Add nullability annotations to module/spring-boot-http-client

See gh-46587

Author: mhalbritter

module/spring-boot-http-client/src/main/java/org/springframework/boot/http/client/AbstractClientHttpRequestFactoryBuilder.java

@@ -22,8 +22,11 @@
 import java.util.List;
 import java.util.function.Consumer;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.boot.util.LambdaSafe;
 import org.springframework.http.client.ClientHttpRequestFactory;
+import org.springframework.lang.Contract;
 import org.springframework.util.Assert;
 
 /**
@@ -37,7 +40,7 @@ abstract class AbstractClientHttpRequestFactoryBuilder<T extends ClientHttpReque
 
 	private final List<Consumer<T>> customizers;
 
-	protected AbstractClientHttpRequestFactoryBuilder(List<Consumer<T>> customizers) {
+	protected AbstractClientHttpRequestFactoryBuilder(@Nullable List<Consumer<T>> customizers) {
 		this.customizers = (customizers != null) ? customizers : Collections.emptyList();
 	}
 
@@ -64,7 +67,7 @@ private <E> List<E> merge(Collection<E> list, Collection<? extends E> additional
 
 	@Override
 	@SuppressWarnings("unchecked")
-	public final T build(ClientHttpRequestFactorySettings settings) {
+	public final T build(@Nullable ClientHttpRequestFactorySettings settings) {
 		T factory = createClientHttpRequestFactory(
 				(settings != null) ? settings : ClientHttpRequestFactorySettings.defaults());
 		LambdaSafe.callbacks(Consumer.class, this.customizers, factory).invoke((consumer) -> consumer.accept(factory));
@@ -73,7 +76,9 @@ public final T build(ClientHttpRequestFactorySettings settings) {
 
 	protected abstract T createClientHttpRequestFactory(ClientHttpRequestFactorySettings settings);
 
-	protected final HttpClientSettings asHttpClientSettings(ClientHttpRequestFactorySettings settings) {
+	@Contract("!null -> !null")
+	protected final @Nullable HttpClientSettings asHttpClientSettings(
+			@Nullable ClientHttpRequestFactorySettings settings) {
 		return (settings != null) ? new HttpClientSettings(settings.redirects(), settings.connectTimeout(),
 				settings.readTimeout(), settings.sslBundle()) : null;
 	}

module/spring-boot-http-client/src/main/java/org/springframework/boot/http/client/ClientHttpRequestFactoryBuilder.java

@@ -21,6 +21,8 @@
 import java.util.function.Consumer;
 import java.util.function.Supplier;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.boot.util.LambdaSafe;
 import org.springframework.http.client.ClientHttpRequestFactory;
 import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
@@ -59,7 +61,7 @@ default T build() {
 	 * @param settings the settings to apply or {@code null}
 	 * @return a fully configured {@link ClientHttpRequestFactory}.
 	 */
-	T build(ClientHttpRequestFactorySettings settings);
+	T build(@Nullable ClientHttpRequestFactorySettings settings);
 
 	/**
 	 * Return a new {@link ClientHttpRequestFactoryBuilder} that applies the given
@@ -213,7 +215,8 @@ static ClientHttpRequestFactoryBuilder<? extends ClientHttpRequestFactory> detec
 	 * @return the most suitable {@link ClientHttpRequestFactoryBuilder} for the classpath
 	 * @since 3.5.0
 	 */
-	static ClientHttpRequestFactoryBuilder<? extends ClientHttpRequestFactory> detect(ClassLoader classLoader) {
+	static ClientHttpRequestFactoryBuilder<? extends ClientHttpRequestFactory> detect(
+			@Nullable ClassLoader classLoader) {
 		if (HttpComponentsClientHttpRequestFactoryBuilder.Classes.present(classLoader)) {
 			return httpComponents();
 		}

module/spring-boot-http-client/src/main/java/org/springframework/boot/http/client/ClientHttpRequestFactoryRuntimeHints.java

