Interface HttpOption<T>

Type Parameters:: T - The type of the option value

public sealed interface HttpOption<T>

This interface is used to provide additional request configuration option hints on how an HTTP request/response exchange should be carried out by the HttpClient implementation. Request configuration option hints can be provided to an HttpRequest with the

HttpRequest.Builder
setOption

method.

Concrete instances of this class and its subclasses are immutable.

API Note:: In this version, the HttpOption interface is sealed and only allows the H3_DISCOVERY option. However, it could be extended in the future to support additional options.
The H3_DISCOVERY option can be used to help the HttpClient decide how to select or establish an HTTP/3 connection through which to carry out an HTTP/3 request/response exchange.
Since:: 26

Nested Class Summary

Modifier and Type	Interface	Description
`static enum`	`HttpOption.Http3DiscoveryMode`	This enumeration can be used to help the `HttpClient` decide how an HTTP/3 exchange should be established, and can be provided as the value of the `H3_DISCOVERY` option to `Builder.setOption`.

Field Summary

Modifier and Type	Field	Description
`static final HttpOption<HttpOption.Http3DiscoveryMode>`	`H3_DISCOVERY`	An option that can be used to configure how the `HttpClient` will select or establish an HTTP/3 connection through which to carry out the request.

Method Summary

Modifier and Type	Method	Description
`String`	`name()`	Returns the option name.
`Class<T>`	`type()`	Returns the type of the value associated with the option.

Field Details

H3_DISCOVERY

static final HttpOption<HttpOption.Http3DiscoveryMode> H3_DISCOVERY

An option that can be used to configure how the HttpClient will select or establish an HTTP/3 connection through which to carry out the request. If HttpClient.Version.HTTP_3 is not selected either as the request preferred version or the HttpClient preferred version setting this option on the request has no effect.

The name of this option is "H3_DISCOVERY".

Implementation Note:

The JDK built-in implementation of the HttpClient understands the request option H3_DISCOVERY hint.
If no H3_DISCOVERY hint is provided, and the HTTP/3 version is selected, either as request preferred version or client preferred version, the JDK built-in implementation will establish the exchange as per HttpOption.Http3DiscoveryMode.ANY.

In case of redirect, the H3_DISCOVERY option, if present, is always transferred to the new request.

In this implementation, HTTP/3 through proxies is not supported. Unless HttpOption.Http3DiscoveryMode.HTTP_3_URI_ONLY is specified, if a proxy is selected for the request URI, the protocol version is downgraded to HTTP/2 or HTTP/1.1 and the H3_DISCOVERY option is ignored. If, on the other hand, HttpOption.Http3DiscoveryMode.HTTP_3_URI_ONLY is specified, the request will fail.

See Also:

Method Details

name

String name()

Returns the option name.

Implementation Requirements:: Different options must have different names.
Returns:: the option name

type

Class<T> type()

Returns the type of the value associated with the option.

API Note:: Different options may have the same type.
Returns:: the type of the value associated with the option

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