Bug 201030 NPE throws out when preview the attached report design
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/script/ScriptEvalUtil.java
}
	/**
	 * Most objects should already be formatted to the same type by method
	 * formatToComparable at this point if neither of them is null. This method
	 * will therefore be terminated pretty soon except for calling from method
	 * between with weird parameters like obj:String, op1:Double and op2:Date.
	 * 
	 * @param obj1
	 * @param obj2
	 * @return -1,0 and 1 standing for <,= and > respectively
	 * @throws DataException
	 */
	public static int compare( Object obj1, Object obj2 ) throws DataException
	{
	    if (obj1 == null || obj2 == null) 
	    {
            
	        if (obj1 == null && obj2 != null)
                return -1;
            else if (obj1 != null && obj2 == null)
                return 1;
            else
                return 0;
        }
	    
		try
		{
			if ( MiscUtil.isSameType( obj1, obj2 ) )
			{
				if ( obj1 instanceof Boolean )