Deprecate ClientHttpRequestFactories

Deprecate `ClientHttpRequestFactories` and refactor its internals to
delegate to the new `ClientHttpRequestFactoryBuilder` interface.

Closes gh-36266

Author: philwebb

spring-boot-project/spring-boot-docs/src/docs/antora/modules/reference/pages/io/rest-client.adoc

@@ -125,7 +125,7 @@ The following code shows a typical example:
 
 include-code::MyService[]
 
-If you need to apply other customization in addition to an SSL bundle, you can use the `ClientHttpRequestFactorySettings` class with `ClientHttpRequestFactories`:
+If you need to apply other customization in addition to an SSL bundle, you can use the `ClientHttpRequestFactorySettings` class with `ClientHttpRequestFactoryBuilder`:
 
 include-code::settings/MyService[]
 

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/io/restclient/restclient/ssl/settings/MyService.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,9 +18,9 @@
 
 import java.time.Duration;
 
+import org.springframework.boot.http.client.ClientHttpRequestFactoryBuilder;
+import org.springframework.boot.http.client.ClientHttpRequestFactorySettings;
 import org.springframework.boot.ssl.SslBundles;
-import org.springframework.boot.web.client.ClientHttpRequestFactories;
-import org.springframework.boot.web.client.ClientHttpRequestFactorySettings;
 import org.springframework.http.client.ClientHttpRequestFactory;
 import org.springframework.stereotype.Service;
 import org.springframework.web.client.RestClient;
@@ -31,10 +31,10 @@ public class MyService {
 	private final RestClient restClient;
 
 	public MyService(RestClient.Builder restClientBuilder, SslBundles sslBundles) {
-		ClientHttpRequestFactorySettings settings = ClientHttpRequestFactorySettings.DEFAULTS
-			.withReadTimeout(Duration.ofMinutes(2))
-			.withSslBundle(sslBundles.getBundle("mybundle"));
-		ClientHttpRequestFactory requestFactory = ClientHttpRequestFactories.get(settings);
+		ClientHttpRequestFactorySettings settings = ClientHttpRequestFactorySettings
+			.ofSslBundle(sslBundles.getBundle("mybundle"))
+			.withReadTimeout(Duration.ofMinutes(2));
+		ClientHttpRequestFactory requestFactory = ClientHttpRequestFactoryBuilder.detect().build(settings);
 		this.restClient = restClientBuilder.baseUrl("https://example.org").requestFactory(requestFactory).build();
 	}
 

spring-boot-project/spring-boot-docs/src/main/kotlin/org/springframework/boot/docs/io/restclient/restclient/ssl/settings/MyService.kt

@@ -16,9 +16,9 @@
 
 package org.springframework.boot.docs.io.restclient.restclient.ssl.settings
 
+import org.springframework.boot.http.client.ClientHttpRequestFactoryBuilder;
+import org.springframework.boot.http.client.ClientHttpRequestFactorySettings;
 import org.springframework.boot.ssl.SslBundles
-import org.springframework.boot.web.client.ClientHttpRequestFactories
-import org.springframework.boot.web.client.ClientHttpRequestFactorySettings
 import org.springframework.stereotype.Service
 import org.springframework.web.client.RestClient
 import java.time.Duration
@@ -29,10 +29,10 @@ class MyService(restClientBuilder: RestClient.Builder, sslBundles: SslBundles) {
 	private val restClient: RestClient
 
 	init {
-		val settings = ClientHttpRequestFactorySettings.DEFAULTS
+		val settings = ClientHttpRequestFactorySettings.defaults()
 				.withReadTimeout(Duration.ofMinutes(2))
 				.withSslBundle(sslBundles.getBundle("mybundle"))
-		val requestFactory = ClientHttpRequestFactories.get(settings)
+		val requestFactory = ClientHttpRequestFactoryBuilder.detect().build(settings);
 		restClient = restClientBuilder
 				.baseUrl("https://example.org")
 				.requestFactory(requestFactory).build()