Polish

See gh-43498

CONTRIBUTING.adoc

@@ -43,7 +43,7 @@ None of these is essential for a pull request, but they will all help.  They can
 added after the original pull request but before a merge.
 
 * We use the https://github.com/spring-io/spring-javaformat/[Spring JavaFormat] project to apply code formatting conventions.
-  If you use Eclipse and you follow the https://github.com/spring-projects/spring-boot/wiki/Working-with-the-Code#importing-into-eclipse["Importing into eclipse"] instructions you should get project specific formatting automatically.
+  If you use Eclipse and you follow the https://github.com/spring-projects/spring-boot/wiki/Working-with-the-Code#importing-into-eclipse["Importing into Eclipse"] instructions you should get project-specific formatting automatically.
   You can also install the https://github.com/spring-io/spring-javaformat/#intellij-idea[Spring JavaFormat IntelliJ Plugin] or format the code from the Gradle build by running `./gradlew format`.
   Note that if you have format violations in `buildSrc`, you can fix them by running `./gradlew -p buildSrc format` from the project root directory.
 * The build includes Checkstyle rules for many of our code conventions. Run `./gradlew checkstyleMain checkstyleTest` if you want to check your changes are compliant.

buildSrc/src/main/java/org/springframework/boot/build/bom/CheckBom.java

@@ -216,7 +216,7 @@ public abstract class CheckBom extends DefaultTask {
 			.getResolvedConfiguration()
 			.getResolvedArtifacts();
 		if (artifacts.size() != 1) {
-			throw new IllegalStateException("Expected a single file but '%s' resolved to %d artifacts"
+			throw new IllegalStateException("Expected a single artifact but '%s' resolved to %d artifacts"
 				.formatted(coordinates, artifacts.size()));
 		}
 		return artifacts.iterator().next().getFile();

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/logging/OnEnabledLoggingExportCondition.java

@@ -42,12 +42,13 @@ class OnEnabledLoggingExportCondition extends SpringBootCondition {
 	public ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeMetadata metadata) {
 		String loggingExporter = getExporterName(metadata);
 		if (StringUtils.hasLength(loggingExporter)) {
+			String formattedExporterProperty = EXPORTER_PROPERTY.formatted(loggingExporter);
 			Boolean exporterLoggingEnabled = context.getEnvironment()
-				.getProperty(EXPORTER_PROPERTY.formatted(loggingExporter), Boolean.class);
+				.getProperty(formattedExporterProperty, Boolean.class);
 			if (exporterLoggingEnabled != null) {
 				return new ConditionOutcome(exporterLoggingEnabled,
 						ConditionMessage.forCondition(ConditionalOnEnabledLoggingExport.class)
-							.because(EXPORTER_PROPERTY.formatted(loggingExporter) + " is " + exporterLoggingEnabled));
+							.because(formattedExporterProperty + " is " + exporterLoggingEnabled));
 			}
 		}
 		Boolean globalLoggingEnabled = context.getEnvironment().getProperty(GLOBAL_PROPERTY, Boolean.class);

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

@@ -209,8 +209,8 @@ If multiple clients are available on the classpath, and not global configuration
 [[io.rest-client.clienthttprequestfactory.configuration]]
 === Global HTTP Client Configuration
 
-If the the auto-detected HTTP client does not meet your needs, you can use the configprop:spring.http.client.factory[] property to pick a specific factory.
+If the auto-detected HTTP client does not meet your needs, you can use the configprop:spring.http.client.factory[] property to pick a specific factory.
-For example, if you have Apache HttpClient on your classpath, but you prefer Jetty's javadoc:org.eclipse.jetty.client.HttpClient[] you can add use the following:
+For example, if you have Apache HttpClient on your classpath, but you prefer Jetty's javadoc:org.eclipse.jetty.client.HttpClient[] you can add the following:
 
 [configprops,yaml]
 ----

spring-boot-project/spring-boot-docs/src/main/kotlin/org/springframework/boot/docs/io/restclient/clienthttprequestfactory/configuration/MyClientHttpConfiguration.kt

@@ -10,7 +10,7 @@ import java.net.http.HttpClient
 class MyClientHttpConfiguration {
 
 	@Bean
-	fun clientHttpRequestFactoryBuilder(proxySelector: ProxySelector): ClientHttpRequestFactoryBuilder<*>? {
+	fun clientHttpRequestFactoryBuilder(proxySelector: ProxySelector): ClientHttpRequestFactoryBuilder<*> {
 		return ClientHttpRequestFactoryBuilder.jdk()
 				.withHttpClientCustomizer { builder -> builder.proxy(proxySelector) }
 	}

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/json/app/ExampleJsonComponent.java

@@ -59,7 +59,7 @@ public class ExampleJsonComponent {
 		protected ExampleCustomObject deserializeObject(JsonParser jsonParser, DeserializationContext context,
 				ObjectCodec codec, JsonNode tree) throws IOException {
 			String value = nullSafeValue(tree.get("value"), String.class);
-			Date date = nullSafeValue(tree.get("date"), Integer.class, Date::new);
+			Date date = nullSafeValue(tree.get("date"), Long.class, Date::new);
 			UUID uuid = nullSafeValue(tree.get("uuid"), String.class, UUID::fromString);
 			return new ExampleCustomObject(value, date, uuid);
 		}

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/util/Instantiator.java

@@ -149,9 +149,9 @@ public class Instantiator<T> {
 	}
 
 	/**
-	 * Instantiate the given set of classes, injecting constructor arguments as necessary.
+	 * Instantiate the given class, injecting constructor arguments as necessary.
-	 * @param type the types to instantiate
+	 * @param type the type to instantiate
-	 * @return a list of instantiated instances
+	 * @return an instantiated instance
 	 * @since 3.4.0
 	 */
 	public T instantiateType(Class<?> type) {

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/context/ServerPortInfoApplicationContextInitializer.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.

spring-boot-tests/spring-boot-integration-tests/spring-boot-server-tests/src/intTest/java/org/springframework/boot/context/embedded/EmbeddedServerContainerInvocationContextProvider.java

@@ -116,8 +116,9 @@ class EmbeddedServerContainerInvocationContextProvider
 	private AbstractApplicationLauncher getAbstractApplicationLauncher(Application application,
 			Class<? extends AbstractApplicationLauncher> launcherClass) {
 		String cacheKey = application.getContainer() + ":" + application.getPackaging() + ":" + launcherClass.getName();
-		if (this.launcherCache.containsKey(cacheKey)) {
+		AbstractApplicationLauncher cachedLauncher = this.launcherCache.get(cacheKey);
-			return this.launcherCache.get(cacheKey);
+		if (cachedLauncher != null) {
+			return cachedLauncher;
 		}
 		AbstractApplicationLauncher launcher = ReflectionUtils.newInstance(launcherClass, application,
 				new File(buildOutput.getRootLocation(), "app-launcher-" + UUID.randomUUID()));