Bug 207250 Check blank value for datetime type parameter from url.[0002][0705]
Description: Check blank value for datetime type parameter from url. Build number:2.3.0.v20071023 Steps to reproduce: 1. New a datetime parameter mydt,listbox, tick off isRequired. 2. Preview in external browser and add "&dt=" in url, press enter. Expected result: Error message to indicate blank value isn't allowed for this parameter. Actual result: No error message and blank value is accepted. I tried to new a jsp and use <birt:paramDef> to pass the blank value and the blank value is accepted,too. Error log:n/a
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/context/ViewerAttributeBean.java
*            HttpServletRequest
	 * @param options
	 *            InputOptions
	 * 
	 * @return Map
	 */
	protected Map getParsedParametersAsStringWithDefaultValue(
			Map parsedParameters, Collection parameterList,
			HttpServletRequest request, InputOptions options )
			throws ReportServiceException
	{
		if ( parsedParameters == null )
			parsedParameters = new HashMap( );
		for ( Iterator iter = parameterList.iterator( ); iter.hasNext( ); )
		{
			
			ParameterDefinition parameter = (ParameterDefinition) iter.next( );
			if ( parameter == null )
				continue;
			
			String paramName = parameter.getName( );
			if ( paramName == null )
				continue;
			
			if ( !parsedParameters.containsKey( paramName ) )
			{
				String paramValue = DataUtil
						.getDisplayValue( this.defaultValues.get( paramName ) );
				if ( parameter.isMultiValue( ) )
				{