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/utility/DataUtil.java
{
		Object obj = null;
		if ( value == null )
			return obj;
		try
		{
			if ( format == null )
			{
				if ( DesignChoiceConstants.PARAM_TYPE_DATE
						.equalsIgnoreCase( dataType ) )
				{
					format = ParameterValidationUtil.DISPLAY_DATE_FORMAT;
				}
				else if ( DesignChoiceConstants.PARAM_TYPE_TIME
						.equalsIgnoreCase( dataType ) )
				{
					format = ParameterValidationUtil.DISPLAY_TIME_FORMAT;
				}
				else if ( DesignChoiceConstants.PARAM_TYPE_DATETIME
						.equalsIgnoreCase( dataType ) )
				{
					format = DesignChoiceConstants.DATETIEM_FORMAT_TYPE_UNFORMATTED;
				}
			}
			
			obj = ParameterValidationUtil.validate( dataType, format, value,
					locale );
		}
		catch ( Exception e )
		{