javax.slee.management.ServiceStateChangeNotification Maven / Gradle / Ivy
package javax.slee.management;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import javax.management.Notification;
import javax.slee.ServiceID;
/**
* This notification is emitted by a {@link ServiceManagementMBean} object to
* indicate a change in the operational state of a Service.
*
* The notification type of Service state change notifications is specified by the
* {@link ServiceManagementMBean#SERVICE_STATE_CHANGE_NOTIFICATION_TYPE} attribute.
* @since SLEE 1.1
*/
public final class ServiceStateChangeNotification extends Notification implements VendorExtensions {
/**
* Create a ServiceStateChangeNotification to notify listeners of a
* change in the operational state of a Service. Notifications are broadcast
* after the Service has changed to the new state.
* @param serviceManagementMBean the ServiceManagementMBean object that is
* emitting this notification.
* @param service the component identifier of the Service that has changed state.
* @param newState the new operational state of the Service.
* @param oldState the old operational state of the Service.
* @param sequenceNumber the notification sequence number within the source
* ServiceManagementMBean object.
* @throws NullPointerException if notificationSource, service,
* newState, or oldState is null.
*/
public ServiceStateChangeNotification(ServiceManagementMBean serviceManagementMBean, ServiceID service, ServiceState newState, ServiceState oldState, long sequenceNumber) throws NullPointerException {
super(ServiceManagementMBean.SERVICE_STATE_CHANGE_NOTIFICATION_TYPE, serviceManagementMBean, sequenceNumber, System.currentTimeMillis(),
service + " state changed from " + oldState + " to " + newState
);
if (serviceManagementMBean == null) throw new NullPointerException("serviceManagementMBean is null");
if (service == null) throw new NullPointerException("service is null");
if (newState == null) throw new NullPointerException("newState is null");
if (oldState == null) throw new NullPointerException("oldState is null");
this.service = service;
this.newState = newState;
this.oldState = oldState;
}
/**
* Get the component identifier of the Service that has changed state.
* @return the Service component identifier.
*/
public ServiceID getService() {
return service;
}
/**
* Get the new operational state of the Service.
* @return the new state.
*/
public ServiceState getNewState() {
return newState;
}
/**
* Get the state the Service was in before the change to the new state.
* @return the old state.
*/
public ServiceState getOldState() {
return oldState;
}
/**
* Enable the serialization of vendor-specific data for objects of this class.
* This method is typically used by a SLEE implementation that wants to export
* vendor-specific data with objects of this class to management clients.
*
* By default, any vendor-specific data included in an object of this class will
* not be included in the serialization stream when the object is serialized.
* Invoking this method changes this behavior so that vendor-specific data is
* included in the serialization stream when an object of this class is serialized.
*
* This method should only be invoked if the vendor-specific data is serializable
* via standard Java serialization means.
* @see #disableVendorDataSerialization
* @see #setVendorData
*/
public static void enableVendorDataSerialization() {
vendorDataSerializationEnabled = true;
}
/**
* Disable the serialization of vendor-specific data for objects of this class.
*
* If the serialization of vendor-specific data for objects of this class has
* been enabled via the {@link #enableVendorDataSerialization} method, this
* method disables that behavior again.
*/
public static void disableVendorDataSerialization() {
vendorDataSerializationEnabled = false;
}
/**
* Enable the deserialization of vendor-specific data for objects of this class.
* This method is typically used by a management client that wants to obtain any
* vendor-specific data included in the serialization stream of objects of this
* class.
*
* By default, any vendor-specific data included in the serialization stream of
* objects of this class is discarded upon deserialization. Invoking this method
* changes that behavior so that the vendor-specific data is also deserialized
* when an object of this class is deserialized. A management client that enables
* the deserialization of vendor-specific data must ensure that any necessary
* classes required to deserialize that data is available in the relevant
* classloader.
* @see #disableVendorDataDeserialization
* @see #getVendorData
*/
public static void enableVendorDataDeserialization() {
vendorDataDeserializationEnabled = true;
}
/**
* Disable the deserialization of vendor-specific data for objects of this class.
*
* If the deserialization of vendor-specific data for objects of this class has
* been enabled via the {@link #enableVendorDataDeserialization} method, this
* method disables that behavior again.
*/
public static void disableVendorDataDeserialization() {
vendorDataDeserializationEnabled = false;
}
/**
* Set the vendor-specific data.
* @param vendorData the vendor-specific data.
*/
public void setVendorData(Object vendorData) {
this.vendorData = vendorData;
}
/**
* Get the vendor-specific data.
* @return the vendor-specific data.
*/
public Object getVendorData() {
return vendorData;
}
/**
* Get a string representation for this notification.
* @return a string representation for this notification.
*/
public String toString() {
StringBuffer buf = new StringBuffer();
buf.append("ServiceStateChangeNotification[timestamp=")
.append(getTimeStamp())
.append(",service=")
.append(service)
.append(",old state=")
.append(oldState)
.append(",new state=")
.append(newState);
if (vendorData != null) buf.append(",vendor data=").append(vendorData);
buf.append("]");
return buf.toString();
}
// special handling of serialization
private void writeObject(ObjectOutputStream out) throws IOException {
VendorExtensionUtils.writeObject(out, vendorDataSerializationEnabled ? vendorData : null);
}
// special handling of deserialization
private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
vendorData = VendorExtensionUtils.readObject(in, vendorDataDeserializationEnabled);
}
private final ServiceID service;
private final ServiceState newState;
private final ServiceState oldState;
private static volatile boolean vendorDataSerializationEnabled = false;
private static volatile boolean vendorDataDeserializationEnabled = false;
private transient Object vendorData;
}