@@ -20,6 +20,8 @@
 import java.lang.reflect.Method;
 import java.net.HttpURLConnection;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.aot.hint.ExecutableMode;
 import org.springframework.aot.hint.ReflectionHints;
 import org.springframework.aot.hint.RuntimeHints;
@@ -45,13 +47,13 @@
 class ClientHttpRequestFactoryRuntimeHints implements RuntimeHintsRegistrar {
 
 	@Override
-	public void registerHints(RuntimeHints hints, ClassLoader classLoader) {
+	public void registerHints(RuntimeHints hints, @Nullable ClassLoader classLoader) {
 		if (ClassUtils.isPresent("org.springframework.http.client.ClientHttpRequestFactory", classLoader)) {
 			registerHints(hints.reflection(), classLoader);
 		}
 	}
 
-	private void registerHints(ReflectionHints hints, ClassLoader classLoader) {
+	private void registerHints(ReflectionHints hints, @Nullable ClassLoader classLoader) {
 		hints.registerField(findField(AbstractClientHttpRequestFactoryWrapper.class, "requestFactory"));
 		registerClientHttpRequestFactoryHints(hints, classLoader,
 				HttpComponentsClientHttpRequestFactoryBuilder.Classes.HTTP_CLIENTS,
@@ -71,8 +73,8 @@ private void registerHints(ReflectionHints hints, ClassLoader classLoader) {
 		});
 	}
 
-	private void registerClientHttpRequestFactoryHints(ReflectionHints hints, ClassLoader classLoader, String className,
-			Runnable action) {
+	private void registerClientHttpRequestFactoryHints(ReflectionHints hints, @Nullable ClassLoader classLoader,
+			String className, Runnable action) {
 		hints.registerTypeIfPresent(classLoader, className, (typeHint) -> {
 			typeHint.onReachableType(TypeReference.of(className));
 			action.run();

module/spring-boot-http-client/src/main/java/org/springframework/boot/http/client/ClientHttpRequestFactorySettings.java

@@ -18,6 +18,8 @@
 
 import java.time.Duration;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.boot.ssl.SslBundle;
 import org.springframework.http.client.ClientHttpRequestFactory;
 
@@ -35,14 +37,18 @@
  * @since 3.4.0
  * @see ClientHttpRequestFactoryBuilder
  */
-public record ClientHttpRequestFactorySettings(HttpRedirects redirects, Duration connectTimeout, Duration readTimeout,
-		SslBundle sslBundle) {
+public record ClientHttpRequestFactorySettings(HttpRedirects redirects, @Nullable Duration connectTimeout,
+		@Nullable Duration readTimeout, @Nullable SslBundle sslBundle) {
 
 	private static final ClientHttpRequestFactorySettings defaults = new ClientHttpRequestFactorySettings(null, null,
 			null, null);
 
-	public ClientHttpRequestFactorySettings {
-		redirects = (redirects != null) ? redirects : HttpRedirects.FOLLOW_WHEN_POSSIBLE;
+	public ClientHttpRequestFactorySettings(@Nullable HttpRedirects redirects, @Nullable Duration connectTimeout,
+			@Nullable Duration readTimeout, @Nullable SslBundle sslBundle) {
+		this.redirects = (redirects != null) ? redirects : HttpRedirects.FOLLOW_WHEN_POSSIBLE;
+		this.connectTimeout = connectTimeout;
+		this.readTimeout = readTimeout;
+		this.sslBundle = sslBundle;
 	}
 
 	/**
@@ -51,7 +57,7 @@ public record ClientHttpRequestFactorySettings(HttpRedirects redirects, Duration
 	 * @param connectTimeout the new connect timeout setting
 	 * @return a new {@link ClientHttpRequestFactorySettings} instance
 	 */
-	public ClientHttpRequestFactorySettings withConnectTimeout(Duration connectTimeout) {
+	public ClientHttpRequestFactorySettings withConnectTimeout(@Nullable Duration connectTimeout) {
 		return new ClientHttpRequestFactorySettings(this.redirects, connectTimeout, this.readTimeout, this.sslBundle);
 	}
 
