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
return null;
		if ( value instanceof Float || value instanceof Double
				|| value instanceof BigDecimal
				|| value instanceof com.ibm.icu.math.BigDecimal )
		{
			return value.toString( );
		}
		return ParameterValidationUtil.getDisplayValue( value );
	}
	/**
	 * Try convert an object to given type Types supported:
	 * <p>
	 * <ul>
	 * <li>IScalarParameterDefn.TYPE_INTEGER</li>
	 * <li>IScalarParameterDefn.TYPE_DECIMAL</li>
	 * <li>IScalarParameterDefn.TYPE_BOOLEAN</li>
	 * <li>IScalarParameterDefn.TYPE_DATE_TIME</li>
	 * <li>IScalarParameterDefn.TYPE_FLOAT</li>
	 * <li>IScalarParameterDefn.TYPE_STRING</li>
	 * <li>IScalarParameterDefn.TYPE_DATE</li>
	 * <li>IScalarParameterDefn.TYPE_TIME</li>
	 * <ul>
	 * </p>
	 * 
	 * @param source
	 * @param toType
	 * @return
	 * @throws BirtException
	 */
	public static Object convert( Object source, int toType )