Disable jmx by default

Change JmxAutoConfiguration so that by default JMX exposure is not
enabled. This matches the Javdoc text.

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jmx/JmxAutoConfiguration.java

@@ -36,7 +36,7 @@ import org.springframework.jmx.export.MBeanExporter;
 @Configuration
 @ConditionalOnClass({ MBeanExporter.class })
 @ConditionalOnMissingBean({ MBeanExporter.class })
-@ConditionalOnExpression("${spring.jmx.enabled:true}")
+@ConditionalOnExpression("${spring.jmx.enabled:false}")
 public class JmxAutoConfiguration {
 
 	@Configuration

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jmx/JmxAutoConfigurationTests.java

@@ -17,7 +17,9 @@
 package org.springframework.boot.autoconfigure.jmx;
 
 import org.junit.After;
+import org.junit.Rule;
 import org.junit.Test;
+import org.junit.rules.ExpectedException;
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Bean;
@@ -37,6 +39,9 @@ import static org.junit.Assert.assertNotNull;
  */
 public class JmxAutoConfigurationTests {
 
+	@Rule
+	public ExpectedException thrown = ExpectedException.none();
+
 	private AnnotationConfigApplicationContext context;
 
 	@After
@@ -51,6 +56,18 @@ public class JmxAutoConfigurationTests {
 		this.context = new AnnotationConfigApplicationContext();
 		this.context.register(JmxAutoConfiguration.class);
 		this.context.refresh();
+		this.thrown.expect(NoSuchBeanDefinitionException.class);
+		this.context.getBean(MBeanExporter.class);
+	}
+
+	@Test
+	public void testEnabledMBeanExport() {
+		MockEnvironment env = new MockEnvironment();
+		env.setProperty("spring.jmx.enabled", "true");
+		this.context = new AnnotationConfigApplicationContext();
+		this.context.setEnvironment(env);
+		this.context.register(JmxAutoConfiguration.class);
+		this.context.refresh();
 
 		assertNotNull(this.context.getBean(MBeanExporter.class));
 	}

spring-boot-samples/spring-boot-sample-actuator/src/main/resources/application.properties

@@ -15,3 +15,5 @@ shell.auth: spring
 #shell.auth: key
 #shell.auth.key.path: ${user.home}/test/id_rsa.pub.pem
 #shell.auth: simple
+spring.jmx.enabled: true
+