@@ -61,7 +67,7 @@ public ClientHttpRequestFactorySettings withConnectTimeout(Duration connectTimeo
 	 * @param readTimeout the new read timeout setting
 	 * @return a new {@link ClientHttpRequestFactorySettings} instance
 	 */
-	public ClientHttpRequestFactorySettings withReadTimeout(Duration readTimeout) {
+	public ClientHttpRequestFactorySettings withReadTimeout(@Nullable Duration readTimeout) {
 		return new ClientHttpRequestFactorySettings(this.redirects, this.connectTimeout, readTimeout, this.sslBundle);
 	}
 
@@ -72,7 +78,8 @@ public ClientHttpRequestFactorySettings withReadTimeout(Duration readTimeout) {
 	 * @param readTimeout the new read timeout setting
 	 * @return a new {@link ClientHttpRequestFactorySettings} instance
 	 */
-	public ClientHttpRequestFactorySettings withTimeouts(Duration connectTimeout, Duration readTimeout) {
+	public ClientHttpRequestFactorySettings withTimeouts(@Nullable Duration connectTimeout,
+			@Nullable Duration readTimeout) {
 		return new ClientHttpRequestFactorySettings(this.redirects, connectTimeout, readTimeout, this.sslBundle);
 	}
 
@@ -82,7 +89,7 @@ public ClientHttpRequestFactorySettings withTimeouts(Duration connectTimeout, Du
 	 * @param sslBundle the new SSL bundle setting
 	 * @return a new {@link ClientHttpRequestFactorySettings} instance
 	 */
-	public ClientHttpRequestFactorySettings withSslBundle(SslBundle sslBundle) {
+	public ClientHttpRequestFactorySettings withSslBundle(@Nullable SslBundle sslBundle) {
 		return new ClientHttpRequestFactorySettings(this.redirects, this.connectTimeout, this.readTimeout, sslBundle);
 	}
 
@@ -92,7 +99,7 @@ public ClientHttpRequestFactorySettings withSslBundle(SslBundle sslBundle) {
 	 * @param redirects the new redirects setting
 	 * @return a new {@link ClientHttpRequestFactorySettings} instance
 	 */
-	public ClientHttpRequestFactorySettings withRedirects(HttpRedirects redirects) {
+	public ClientHttpRequestFactorySettings withRedirects(@Nullable HttpRedirects redirects) {
 		return new ClientHttpRequestFactorySettings(redirects, this.connectTimeout, this.readTimeout, this.sslBundle);
 	}
 
@@ -102,7 +109,7 @@ public ClientHttpRequestFactorySettings withRedirects(HttpRedirects redirects) {
 	 * @param sslBundle the SSL bundle setting
 	 * @return a new {@link ClientHttpRequestFactorySettings} instance
 	 */
-	public static ClientHttpRequestFactorySettings ofSslBundle(SslBundle sslBundle) {
+	public static ClientHttpRequestFactorySettings ofSslBundle(@Nullable SslBundle sslBundle) {
 		return defaults().withSslBundle(sslBundle);
 	}
 

module/spring-boot-http-client/src/main/java/org/springframework/boot/http/client/HttpClientSettings.java

@@ -18,6 +18,8 @@
 
 import java.time.Duration;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.boot.ssl.SslBundle;
 
 /**
@@ -31,13 +33,17 @@
  * @author Phillip Webb
  * @since 3.5.0
  */
-public record HttpClientSettings(HttpRedirects redirects, Duration connectTimeout, Duration readTimeout,
-		SslBundle sslBundle) {
+public record HttpClientSettings(HttpRedirects redirects, @Nullable Duration connectTimeout,
+		@Nullable Duration readTimeout, @Nullable SslBundle sslBundle) {
 
 	static final HttpClientSettings DEFAULTS = new HttpClientSettings(null, null, null, null);
 
