMethodAccessorImpl
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/service/BirtViewerReportService.java
Collection columns, Set filters, InputOptions options,
			OutputStream out ) throws ReportServiceException
	{
		IReportDocument doc = ReportEngineService.getInstance( )
				.openReportDocument( getReportDesignName( options ), docName );
		Locale locale = (Locale) options.getOption( InputOptions.OPT_LOCALE );
		
		try
		{
			ReportEngineService.getInstance( ).extractData( doc, resultSetId,
					columns, locale, out );
			doc.close( );
		}
		catch ( RemoteException e )
		{
			throw new ReportServiceException( e.getLocalizedMessage( ) );
		}
	}
	public List getResultSetsMetadata( String docName, InputOptions options )
			throws ReportServiceException
	{
		IReportDocument doc = ReportEngineService.getInstance( )
				.openReportDocument( getReportDesignName( options ), docName );
		ResultSet[] resultSetArray;
		try
		{
			resultSetArray = ReportEngineService.getInstance( ).getResultSets(
					doc );
			doc.close( );
		}