/**
* This util class provides a method to register an MBean using
* our standard naming convention as described in the doc
* for {link {@link #register(String, String, Object)}
*/
@InterfaceAudience.Public
@InterfaceStability.Stable
public class MBeans {
private static final Log LOG = LogFactory.getLog(MBeans.class);
/**
* Register the MBean using our standard MBeanName format
* "hadoop:service=<serviceName>,name=<nameName>"
* Where the <serviceName> and <nameName> are the supplied parameters
*
* @param serviceName
* @param nameName
* @param theMbean - the MBean to register
* @return the named used to register the MBean
*/
static public ObjectName register(String serviceName, String nameName,
Object theMbean) {
final MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
ObjectName name = getMBeanName(serviceName, nameName);
try {
mbs.registerMBean(theMbean, name);
LOG.debug("Registered "+ name);
return name;
} catch (InstanceAlreadyExistsException iaee) {
if (LOG.isTraceEnabled()) {
LOG.trace("Failed to register MBean \""+ name + "\"", iaee);
} else {
LOG.warn("Failed to register MBean \""+ name
+ "\": Instance already exists.");
}
} catch (Exception e) {
LOG.warn("Failed to register MBean \""+ name + "\"", e);
}
return null;
}
static public void unregister(ObjectName mbeanName) {
LOG.debug("Unregistering "+ mbeanName);
final MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
if (mbeanName == null) {
LOG.debug("Stacktrace: ", new Throwable());
return;
}
try {
mbs.unregisterMBean(mbeanName);
} catch (Exception e) {
LOG.warn("Error unregistering "+ mbeanName, e);
}
DefaultMetricsSystem.removeMBeanName(mbeanName);
}
static private ObjectName getMBeanName(String serviceName, String nameName) {
ObjectName name = null;
String nameStr = "Hadoop:service="+ serviceName +",name="+ nameName;
try {
name = DefaultMetricsSystem.newMBeanName(nameStr);
} catch (Exception e) {
LOG.warn("Error creating MBean object name: "+ nameStr, e);
}
return name;
}
}