-	public HttpClientSettings {
-		redirects = (redirects != null) ? redirects : HttpRedirects.FOLLOW_WHEN_POSSIBLE;
+	public HttpClientSettings(@Nullable HttpRedirects redirects, @Nullable Duration connectTimeout,
+			@Nullable Duration readTimeout, @Nullable SslBundle sslBundle) {
+		this.redirects = (redirects != null) ? redirects : HttpRedirects.FOLLOW_WHEN_POSSIBLE;
+		this.connectTimeout = connectTimeout;
+		this.readTimeout = readTimeout;
+		this.sslBundle = sslBundle;
 	}
 
 }

module/spring-boot-http-client/src/main/java/org/springframework/boot/http/client/HttpComponentsClientHttpRequestFactoryBuilder.java

@@ -28,6 +28,7 @@
 import org.apache.hc.client5.http.impl.io.PoolingHttpClientConnectionManagerBuilder;
 import org.apache.hc.client5.http.ssl.TlsSocketStrategy;
 import org.apache.hc.core5.http.io.SocketConfig;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.boot.context.properties.PropertyMapper;
 import org.springframework.boot.ssl.SslBundle;
@@ -53,7 +54,7 @@ public final class HttpComponentsClientHttpRequestFactoryBuilder
 	}
 
 	private HttpComponentsClientHttpRequestFactoryBuilder(
-			List<Consumer<HttpComponentsClientHttpRequestFactory>> customizers,
+			@Nullable List<Consumer<HttpComponentsClientHttpRequestFactory>> customizers,
 			HttpComponentsHttpClientBuilder httpClientBuilder) {
 		super(customizers);
 		this.httpClientBuilder = httpClientBuilder;
@@ -121,7 +122,7 @@ public HttpComponentsClientHttpRequestFactoryBuilder withSocketConfigCustomizer(
 	 * @return a new {@link HttpComponentsClientHttpRequestFactoryBuilder} instance
 	 */
 	public HttpComponentsClientHttpRequestFactoryBuilder withTlsSocketStrategyFactory(
-			Function<SslBundle, TlsSocketStrategy> tlsSocketStrategyFactory) {
+			Function<@Nullable SslBundle, @Nullable TlsSocketStrategy> tlsSocketStrategyFactory) {
 		Assert.notNull(tlsSocketStrategyFactory, "'tlsSocketStrategyFactory' must not be null");
 		return new HttpComponentsClientHttpRequestFactoryBuilder(getCustomizers(),
 				this.httpClientBuilder.withTlsSocketStrategyFactory(tlsSocketStrategyFactory));
@@ -156,7 +157,7 @@ static class Classes {
 
 		static final String HTTP_CLIENTS = "org.apache.hc.client5.http.impl.classic.HttpClients";
 
-		static boolean present(ClassLoader classLoader) {
+		static boolean present(@Nullable ClassLoader classLoader) {
 			return ClassUtils.isPresent(HTTP_CLIENTS, classLoader);
 		}
 

module/spring-boot-http-client/src/main/java/org/springframework/boot/http/client/HttpComponentsHttpAsyncClientBuilder.java

@@ -29,6 +29,7 @@
 import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManager;
 import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManagerBuilder;
 import org.apache.hc.core5.http.nio.ssl.TlsStrategy;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.boot.context.properties.PropertyMapper;
 import org.springframework.boot.ssl.SslBundle;
@@ -54,7 +55,7 @@ public final class HttpComponentsHttpAsyncClientBuilder {
 
 	private final Consumer<RequestConfig.Builder> defaultRequestConfigCustomizer;
 
