Polish "Return -1 port for non-listening WebServers"

See gh-24606

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/jetty/JettyWebServer.java

 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 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.
@@ -207,18 +207,6 @@ public class JettyWebServer implements WebServer {
 		return ports.toString();
 	}
 
-	private Integer getLocalPort(Connector connector) {
-		try {
-			// Jetty 9 internals are different, but the method name is the same
-			return (Integer) ReflectionUtils
-					.invokeMethod(ReflectionUtils.findMethod(connector.getClass(), "getLocalPort"), connector);
-		}
-		catch (Exception ex) {
-			logger.info("could not determine port ( " + ex.getMessage() + ")");
-			return 0;
-		}
-	}
-
 	private String getProtocols(Connector connector) {
 		List<String> protocols = connector.getProtocols();
 		return " (" + StringUtils.collectionToDelimitedString(protocols, ", ") + ")";
@@ -275,13 +263,32 @@ public class JettyWebServer implements WebServer {
 	@Override
 	public int getPort() {
 		Connector[] connectors = this.server.getConnectors();
-		Integer localPort = -1;
 		for (Connector connector : connectors) {
-			// Probably only one...
-			localPort = getLocalPort(connector);
-			break;
+			Integer localPort = getLocalPort(connector);
+			if (localPort != null && localPort > 0) {
+				return localPort;
 			}
-		return (localPort > 0) ? localPort : -1;
+		}
+		return -1;
+	}
+
+	private Integer getLocalPort(Connector connector) {
+		try {
+			if (connector instanceof NetworkConnector) {
+				return ((NetworkConnector) connector).getLocalPort();
+			}
+		}
+		catch (Exception ex) {
+		}
+		try {
+			// Jetty 9 internals are different, but the method name is the same
+			return (Integer) ReflectionUtils
+					.invokeMethod(ReflectionUtils.findMethod(connector.getClass(), "getLocalPort"), connector);
+		}
+		catch (Exception ex) {
+			logger.info("could not determine port ( " + ex.getMessage() + ")");
+		}
+		return 0;
 	}
 
 	@Override

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

 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 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-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/tomcat/TomcatWebServer.java

 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 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-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowWebServer.java

 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 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-project/spring-boot/src/test/java/org/springframework/boot/web/reactive/server/AbstractReactiveWebServerFactoryTests.java

 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 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-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/server/AbstractServletWebServerFactoryTests.java

 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 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.