public interface PriorityOrdered extends Ordered
Ordered interface, expressing a priority
 ordering: PriorityOrdered objects are always applied before
 plain Ordered objects regardless of their order values.
 When sorting a set of Ordered objects, PriorityOrdered
 objects and plain Ordered objects are effectively treated as
 two separate subsets, with the set of PriorityOrdered objects preceding
 the set of plain Ordered objects and with relative
 ordering applied within those subsets.
 
This is primarily a special-purpose interface, used within the framework
 itself for objects where it is particularly important to recognize
 prioritized objects first, potentially without even obtaining the
 remaining objects. A typical example: prioritized post-processors in a Spring
 org.springframework.context.ApplicationContext.
 
Note: PriorityOrdered post-processor beans are initialized in
 a special phase, ahead of other post-processor beans. This subtly
 affects their autowiring behavior: they will only be autowired against
 beans which do not require eager initialization for type matching.
org.springframework.beans.factory.config.PropertyOverrideConfigurer, 
org.springframework.beans.factory.config.PropertyPlaceholderConfigurerHIGHEST_PRECEDENCE, LOWEST_PRECEDENCE