selectPreferredLanguage

Description

Inspects the request's Accept-Language header and determines, which of a given set of language alternatives is preferred by the client according to content negotiation rules defined by http://tools.ietf.org/html/rfc7231#section-5.3.5.

If there are several best language alternatives that the client has equal preference for (even if this preference is zero!) the order of the arguments is used as a tie breaker (first one wins).

Example

TODO: Example snippets for JavaDSL are subject to community contributions! Help us complete the docs, read more about it here: write example snippets for Akka HTTP Java DSL #20466.