code: public static Class<?> getPropertyTypeOptional(
          Class<?> beanClass, String propertyName)
      {
          PropertyDescriptor propertyDescriptor =
              getPropertyDescriptorOptional(beanClass, propertyName);
          if (propertyDescriptor == null)
          {
              return null;
          }
          return propertyDescriptor.getPropertyType();
      }
docs: Returns the type of the property with the given name in the given
  bean class. Returns <code>null</code> if there is no such property,
  or the property is an indexed property that does not allow non-indexed
  access.
  
  @param beanClass The bean class
  @param propertyName The property name
  @return The type of the property, or <code>null</code> if there
  is no such property.