//okhttp/okhttp3/OkHttpClient/Builder/protocols

protocols

[jvm]\ fun protocols(protocols: List<Protocol>): OkHttpClient.Builder

Configure the protocols used by this client to communicate with remote servers. By default this client will prefer the most efficient transport available, falling back to more ubiquitous protocols. Applications should only call this method to avoid specific compatibility problems, such as web servers that behave incorrectly when HTTP/2 is enabled.

The following protocols are currently supported:

• http/1.1
• h2
• h2 with prior knowledge(cleartext only)

This is an evolving set. Future releases include support for transitional protocols. The http/1.1 transport will never be dropped.

If multiple protocols are specified, ALPN will be used to negotiate a transport. Protocol negotiation is only attempted for HTTPS URLs.

Protocol.HTTP_1_0 is not supported in this set. Requests are initiated with HTTP/1.1. If the server responds with HTTP/1.0, that will be exposed by Response.protocol.

Parameters

jvm

protocols	the protocols to use, in order of preference. If the list contains Protocol.H2_PRIOR_KNOWLEDGE then that must be the only protocol and HTTPS URLs will not be supported. Otherwise the list must contain Protocol.HTTP_1_1. The list must not contain null or Protocol.HTTP_1_0.