Spring's JMX support can rely on native MXBean detection on Java 6+

Issue: SPR-12574
(cherry picked from commit 0919a15)

Author: jhoeller

spring-context/src/main/java/org/springframework/jmx/access/MBeanClientInterceptor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2014 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.
@@ -263,20 +263,13 @@ public void prepare() {
 			}
 			this.invocationHandler = null;
 			if (this.useStrictCasing) {
-				// Use the JDK's own MBeanServerInvocationHandler,
-				// in particular for native MXBean support on Java 6.
-				if (JmxUtils.isMXBeanSupportAvailable()) {
-					this.invocationHandler =
-							new MBeanServerInvocationHandler(this.serverToUse, this.objectName,
-									(this.managementInterface != null && JMX.isMXBeanInterface(this.managementInterface)));
-				}
-				else {
-					this.invocationHandler = new MBeanServerInvocationHandler(this.serverToUse, this.objectName);
-				}
+				// Use the JDK's own MBeanServerInvocationHandler, in particular for native MXBean support.
+				this.invocationHandler = new MBeanServerInvocationHandler(this.serverToUse, this.objectName,
+						(this.managementInterface != null && JMX.isMXBeanInterface(this.managementInterface)));
 			}
 			else {
-				// Non-strict casing can only be achieved through custom
-				// invocation handling. Only partial MXBean support available!
+				// Non-strict casing can only be achieved through custom invocation handling.
+				// Only partial MXBean support available!
 				retrieveMBeanInfo();
 			}
 		}

spring-context/src/main/java/org/springframework/jmx/support/JmxUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2014 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.
@@ -22,10 +22,10 @@
 import java.util.Hashtable;
 import java.util.List;
 import javax.management.DynamicMBean;
+import javax.management.JMX;
 import javax.management.MBeanParameterInfo;
 import javax.management.MBeanServer;
 import javax.management.MBeanServerFactory;
-import javax.management.MXBean;
 import javax.management.MalformedObjectNameException;
 import javax.management.ObjectName;
 
@@ -59,16 +59,6 @@ public abstract class JmxUtils {
 	 */
 	private static final String MBEAN_SUFFIX = "MBean";
 
-	/**
-	 * Suffix used to identify a Java 6 MXBean interface.
-	 */
-	private static final String MXBEAN_SUFFIX = "MXBean";
-
-	private static final String MXBEAN_ANNOTATION_CLASS_NAME = "javax.management.MXBean";
-
-
-	private static final boolean mxBeanAnnotationAvailable =
-			ClassUtils.isPresent(MXBEAN_ANNOTATION_CLASS_NAME, JmxUtils.class.getClassLoader());
 
 	private static final Log logger = LogFactory.getLog(JmxUtils.class);
 
@@ -304,14 +294,7 @@ public static Class<?> getMXBeanInterface(Class<?> clazz) {
 		}
 		Class<?>[] implementedInterfaces = clazz.getInterfaces();
 		for (Class<?> iface : implementedInterfaces) {
-			boolean isMxBean = iface.getName().endsWith(MXBEAN_SUFFIX);
-			if (mxBeanAnnotationAvailable) {
-				Boolean checkResult = MXBeanChecker.evaluateMXBeanAnnotation(iface);
-				if (checkResult != null) {
-					isMxBean = checkResult;
-				}
-			}
-			if (isMxBean) {
+			if (JMX.isMXBeanInterface(iface)) {
 				return iface;
 			}
 		}
@@ -322,21 +305,11 @@ public static Class<?> getMXBeanInterface(Class<?> clazz) {
 	 * Check whether MXBean support is available, i.e. whether we're running
 	 * on Java 6 or above.
 	 * @return {@code true} if available; {@code false} otherwise
+	 * @deprecated as of Spring 4.0, since Java 6 is required anyway now
 	 */
+	@Deprecated
 	public static boolean isMXBeanSupportAvailable() {
-		return mxBeanAnnotationAvailable;
-	}
-
-
-	/**
-	 * Inner class to avoid a Java 6 dependency.
-	 */
-	private static class MXBeanChecker {
-
-		public static Boolean evaluateMXBeanAnnotation(Class<?> iface) {
-			MXBean mxBean = iface.getAnnotation(MXBean.class);
-			return (mxBean != null ? mxBean.value() : null);
-		}
+		return true;
 	}
 
 }