replace lambda with method reference

Author: PiyalAhmed

buildSrc/src/main/java/org/springframework/boot/build/mavenplugin/MavenPluginPlugin.java

@@ -55,6 +55,7 @@
 import org.gradle.api.attributes.DocsType;
 import org.gradle.api.attributes.Usage;
 import org.gradle.api.component.AdhocComponentWithVariants;
+import org.gradle.api.component.ConfigurationVariantDetails;
 import org.gradle.api.component.SoftwareComponent;
 import org.gradle.api.file.CopySpec;
 import org.gradle.api.file.DirectoryProperty;
@@ -132,7 +133,7 @@ private void publishOptionalDependenciesInPom(Project project) {
 			if (component instanceof AdhocComponentWithVariants componentWithVariants) {
 				componentWithVariants.addVariantsFromConfiguration(
 						project.getConfigurations().getByName(OptionalDependenciesPlugin.OPTIONAL_CONFIGURATION_NAME),
-						(variant) -> variant.mapToOptional());
+						ConfigurationVariantDetails::mapToOptional);
 			}
 		});
 		MavenPublication publication = (MavenPublication) project.getExtensions()

spring-boot-project/spring-boot-tools/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/BootArchiveSupport.java

@@ -150,11 +150,11 @@ CopyAction createCopyAction(Jar jar, ResolvedDependencies resolvedDependencies,
 	}
 
 	private Integer getDirMode(CopySpec copySpec) {
-		return getMode(copySpec, "getDirPermissions", () -> copySpec.getDirMode());
+		return getMode(copySpec, "getDirPermissions", copySpec::getDirMode);
 	}
 
 	private Integer getFileMode(CopySpec copySpec) {
-		return getMode(copySpec, "getFilePermissions", () -> copySpec.getFileMode());
+		return getMode(copySpec, "getFilePermissions", copySpec::getFileMode);
 	}
 
 	@SuppressWarnings("unchecked")