-	private final Function<SslBundle, TlsStrategy> tlsStrategyFactory;
+	private final Function<@Nullable SslBundle, @Nullable TlsStrategy> tlsStrategyFactory;
 
 	public HttpComponentsHttpAsyncClientBuilder() {
 		this(Empty.consumer(), Empty.consumer(), Empty.consumer(), Empty.consumer(),
@@ -65,7 +66,7 @@ private HttpComponentsHttpAsyncClientBuilder(Consumer<HttpAsyncClientBuilder> cu
 			Consumer<PoolingAsyncClientConnectionManagerBuilder> connectionManagerCustomizer,
 			Consumer<ConnectionConfig.Builder> connectionConfigCustomizer,
 			Consumer<RequestConfig.Builder> defaultRequestConfigCustomizer,
-			Function<SslBundle, TlsStrategy> tlsStrategyFactory) {
+			Function<@Nullable SslBundle, @Nullable TlsStrategy> tlsStrategyFactory) {
 		this.customizer = customizer;
 		this.connectionManagerCustomizer = connectionManagerCustomizer;
 		this.connectionConfigCustomizer = connectionConfigCustomizer;
@@ -123,7 +124,7 @@ public HttpComponentsHttpAsyncClientBuilder withConnectionConfigCustomizer(
 	 * @return a new {@link HttpComponentsHttpAsyncClientBuilder} instance
 	 */
 	public HttpComponentsHttpAsyncClientBuilder withTlsStrategyFactory(
-			Function<SslBundle, TlsStrategy> tlsStrategyFactory) {
+			Function<@Nullable SslBundle, @Nullable TlsStrategy> tlsStrategyFactory) {
 		Assert.notNull(tlsStrategyFactory, "'tlsStrategyFactory' must not be null");
 		return new HttpComponentsHttpAsyncClientBuilder(this.customizer, this.connectionManagerCustomizer,
 				this.connectionConfigCustomizer, this.defaultRequestConfigCustomizer, tlsStrategyFactory);
@@ -150,7 +151,7 @@ public HttpComponentsHttpAsyncClientBuilder withDefaultRequestConfigCustomizer(
 	 * @param settings the settings to apply
 	 * @return a new {@link CloseableHttpAsyncClient} instance
 	 */
-	public CloseableHttpAsyncClient build(HttpClientSettings settings) {
+	public CloseableHttpAsyncClient build(@Nullable HttpClientSettings settings) {
 		settings = (settings != null) ? settings : HttpClientSettings.DEFAULTS;
 		HttpAsyncClientBuilder builder = HttpAsyncClientBuilder.create()
 			.useSystemProperties()
@@ -166,11 +167,17 @@ private PoolingAsyncClientConnectionManager createConnectionManager(HttpClientSe
 			.useSystemProperties();
 		PropertyMapper map = PropertyMapper.get().alwaysApplyingWhenNonNull();
 		builder.setDefaultConnectionConfig(createConnectionConfig(settings));
-		map.from(settings::sslBundle).as(this.tlsStrategyFactory).to(builder::setTlsStrategy);
+		setTlsStrategy(settings, map, builder);
 		this.connectionManagerCustomizer.accept(builder);
 		return builder.build();
 	}
 
+	@SuppressWarnings("NullAway") // Lambda isn't detected with the correct nullability
+	private void setTlsStrategy(HttpClientSettings settings, PropertyMapper map,
+			PoolingAsyncClientConnectionManagerBuilder builder) {
+		map.from(settings::sslBundle).as(this.tlsStrategyFactory).to(builder::setTlsStrategy);
+	}
+
 	private ConnectionConfig createConnectionConfig(HttpClientSettings settings) {
 		ConnectionConfig.Builder builder = ConnectionConfig.custom();
 		PropertyMapper map = PropertyMapper.get().alwaysApplyingWhenNonNull();

module/spring-boot-http-client/src/main/java/org/springframework/boot/http/client/HttpComponentsHttpClientBuilder.java

@@ -29,6 +29,7 @@
 import org.apache.hc.client5.http.impl.io.PoolingHttpClientConnectionManagerBuilder;
 import org.apache.hc.client5.http.ssl.TlsSocketStrategy;
 import org.apache.hc.core5.http.io.SocketConfig;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.boot.context.properties.PropertyMapper;
 import org.springframework.boot.ssl.SslBundle;
@@ -54,7 +55,7 @@ public final class HttpComponentsHttpClientBuilder {
 
 	private final Consumer<RequestConfig.Builder> defaultRequestConfigCustomizer;
 
