Finalize upgrade to Reactor Netty 0.8

This commit fixes the last issue for the upgrade to Reactor Netty 0.8.

Closes: gh-13321

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/netty/NettyWebServer.java

@@ -16,11 +16,11 @@
 
 package org.springframework.boot.web.embedded.netty;
 
-import java.net.BindException;
 import java.time.Duration;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import reactor.netty.ChannelBindException;
 import reactor.netty.DisposableServer;
 import reactor.netty.http.HttpResources;
 import reactor.netty.http.server.HttpServer;
@@ -69,8 +69,9 @@ public class NettyWebServer implements WebServer {
 				this.disposableServer = startHttpServer();
 			}
 			catch (Exception ex) {
-				if (findBindException(ex) != null) {
-					throw new PortInUseException(getPort());
+				ChannelBindException bindException = findBindException(ex);
+				if (bindException != null) {
+					throw new PortInUseException(bindException.localPort());
 				}
 				throw new WebServerException("Unable to start Netty", ex);
 			}
@@ -87,11 +88,11 @@ public class NettyWebServer implements WebServer {
 		return this.httpServer.handle(this.handlerAdapter).bindNow();
 	}
 
-	private BindException findBindException(Exception ex) {
+	private ChannelBindException findBindException(Exception ex) {
 		Throwable candidate = ex;
 		while (candidate != null) {
-			if (candidate instanceof BindException) {
-				return (BindException) candidate;
+			if (candidate instanceof ChannelBindException) {
+				return (ChannelBindException) candidate;
 			}
 			candidate = candidate.getCause();
 		}

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/embedded/netty/NettyReactiveWebServerFactoryTests.java

@@ -18,14 +18,14 @@ package org.springframework.boot.web.embedded.netty;
 
 import java.util.Arrays;
 
-import org.junit.Ignore;
+import org.hamcrest.Matchers;
 import org.junit.Test;
 import org.mockito.InOrder;
 import reactor.netty.http.server.HttpServer;
 
 import org.springframework.boot.web.reactive.server.AbstractReactiveWebServerFactory;
 import org.springframework.boot.web.reactive.server.AbstractReactiveWebServerFactoryTests;
-import org.springframework.boot.web.server.WebServerException;
+import org.springframework.boot.web.server.PortInUseException;
 
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.BDDMockito.given;
@@ -46,14 +46,15 @@ public class NettyReactiveWebServerFactoryTests
 	}
 
 	@Test
-	@Ignore
 	public void exceptionIsThrownWhenPortIsAlreadyInUse() {
 		AbstractReactiveWebServerFactory factory = getFactory();
 		factory.setPort(0);
 		this.webServer = factory.getWebServer(new EchoHandler());
 		this.webServer.start();
 		factory.setPort(this.webServer.getPort());
-		this.thrown.expect(WebServerException.class);
+		this.thrown.expect(PortInUseException.class);
+		this.thrown.expect(
+				Matchers.hasProperty("port", Matchers.equalTo(this.webServer.getPort())));
 		factory.getWebServer(new EchoHandler()).start();
 	}