Chapter 13: Using Systems Management

Creating service MBeans

Service MBeans must expose a well-defined life-cycle API that provides the ability to start, stop, and check the status of managed services. You can create service MBeans either by writing your own service MBean class, or by extending the ServiceSupport class, which is provided with this release.

Because MBeans are invoked via the JMX MBeanServer APIs, service MBeans are not required to implement a particular interface or extend a particular class to ensure life-cycle compliancy. However, they are required to implement the methods described in Table 13-3.

**Table 13-3: MBean required methods**
Method	Description
void start()	Starts the MBean
void stop()	Stops the MBean
int getState()	Returns the state of the MBean. The return values, as defined in JSR 77, can be: 0 – STARTING 1 – RUNNING 2 – STOPPING 4 – FAILED

The com.sybase.management.jmx.services.ServiceSupport class is available to extend, if required. This class provides all the API methods described in Table 13-3 and Table 13-4. If you extend this class, you can override the methods defined in Table 13-4, and let the ServiceSupport class handle state management for you. See “Service builder” for an example of how to do this. The ServiceSupport class provides default implementations for all the methods listed in Table 13-4, so you can implement only the ones you need. The ServiceSupport class is in ROOT/lib/sybasejmx.jar.

**Table 13-4: MBean optional methods**
Method	Description
void getLogfile()	Gets the service’s log file
void initService()	Initializes the resources
void refreshService()	Refreshes the MBean without restarting
void restartService()	Stops, then restarts the MBean
void startRecursiveService()	Starts dependent MBeans
void startService()	Starts the service
void stopService()	Stops the service
void terminateService()	Cleans up the resources

Creating MBean and service XML definitions

View this book as PDF