Add JMX MBean for Tomcat DataSource

If the DataSource is a Tomcat one we force it to register an MBean
if spring.jmx.enabled=true

Fixes gh-1590

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfiguration.java

@@ -16,9 +16,14 @@
 
 package org.springframework.boot.autoconfigure.jdbc;
 
+import java.sql.SQLException;
+
 import javax.sql.DataSource;
 import javax.sql.XADataSource;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.tomcat.jdbc.pool.DataSourceProxy;
 import org.springframework.beans.factory.BeanFactoryUtils;
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -27,6 +32,7 @@ import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.autoconfigure.condition.ConditionOutcome;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnExpression;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.SpringBootCondition;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceInitializerPostProcessor.Registrar;
@@ -60,6 +66,8 @@ import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseType;
 @Import({ Registrar.class, DataSourcePoolMetadataProvidersConfiguration.class })
 public class DataSourceAutoConfiguration {
 	
+	private static Log logger = LogFactory.getLog(DataSourceAutoConfiguration.class);
+
 	/**
 	 * Determines if the {@code dataSource} being used by Spring was created from
 	 * {@link EmbeddedDataSourceConfiguration}.
@@ -134,7 +142,25 @@ public class DataSourceAutoConfiguration {
 		public NamedParameterJdbcTemplate namedParameterJdbcTemplate() {
 			return new NamedParameterJdbcTemplate(this.dataSource);
 		}
+	}
 
+	@Configuration
+	@ConditionalOnExpression("${spring.datasource.jmxEnabled:true}")
+	@ConditionalOnClass(name = "org.apache.tomcat.jdbc.pool.DataSourceProxy")
+	@Conditional(DataSourceAutoConfiguration.DataSourceAvailableCondition.class)
+	protected static class TomcatDataSourceJmxConfiguration {
+		@Bean
+		public Object dataSourceMBean(DataSource dataSource) {
+			if (dataSource instanceof DataSourceProxy) {
+				try {
+					return ((DataSourceProxy) dataSource).createPool().getJmxPool();
+				}
+				catch (SQLException e) {
+					logger.warn("Cannot expose DataSource to JMX (could not connect)");
+				}
+			}
+			return null;
+		}
 	}
 
 	/**

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/TomcatDataSourceConfigurationTests.java

@@ -26,6 +26,7 @@ import org.apache.tomcat.jdbc.pool.interceptor.SlowQueryReport;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.boot.test.EnvironmentTestUtils;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
@@ -134,11 +135,20 @@ public class TomcatDataSourceConfigurationTests {
 	@Import(DataSourceAutoConfiguration.class)
 	protected static class TomcatDataSourceConfiguration {
 
+		@Autowired
+		private DataSourceProperties properties;
+
 		@Bean
 		@ConfigurationProperties(prefix = DataSourceProperties.PREFIX)
 		public DataSource dataSource() {
-			return DataSourceBuilder.create()
-					.type(org.apache.tomcat.jdbc.pool.DataSource.class).build();
+			DataSourceBuilder factory = DataSourceBuilder
+					.create(this.properties.getClassLoader())
+					.driverClassName(this.properties.getDriverClassName())
+					.url(this.properties.getUrl())
+					.username(this.properties.getUsername())
+					.password(this.properties.getPassword())
+					.type(org.apache.tomcat.jdbc.pool.DataSource.class);
+			return factory.build();
 		}
 
 	}

spring-boot-samples/spring-boot-sample-data-jpa/src/test/java/sample/data/jpa/SampleDataJpaApplicationTests.java

 package sample.data.jpa;
 
+import static org.junit.Assert.assertEquals;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import java.lang.management.ManagementFactory;
+
+import javax.management.ObjectName;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.SpringApplicationConfiguration;
 import org.springframework.test.context.ActiveProfiles;
+import org.springframework.test.context.TestPropertySource;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.test.context.web.WebAppConfiguration;
 import org.springframework.test.web.servlet.MockMvc;
 import org.springframework.test.web.servlet.setup.MockMvcBuilders;
 import org.springframework.web.context.WebApplicationContext;
 
-import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
-
 /**
  * Integration test to run the application.
  *
  * @author Oliver Gierke
+ * @author Dave Syer
  */
 @RunWith(SpringJUnit4ClassRunner.class)
 @SpringApplicationConfiguration(classes = SampleDataJpaApplication.class)
 @WebAppConfiguration
+// Enable JMX so we can test the MBeans (you can't do this in a properties file)
+@TestPropertySource(properties="spring.jmx.enabled:true")
 @ActiveProfiles("scratch")
 // Separate profile for web tests to avoid clashing databases
 public class SampleDataJpaApplicationTests {
@@ -44,4 +53,11 @@ public class SampleDataJpaApplicationTests {
 		this.mvc.perform(get("/")).andExpect(status().isOk())
 				.andExpect(content().string("Bath"));
 	}
+
+	@Test
+	public void testJmx() throws Exception {
+		assertEquals(1, ManagementFactory.getPlatformMBeanServer().queryMBeans(
+				new ObjectName("jpa.sample:type=ConnectionPool,*"), null).size());
+	}
+
 }

spring-boot-samples/spring-boot-sample-data-jpa/src/test/resources/application-scratch.properties

 spring.datasource.url: jdbc:hsqldb:mem:scratchdb
+spring.jmx.default_domain: jpa.sample
\ No newline at end of file