Handle scoped proxy properly in MBeanExporter

Previously, if a bean has a scoped proxy and is annotated to be exposed
to the JMX domain, both the scoped proxy and the target instance were
exposed in the JMX domain, resulting in a duplicate entries. Worse, if
such bean defines an explicit name, the application wouldn't start
because of a name conflict.

This commit deals explicitely with scoped proxy and make sure to only
expose the relevant bean.

Issue: SPR-12529

Author: snicoll

spring-aop/src/main/java/org/springframework/aop/scope/ScopedProxyUtils.java

@@ -97,4 +97,12 @@ public static String getTargetBeanName(String originalBeanName) {
 		return TARGET_NAME_PREFIX + originalBeanName;
 	}
 
+	/**
+	 * Specify if the {@code beanName} is the name of a bean that references the target
+	 * bean within a scoped proxy.
+	 */
+	public static boolean isScopedTarget(String beanName) {
+		return beanName.startsWith(TARGET_NAME_PREFIX);
+	}
+
 }

spring-context/src/main/java/org/springframework/jmx/export/MBeanExporter.java

@@ -39,6 +39,7 @@
 import javax.management.modelmbean.RequiredModelMBean;
 
 import org.springframework.aop.framework.ProxyFactory;
+import org.springframework.aop.scope.ScopedProxyUtils;
 import org.springframework.aop.support.AopUtils;
 import org.springframework.aop.target.LazyInitTargetSource;
 import org.springframework.beans.factory.BeanClassLoaderAware;
@@ -891,8 +892,9 @@ private void autodetect(AutodetectCallback callback) {
 					if (beanClass != null && callback.include(beanClass, beanName)) {
 						boolean lazyInit = isBeanDefinitionLazyInit(this.beanFactory, beanName);
 						Object beanInstance = (!lazyInit ? this.beanFactory.getBean(beanName) : null);
-						if (!this.beans.containsValue(beanName) && (beanInstance == null ||
-								!CollectionUtils.containsInstance(this.beans.values(), beanInstance))) {
+						if (!ScopedProxyUtils.isScopedTarget(beanName) && !this.beans.containsValue(beanName) &&
+								(beanInstance == null ||
+										!CollectionUtils.containsInstance(this.beans.values(), beanInstance))) {
 							// Not already registered for JMX exposure.
 							this.beans.put(beanName, (beanInstance != null ? beanInstance : beanName));
 							if (logger.isInfoEnabled()) {

spring-context/src/test/java/org/springframework/jmx/export/annotation/EnableMBeanExportConfigurationTests.java

@@ -29,6 +29,8 @@
 import org.springframework.context.annotation.EnableMBeanExport;
 import org.springframework.context.annotation.Lazy;
 import org.springframework.context.annotation.MBeanExportConfiguration;
+import org.springframework.context.annotation.Scope;
+import org.springframework.context.annotation.ScopedProxyMode;
 import org.springframework.jmx.export.MBeanExporterTests;
 import org.springframework.jmx.export.TestDynamicMBean;
 import org.springframework.jmx.support.MBeanServerFactoryBean;
@@ -62,6 +64,20 @@ public void testLazyNaming() throws Exception {
 		}
 	}
 
+	@Test
+	public void testOnlyTargetClassIsExposed() throws Exception {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(
+				ProxyConfiguration.class);
+		try {
+			MBeanServer server = (MBeanServer) ctx.getBean("server");
+			ObjectName oname = ObjectNameManager.getInstance("bean:name=testBean4");
+			assertNotNull(server.getObjectInstance(oname));
+			assertEquals("TEST", server.getAttribute(oname, "Name"));
+		} finally {
+			ctx.close();
+		}
+	}
+
 	@Test
 	public void testPlaceholderBased() throws Exception {
 		MockEnvironment env = new MockEnvironment();
@@ -151,6 +167,26 @@ public AnnotationTestBean testBean() {
 		}
 	}
 
+	@Configuration
+	@EnableMBeanExport(server = "server")
+	static class ProxyConfiguration {
+
+		@Bean
+		public MBeanServerFactoryBean server() throws Exception {
+			return new MBeanServerFactoryBean();
+		}
+
+		@Bean
+		@Lazy
+		@Scope(proxyMode = ScopedProxyMode.TARGET_CLASS)
+		public AnnotationTestBean testBean() {
+			AnnotationTestBean bean = new AnnotationTestBean();
+			bean.setName("TEST");
+			bean.setAge(100);
+			return bean;
+		}
+	}
+
 
 	@Configuration
 	@EnableMBeanExport(server = "${serverName}")