Use '-1' to disable management port

Update `EndpointWebMvcAutoConfiguration` to use '-1' to indicate that
the management context should be disabled. This brings consistency
between the server settings and the management settings and allows '0'
to be used to pick a random port.

Fixed gh-311

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/EndpointWebMvcAutoConfigurationTests.java

@@ -33,7 +33,11 @@ import org.springframework.boot.autoconfigure.web.HttpMessageConvertersAutoConfi
 import org.springframework.boot.autoconfigure.web.ServerPropertiesAutoConfiguration;
 import org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration;
 import org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext;
+import org.springframework.boot.context.embedded.EmbeddedServletContainer;
+import org.springframework.boot.context.embedded.EmbeddedServletContainerInitializedEvent;
 import org.springframework.boot.test.EnvironmentTestUtils;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationListener;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.http.HttpMethod;
@@ -46,6 +50,7 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.ResponseBody;
 
 import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.not;
 import static org.junit.Assert.assertThat;
 
 /**
@@ -101,6 +106,27 @@ public class EndpointWebMvcAutoConfigurationTests {
 		assertAllClosed();
 	}
 
+	@Test
+	public void onRandomPort() throws Exception {
+		this.applicationContext.register(RootConfig.class, RandomPortConfig.class,
+				PropertyPlaceholderAutoConfiguration.class,
+				EmbeddedServletContainerAutoConfiguration.class,
+				HttpMessageConvertersAutoConfiguration.class,
+				DispatcherServletAutoConfiguration.class, WebMvcAutoConfiguration.class,
+				ManagementServerPropertiesAutoConfiguration.class,
+				EndpointWebMvcAutoConfiguration.class, ErrorMvcAutoConfiguration.class);
+		GrabManagementPort grabManagementPort = new GrabManagementPort(
+				this.applicationContext);
+		this.applicationContext.addApplicationListener(grabManagementPort);
+		this.applicationContext.refresh();
+		int managementPort = grabManagementPort.getServletContainer().getPort();
+		assertThat(managementPort, not(equalTo(8080)));
+		assertContent("/controller", 8080, "controlleroutput");
+		assertContent("/endpoint", 8080, null);
+		assertContent("/controller", managementPort, null);
+		assertContent("/endpoint", managementPort, "endpointoutput");
+	}
+
 	@Test
 	public void disabled() throws Exception {
 		this.applicationContext.register(RootConfig.class, DisableConfig.class,
@@ -230,7 +256,7 @@ public class EndpointWebMvcAutoConfigurationTests {
 	}
 
 	@Configuration
-	public static class DisableConfig {
+	public static class RandomPortConfig {
 
 		@Bean
 		public ManagementServerProperties managementServerProperties() {
@@ -241,6 +267,18 @@ public class EndpointWebMvcAutoConfigurationTests {
 
 	}
 
+	@Configuration
+	public static class DisableConfig {
+
+		@Bean
+		public ManagementServerProperties managementServerProperties() {
+			ManagementServerProperties properties = new ManagementServerProperties();
+			properties.setPort(-1);
+			return properties;
+		}
+
+	}
+
 	public static class TestEndpoint implements MvcEndpoint {
 
 		@RequestMapping
@@ -267,4 +305,27 @@ public class EndpointWebMvcAutoConfigurationTests {
 
 	}
 
+	private static class GrabManagementPort implements
+			ApplicationListener<EmbeddedServletContainerInitializedEvent> {
+
+		private ApplicationContext rootContext;
+
+		private EmbeddedServletContainer servletContainer;
+
+		public GrabManagementPort(ApplicationContext rootContext) {
+			this.rootContext = rootContext;
+		}
+
+		@Override
+		public void onApplicationEvent(EmbeddedServletContainerInitializedEvent event) {
+			if (event.getApplicationContext() != this.rootContext) {
+				this.servletContainer = event.getEmbeddedServletContainer();
+			}
+		}
+
+		public EmbeddedServletContainer getServletContainer() {
+			return this.servletContainer;
+		}
+	}
+
 }