Bug 139343 [regression]Can not use __document to preview report document when deploy birt.
Summary: [regression]Can not use __document to preview report document when deploy birt. Steps to reproduce: 1. Deploy birt 2. Render a report document 3. Preview the report document by using __document Result: The design file C:\apps\jakarta-tomcat-5.5.7\webapps\birt060428\ has error and can not be run.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/context/BaseAttributeBean.java
{
			IScalarParameterDefn parameterObj = (IScalarParameterDefn) iter
					.next( );
			String paramName = parameterObj.getName( );
			Object paramValueObj = this.getParamValueObject( request,
					parameterObj );
			if ( paramValueObj == null )
				paramValueObj = getReportService( ).getParameterDefaultValue(
						design, parameterObj.getName( ), options );
			params.put( paramName, paramValueObj );
		}
		return params;
	}
	protected Object getParamValueObject( HttpServletRequest request,
			IScalarParameterDefn parameterObj ) throws ReportServiceException
	{
		String paramName = parameterObj.getName( );
		String format = parameterObj.getDisplayFormat( );
		if ( ParameterAccessor.isReportParameterExist( request, paramName ) )
		{
			ReportParameterConverter converter = new ReportParameterConverter(
					format, locale );
			
			String paramValue = ParameterAccessor.getReportParameter( request,
					paramName, null );
			return converter.parse( paramValue, parameterObj.getDataType( ) );
		}
		return null;
	}
}