Class DmxHttpClient

java.lang.Object

dmx.fun.http.DmxHttpClient

@NullMarked
public final class DmxHttpClient
extends Object

A thin wrapper around HttpClient that returns Result<T, HttpError> instead of throwing exceptions.

Both network failures (IOException, InterruptedException) and HTTP error status codes (4xx, 5xx) are surfaced as typed HttpError variants, collapsing two separate failure modes into one:

DmxHttpClient client = DmxHttpClient.of(HttpClient.newHttpClient());

client.send(request, BodyHandlers.ofString())
    .peek(body -> process(body))
    .peekError(err -> log.warn("HTTP call failed: {}", err));

Limitation: null-body handlers are not supported

Body handlers that produce a null body — specifically HttpResponse.BodyHandlers.discarding() — are not supported. Result.ok() does not accept null values, so passing a null-body handler will throw NullPointerException on a successful response.

If you need to send a request and ignore the response body, use the plain HttpClient directly, or wait for a future sendDiscarding() overload.

Method Summary

Modifier and Type	Method	Description
static DmxHttpClient	of(HttpClient client)	Creates a new DmxHttpClient wrapping the given HttpClient.
<T> Result<T, HttpError>	send(HttpRequest request, HttpResponse.BodyHandler<T> bodyHandler)	Sends an HTTP request synchronously and returns the result.
<T,R> Result<R, HttpError>	send(HttpRequest request, HttpResponse.BodyHandler<T> bodyHandler, CheckedFunction<T,R> deserializer)	Sends an HTTP request synchronously, then applies deserializer to the body.
<T> CompletableFuture<Result<T, HttpError>>	sendAsync(HttpRequest request, HttpResponse.BodyHandler<T> bodyHandler)	Sends an HTTP request asynchronously and returns a CompletableFuture that completes with a Result.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

of

public static DmxHttpClient of(HttpClient client)

Creates a new DmxHttpClient wrapping the given HttpClient.

Parameters:

client - the underlying JDK HTTP client; must not be null

Returns:

a new DmxHttpClient

send

public <T> Result<T, HttpError> send(HttpRequest request,
 HttpResponse.BodyHandler<T> bodyHandler)

Sends an HTTP request synchronously and returns the result.

Status mapping:

• 2xx / 3xx → Result.ok(body)
• 4xx → Result.err(ClientError)
• 5xx → Result.err(ServerError)
• HttpTimeoutException → Result.err(Timeout)
• IOException / InterruptedException → Result.err(NetworkFailure)

Type Parameters:

T - the body type

Parameters:

request - the request to send; must not be null

bodyHandler - the response body handler; must not be null

Returns:

a Result wrapping the body or an HttpError

send

public <T,R> Result<R, HttpError> send(HttpRequest request,
 HttpResponse.BodyHandler<T> bodyHandler,
 CheckedFunction<T,R> deserializer)

Sends an HTTP request synchronously, then applies deserializer to the body.

If the HTTP call succeeds but deserializer throws, the exception is wrapped in a HttpError.NetworkFailure.

Type Parameters:

T - the raw body type produced by bodyHandler

R - the deserialized value type

Parameters:

request - the request to send; must not be null

bodyHandler - the response body handler; must not be null

deserializer - function applied to the raw body on success; must not be null

Returns:

a Result wrapping the deserialized value or an HttpError

sendAsync

public <T> CompletableFuture<Result<T, HttpError>> sendAsync(HttpRequest request,
 HttpResponse.BodyHandler<T> bodyHandler)

Sends an HTTP request asynchronously and returns a CompletableFuture that completes with a Result.

The returned future never completes exceptionally — transport failures are wrapped in HttpError.NetworkFailure or HttpError.Timeout.

Type Parameters:

T - the body type

Parameters:

request - the request to send; must not be null

bodyHandler - the response body handler; must not be null

Returns:

a future that completes with a Result wrapping the body or an HttpError