Harmonize `accesslog.enabled` flag for Undertow

Closes gh-12178

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/ServerProperties.java

@@ -1058,7 +1058,7 @@ public class ServerProperties {
 			/**
 			 * Whether to enable the access log.
 			 */
-			private Boolean enabled;
+			private boolean enabled = false;
 
 			/**
 			 * Format pattern for access logs.
@@ -1085,11 +1085,11 @@ public class ServerProperties {
 			 */
 			private boolean rotate = true;
 
-			public Boolean getEnabled() {
+			public boolean isEnabled() {
 				return this.enabled;
 			}
 
-			public void setEnabled(Boolean enabled) {
+			public void setEnabled(boolean enabled) {
 				this.enabled = enabled;
 			}
 

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/embedded/UndertowWebServerFactoryCustomizer.java

@@ -69,7 +69,7 @@ public class UndertowWebServerFactoryCustomizer implements
 				.to(factory::setWorkerThreads);
 		propertyMapper.from(undertowProperties::getDirectBuffers)
 				.to(factory::setUseDirectBuffers);
-		propertyMapper.from(accesslogProperties::getEnabled)
+		propertyMapper.from(accesslogProperties::isEnabled)
 				.to(factory::setAccessLogEnabled);
 		propertyMapper.from(accesslogProperties::getDir)
 				.to(factory::setAccessLogDirectory);

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/embedded/UndertowWebServerFactoryCustomizerTests.java

@@ -29,9 +29,7 @@ import org.springframework.boot.web.embedded.undertow.ConfigurableUndertowWebSer
 import org.springframework.mock.env.MockEnvironment;
 import org.springframework.test.context.support.TestPropertySourceUtils;
 
-import static org.mockito.ArgumentMatchers.anyBoolean;
 import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
 
 /**
@@ -102,14 +100,6 @@ public class UndertowWebServerFactoryCustomizerTests {
 		verify(factory).setUseForwardHeaders(true);
 	}
 
-	@Test
-	public void skipNullElementsForUndertow() {
-		ConfigurableUndertowWebServerFactory factory = mock(
-				ConfigurableUndertowWebServerFactory.class);
-		this.customizer.customize(factory);
-		verify(factory, never()).setAccessLogEnabled(anyBoolean());
-	}
-
 	private void bind(String... inlinedProperties) {
 		TestPropertySourceUtils.addInlinedPropertiesToEnvironment(this.environment,
 				inlinedProperties);