[[webmvc-client]]
= REST Clients

This section describes options for client-side access to REST endpoints.




[[webmvc-resttemplate]]
== `RestTemplate`

`RestTemplate` is a synchronous client to perform HTTP requests. It is the original
Spring REST client and exposes a simple, template-method API over underlying HTTP client
libraries.

NOTE: As of 5.0 the `RestTemplate` is in maintenance mode, with only requests for minor
changes and bugs to be accepted. Please, consider using the
<<web-reactive.adoc#webflux-client, WebClient>> which offers a more modern API and
supports sync, async, and streaming scenarios.

See <<integration.adoc#rest-client-access, REST Endpoints>> for details.




[[webmvc-webclient]]
== `WebClient`

`WebClient` is a non-blocking, reactive client to perform HTTP requests. It was
introduced in 5.0 and offers a modern alternative to the `RestTemplate`, with efficient
support for both synchronous and asynchronous, as well as streaming scenarios.

In contrast to `RestTemplate`, `WebClient` supports the following:

* Non-blocking I/O.
* Reactive Streams back pressure.
* High concurrency with fewer hardware resources.
* Functional-style, fluent API that takes advantage of Java 8 lambdas.
* Synchronous and asynchronous interactions.
* Streaming up to or streaming down from a server.

See <<web-reactive.adoc#webflux-client, WebClient>> for more details.




[[webmvc-http-interface]]
== HTTP Interface

The Spring Frameworks lets you define an HTTP service as a Java interface with HTTP
exchange methods. You can then generate a proxy that implements this interface and
performs the exchanges. This helps to simplify HTTP remote access and provides additional
flexibility for to choose an API style such as synchronous or reactive.

See <<integration.adoc#rest-http-interface, REST Endpoints>> for details.
