SpringWebClientInternals.md

By default, HttpClient participates in the global Reactor Netty resources held in reactor.netty.http.HttpResources, including event loop threads and a connection pool. This is the recommended mode, since fixed, shared resources are preferred for event loop concurrency. In this mode global resources remain active until the process exits.

ReactorClientHttpConnector
ClientHttpConnector

https://docs.spring.io/spring/docs/current/spring-framework-reference/web-reactive.html#webflux-client-builder

https://github.com/spring-projects/spring-framework/blob/master/spring-web/src/main/java/org/springframework/http/client/reactive/ReactorClientHttpConnector.java

https://github.com/spring-projects/spring-framework/blob/master/spring-messaging/src/main/java/org/springframework/messaging/tcp/reactor/ReactorNettyTcpClient.java

public ReactorNettyTcpClient(String host, int port, ReactorNettyCodec<P> codec) {
		Assert.notNull(host, "host is required");
		Assert.notNull(codec, "ReactorNettyCodec is required");

		this.channelGroup = new DefaultChannelGroup(ImmediateEventExecutor.INSTANCE);
		this.loopResources = LoopResources.create("tcp-client-loop");
		this.poolResources = ConnectionProvider.elastic("tcp-client-pool");
		this.codec = codec;

		this.tcpClient = TcpClient.create(this.poolResources)
				.host(host).port(port)
				.runOn(this.loopResources, false)
				.doOnConnected(conn -> this.channelGroup.add(conn.channel()));
	}