Bug 147407 Preview the attached report in the web viewer first time and then click the TOC button will cause NPE error
Description: It just can be reprouduced at first time preview. Step to reproduce: 1. please use attach report file 2. preview it in the web viewer 3. click the "Toggle table of contents" button Actual result: As the atteched screenshot shows,There is a NPE error.And if you preview it in the Web viewer again, the phenomenon is disappear.But reopen the eclipse and preview it at first time, it will be occured.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
&& !paramName.equalsIgnoreCase( name ) ) 
				
				
				{
					paramName = urlEncode( paramName, ISO_8859_1_ENCODE );
					queryString += ( isFirst ? "" : PARAMETER_SEPARATOR ) + PARAM_ISNULL + EQUALS_OPERATOR + paramName; 
					isFirst = false;
					continue;
				}
				if ( paramName.equalsIgnoreCase( name ) )
				{
					paramValue = value;
				}
				paramName = urlEncode( paramName, ISO_8859_1_ENCODE );
				paramValue = urlEncode( paramValue, UTF_8_ENCODE );
				queryString += ( isFirst ? "" : PARAMETER_SEPARATOR ) + paramName + EQUALS_OPERATOR + paramValue; 
				isFirst = false;
			}
		}
		if ( nullParams != null && nullParams.size( ) > 0 )
		{
			Iterator i = nullParams.iterator( );
			while ( i.hasNext( ) )
			{
				String paramName = (String) i.next( );
				if ( paramName != null && !paramName.equalsIgnoreCase( name ) )
				{
					paramName = urlEncode( paramName, UTF_8_ENCODE );
					queryString += ( isFirst ? "" : PARAMETER_SEPARATOR ) + PARAM_ISNULL + EQUALS_OPERATOR + paramName;  
					isFirst = false;