-	private final Function<SslBundle, TlsSocketStrategy> tlsSocketStrategyFactory;
+	private final Function<@Nullable SslBundle, @Nullable TlsSocketStrategy> tlsSocketStrategyFactory;
 
 	public HttpComponentsHttpClientBuilder() {
 		this(Empty.consumer(), Empty.consumer(), Empty.consumer(), Empty.consumer(),
@@ -65,7 +66,7 @@ private HttpComponentsHttpClientBuilder(Consumer<HttpClientBuilder> customizer,
 			Consumer<PoolingHttpClientConnectionManagerBuilder> connectionManagerCustomizer,
 			Consumer<SocketConfig.Builder> socketConfigCustomizer,
 			Consumer<RequestConfig.Builder> defaultRequestConfigCustomizer,
-			Function<SslBundle, TlsSocketStrategy> tlsSocketStrategyFactory) {
+			Function<@Nullable SslBundle, @Nullable TlsSocketStrategy> tlsSocketStrategyFactory) {
 		this.customizer = customizer;
 		this.connectionManagerCustomizer = connectionManagerCustomizer;
 		this.socketConfigCustomizer = socketConfigCustomizer;
@@ -125,7 +126,7 @@ public HttpComponentsHttpClientBuilder withSocketConfigCustomizer(
 	 * @return a new {@link HttpComponentsHttpClientBuilder} instance
 	 */
 	public HttpComponentsHttpClientBuilder withTlsSocketStrategyFactory(
-			Function<SslBundle, TlsSocketStrategy> tlsSocketStrategyFactory) {
+			Function<@Nullable SslBundle, @Nullable TlsSocketStrategy> tlsSocketStrategyFactory) {
 		Assert.notNull(tlsSocketStrategyFactory, "'tlsSocketStrategyFactory' must not be null");
 		return new HttpComponentsHttpClientBuilder(this.customizer, this.connectionManagerCustomizer,
 				this.socketConfigCustomizer, this.defaultRequestConfigCustomizer, tlsSocketStrategyFactory);
@@ -153,7 +154,7 @@ public HttpComponentsHttpClientBuilder withDefaultRequestConfigCustomizer(
 	 * @param settings the settings to apply
 	 * @return a new {@link HttpClient} instance
 	 */
-	public CloseableHttpClient build(HttpClientSettings settings) {
+	public CloseableHttpClient build(@Nullable HttpClientSettings settings) {
 		settings = (settings != null) ? settings : HttpClientSettings.DEFAULTS;
 		Assert.isTrue(settings.connectTimeout() == null, "'settings' must not have a 'connectTimeout'");
 		HttpClientBuilder builder = HttpClientBuilder.create()
@@ -170,11 +171,17 @@ private PoolingHttpClientConnectionManager createConnectionManager(HttpClientSet
 			.useSystemProperties();
 		PropertyMapper map = PropertyMapper.get();
 		builder.setDefaultSocketConfig(createSocketConfig(settings));
-		map.from(settings::sslBundle).as(this.tlsSocketStrategyFactory).whenNonNull().to(builder::setTlsSocketStrategy);
+		setTlsSocketStrategy(settings, map, builder);
 		this.connectionManagerCustomizer.accept(builder);
 		return builder.build();
 	}
 
+	@SuppressWarnings("NullAway") // Lambda isn't detected with the correct nullability
+	private void setTlsSocketStrategy(HttpClientSettings settings, PropertyMapper map,
+			PoolingHttpClientConnectionManagerBuilder builder) {
+		map.from(settings::sslBundle).as(this.tlsSocketStrategyFactory).whenNonNull().to(builder::setTlsSocketStrategy);
+	}
+
 	private SocketConfig createSocketConfig(HttpClientSettings settings) {
 		SocketConfig.Builder builder = SocketConfig.custom();
 		PropertyMapper map = PropertyMapper.get().alwaysApplyingWhenNonNull();