[bs-78] Add port=0 option to switch off main servlet container

[Fixes #48888639]

spring-bootstrap/src/main/java/org/springframework/bootstrap/context/embedded/AbstractEmbeddedServletContainerFactory.java

@@ -114,11 +114,12 @@ public abstract class AbstractEmbeddedServletContainerFactory implements
 
 	/**
 	 * Sets the port that the embedded servlet container should listen on. If not
-	 * specified port '8080' will be used.
+	 * specified port '8080' will be used. Use port 0 to switch off the server completely.
+	 * 
 	 * @param port the port to set
 	 */
 	public void setPort(int port) {
-		if (port < 1 || port > 65535) {
+		if (port < 0 || port > 65535) {
 			throw new IllegalArgumentException("Port must be between 1 and 65535");
 		}
 		this.port = port;

spring-bootstrap/src/main/java/org/springframework/bootstrap/context/embedded/EmptyEmbeddedServletContainer.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2012-2013 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.bootstrap.context.embedded;
+
+/**
+ * @author Dave Syer
+ * 
+ */
+public class EmptyEmbeddedServletContainer implements EmbeddedServletContainer {
+
+	@Override
+	public void stop() throws EmbeddedServletContainerException {
+		// do nothing
+	}
+
+}

spring-bootstrap/src/main/java/org/springframework/bootstrap/context/embedded/jetty/JettyEmbeddedServletContainerFactory.java

@@ -32,7 +32,9 @@ import org.eclipse.jetty.webapp.AbstractConfiguration;
 import org.eclipse.jetty.webapp.Configuration;
 import org.eclipse.jetty.webapp.WebAppContext;
 import org.springframework.bootstrap.context.embedded.AbstractEmbeddedServletContainerFactory;
+import org.springframework.bootstrap.context.embedded.EmbeddedServletContainer;
 import org.springframework.bootstrap.context.embedded.EmbeddedServletContainerFactory;
+import org.springframework.bootstrap.context.embedded.EmptyEmbeddedServletContainer;
 import org.springframework.bootstrap.context.embedded.ErrorPage;
 import org.springframework.context.ResourceLoaderAware;
 import org.springframework.core.io.ResourceLoader;
@@ -91,8 +93,11 @@ public class JettyEmbeddedServletContainerFactory extends
 	}
 
 	@Override
-	public JettyEmbeddedServletContainer getEmbdeddedServletContainer(
+	public EmbeddedServletContainer getEmbdeddedServletContainer(
 			ServletContextInitializer... initializers) {
+		if (getPort() == 0) {
+			return new EmptyEmbeddedServletContainer();
+		}
 		Server server = new Server(getPort());
 
 		WebAppContext context = new WebAppContext();

spring-bootstrap/src/main/java/org/springframework/bootstrap/context/embedded/tomcat/TomcatEmbeddedServletContainerFactory.java

@@ -40,6 +40,7 @@ import org.springframework.bootstrap.context.embedded.AbstractEmbeddedServletCon
 import org.springframework.bootstrap.context.embedded.EmbeddedServletContainer;
 import org.springframework.bootstrap.context.embedded.EmbeddedServletContainerException;
 import org.springframework.bootstrap.context.embedded.EmbeddedServletContainerFactory;
+import org.springframework.bootstrap.context.embedded.EmptyEmbeddedServletContainer;
 import org.springframework.bootstrap.context.embedded.ErrorPage;
 import org.springframework.context.ResourceLoaderAware;
 import org.springframework.core.io.ResourceLoader;
@@ -107,6 +108,9 @@ public class TomcatEmbeddedServletContainerFactory extends
 	@Override
 	public EmbeddedServletContainer getEmbdeddedServletContainer(
 			ServletContextInitializer... initializers) {
+		if (getPort() == 0) {
+			return new EmptyEmbeddedServletContainer();
+		}
 		File baseDir = (this.baseDirectory != null ? this.baseDirectory
 				: createTempDir("tomcat"));
 		this.tomcat.setBaseDir(baseDir.getAbsolutePath());
@@ -330,6 +334,9 @@ public class TomcatEmbeddedServletContainerFactory extends
 			public EmbeddedServletContainer getEmbdeddedServletContainer(
 					ServletContextInitializer... initializers) {
 
+				if (getPort() == 0) {
+					return new EmptyEmbeddedServletContainer();
+				}
 				StandardService service = new StandardService();
 				service.setName(name);
 				Connector connector = new Connector("HTTP/1.1");

spring-bootstrap/src/test/java/org/springframework/bootstrap/context/embedded/AbstractEmbeddedServletContainerFactoryTests.java

@@ -38,10 +38,6 @@ import org.junit.Test;
 import org.junit.rules.ExpectedException;
 import org.junit.rules.TemporaryFolder;
 import org.mockito.InOrder;
-import org.springframework.bootstrap.context.embedded.AbstractEmbeddedServletContainerFactory;
-import org.springframework.bootstrap.context.embedded.EmbeddedServletContainer;
-import org.springframework.bootstrap.context.embedded.FilterRegistrationBean;
-import org.springframework.bootstrap.context.embedded.ServletRegistrationBean;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.client.ClientHttpRequest;
 import org.springframework.http.client.ClientHttpResponse;
@@ -90,6 +86,17 @@ public abstract class AbstractEmbeddedServletContainerFactoryTests {
 		assertThat(getResponse("http://localhost:8080/hello"), equalTo("Hello World"));
 	}
 
+	@Test
+	public void emptyServer() throws Exception {
+		AbstractEmbeddedServletContainerFactory factory = getFactory();
+		factory.setPort(0);
+		this.container = factory
+				.getEmbdeddedServletContainer(exampleServletRegistration());
+		this.thrown.expect(ConnectException.class);
+		this.thrown.expectMessage("Connection refused");
+		getResponse("http://localhost:8080/hello");
+	}
+
 	@Test
 	public void stopServlet() throws Exception {
 		AbstractEmbeddedServletContainerFactory factory = getFactory();