code: public static boolean canFormat(ConfigurablePropertyAccessor bw,
  			Object obj, String prop) {
  		String key = obj.getClass().getName() + "_" + prop;
  
  		if (!cache.containsKey(key)) {
  			cache.put(key, false);
  
  			TypeDescriptor td = bw.getPropertyTypeDescriptor(prop);
  			if (td != null) {
  				WinletDefaultFormattingConversionService wcs = get();
  				if (wcs != null
  						&& wcs.hasFmtAnnotation(td)
  						&& wcs.canConvert(td,
  								TypeDescriptor.valueOf(String.class)))
  					cache.put(key, true);
  			}
  		}
  
  		return cache.get(key);
  	}
docs: 判断对象属性是否有格式可以应用。调用format()前必须先调用canFormat()
  
  @param obj
  @param prop
  @return