Only use AprLifecycleListener when native library is available

Closes gh-16040

Author: wilkinsona

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/tomcat/TomcatReactiveWebServerFactory.java

@@ -22,7 +22,6 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.List;
 
 import org.apache.catalina.Context;
@@ -67,8 +66,7 @@ public class TomcatReactiveWebServerFactory extends AbstractReactiveWebServerFac
 
 	private List<Valve> engineValves = new ArrayList<>();
 
-	private List<LifecycleListener> contextLifecycleListeners = new ArrayList<>(
-			Collections.singleton(new AprLifecycleListener()));
+	private List<LifecycleListener> contextLifecycleListeners = getDefaultLifecycleListeners();
 
 	private List<TomcatContextCustomizer> tomcatContextCustomizers = new ArrayList<>();
 
@@ -95,6 +93,13 @@ public TomcatReactiveWebServerFactory(int port) {
 		super(port);
 	}
 
+	private static List<LifecycleListener> getDefaultLifecycleListeners() {
+		AprLifecycleListener aprLifecycleListener = new AprLifecycleListener();
+		return AprLifecycleListener.isAprAvailable()
+				? new ArrayList<>(Arrays.asList(aprLifecycleListener))
+				: new ArrayList<>();
+	}
+
 	@Override
 	public WebServer getWebServer(HttpHandler httpHandler) {
 		Tomcat tomcat = new Tomcat();

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/tomcat/TomcatServletWebServerFactory.java

@@ -111,8 +111,7 @@ public class TomcatServletWebServerFactory extends AbstractServletWebServerFacto
 
 	private List<Valve> contextValves = new ArrayList<>();
 
-	private List<LifecycleListener> contextLifecycleListeners = new ArrayList<>(
-			Collections.singleton(new AprLifecycleListener()));
+	private List<LifecycleListener> contextLifecycleListeners = getDefaultLifecycleListeners();
 
 	private List<TomcatContextCustomizer> tomcatContextCustomizers = new ArrayList<>();
 
@@ -155,6 +154,13 @@ public TomcatServletWebServerFactory(String contextPath, int port) {
 		super(contextPath, port);
 	}
 
+	private static List<LifecycleListener> getDefaultLifecycleListeners() {
+		AprLifecycleListener aprLifecycleListener = new AprLifecycleListener();
+		return AprLifecycleListener.isAprAvailable()
+				? new ArrayList<>(Arrays.asList(aprLifecycleListener))
+				: new ArrayList<>();
+	}
+
 	@Override
 	public WebServer getWebServer(ServletContextInitializer... initializers) {
 		Tomcat tomcat = new Tomcat();

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/embedded/tomcat/TomcatReactiveWebServerFactoryTests.java

@@ -82,8 +82,13 @@ public void contextIsAddedToHostBeforeCustomizersAreCalled() {
 	@Test
 	public void defaultTomcatListeners() {
 		TomcatReactiveWebServerFactory factory = getFactory();
-		assertThat(factory.getContextLifecycleListeners()).hasSize(1).first()
-				.isInstanceOf(AprLifecycleListener.class);
+		if (AprLifecycleListener.isAprAvailable()) {
+			assertThat(factory.getContextLifecycleListeners()).hasSize(1).first()
+					.isInstanceOf(AprLifecycleListener.class);
+		}
+		else {
+			assertThat(factory.getContextLifecycleListeners()).isEmpty();
+		}
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/embedded/tomcat/TomcatServletWebServerFactoryTests.java

@@ -134,8 +134,13 @@ public void tomcatEngineNames() {
 	@Test
 	public void defaultTomcatListeners() {
 		TomcatServletWebServerFactory factory = getFactory();
-		assertThat(factory.getContextLifecycleListeners()).hasSize(1).first()
-				.isInstanceOf(AprLifecycleListener.class);
+		if (AprLifecycleListener.isAprAvailable()) {
+			assertThat(factory.getContextLifecycleListeners()).hasSize(1).first()
+					.isInstanceOf(AprLifecycleListener.class);
+		}
+		else {
+			assertThat(factory.getContextLifecycleListeners()).isEmpty();
+		}
 	}
 
 	@Test