| /** |
| * |
| * Copyright 2005 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. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.gbean.kernel; |
| |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.Iterator; |
| import java.util.LinkedHashMap; |
| import java.util.LinkedHashSet; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| |
| /** |
| * The ServiceMonitorBroadcaster broadcasts kernel events to registered service monitors. |
| * |
| * @author Dain Sundstrom |
| * @version $Id$ |
| * @since 1.0 |
| */ |
| public class ServiceMonitorBroadcaster implements ServiceMonitor { |
| /** |
| * The monitors for service events. |
| */ |
| private final Map serviceMonitors = new LinkedHashMap(); |
| |
| /** |
| * The monitor we notify when we get an exception from a service monitor. |
| */ |
| private final KernelMonitor kernelMonitor; |
| |
| /** |
| * Creates a ServiceMonitorBroadcaster that notifies the specified kernel monitor when an error occurs while |
| * notifying the registered service monitors. |
| * |
| * @param kernelMonitor the monitor to notify when an error occurs while notifying the registered service monitors |
| */ |
| public ServiceMonitorBroadcaster(KernelMonitor kernelMonitor) { |
| this.kernelMonitor = kernelMonitor; |
| } |
| |
| /** |
| * Adds a service monitor for a specific service, or if the specified service name is null, a global monitor. |
| * <p/> |
| * Note: the order in which service monitors are notified is not specified. |
| * |
| * @param serviceMonitor the service monitor to add |
| * @param serviceName the unique name of the service to monitor or null to monitor all services |
| */ |
| public void addServiceMonitor(ServiceMonitor serviceMonitor, ServiceName serviceName) { |
| synchronized (serviceMonitors) { |
| Set monitors = (Set) serviceMonitors.get(serviceName); |
| if (monitors == null) { |
| monitors = new LinkedHashSet(); |
| serviceMonitors.put(serviceName, monitors); |
| } |
| monitors.add(serviceMonitor); |
| } |
| } |
| |
| /** |
| * Removes a service monitor. |
| * |
| * @param serviceMonitor the service monitor to remove |
| */ |
| public void removeServiceMonitor(ServiceMonitor serviceMonitor) { |
| synchronized (serviceMonitors) { |
| for (Iterator iterator = serviceMonitors.values().iterator(); iterator.hasNext();) { |
| Set monitors = (Set) iterator.next(); |
| monitors.remove(serviceMonitor); |
| if (monitors.isEmpty()) { |
| iterator.remove(); |
| } |
| } |
| } |
| } |
| |
| /** |
| * Gets the service monitors registered to recieve events for the specified service. This will include all global |
| * monitors and service specific monitors. |
| * |
| * @param serviceName the name of the service |
| * @return the monitors registerd to recieve events for the specified service |
| */ |
| private Set getServiceMonitors(ServiceName serviceName) { |
| synchronized (serviceMonitors) { |
| Set monitors = new LinkedHashSet(); |
| Set globalMonitors = (Set) serviceMonitors.get(null); |
| if (globalMonitors != null) { |
| monitors.addAll(globalMonitors); |
| } |
| Set specificMonitors = (Set) serviceMonitors.get(serviceName); |
| if (specificMonitors != null) { |
| monitors.addAll(specificMonitors); |
| } |
| return monitors; |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void serviceRegistered(ServiceEvent serviceEvent) { |
| List errors = new ArrayList(); |
| Set serviceMonitors = getServiceMonitors(serviceEvent.getServiceName()); |
| for (Iterator iterator = serviceMonitors.iterator(); iterator.hasNext();) { |
| ServiceMonitor serviceMonitor = (ServiceMonitor) iterator.next(); |
| try { |
| serviceMonitor.serviceRegistered(serviceEvent); |
| } catch (Throwable e) { |
| errors.addAll(fireServiceNotificationError(serviceMonitor, serviceEvent, e)); |
| } |
| } |
| if (!errors.isEmpty()) { |
| throw new KernelErrorsError(errors); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void serviceStarting(ServiceEvent serviceEvent) { |
| List errors = new ArrayList(); |
| Set serviceMonitors = getServiceMonitors(serviceEvent.getServiceName()); |
| for (Iterator iterator = serviceMonitors.iterator(); iterator.hasNext();) { |
| ServiceMonitor serviceMonitor = (ServiceMonitor) iterator.next(); |
| try { |
| serviceMonitor.serviceStarting(serviceEvent); |
| } catch (Throwable e) { |
| errors.addAll(fireServiceNotificationError(serviceMonitor, serviceEvent, e)); |
| } |
| } |
| if (!errors.isEmpty()) { |
| throw new KernelErrorsError(errors); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void serviceWaitingToStart(ServiceEvent serviceEvent) { |
| List errors = new ArrayList(); |
| Set serviceMonitors = getServiceMonitors(serviceEvent.getServiceName()); |
| for (Iterator iterator = serviceMonitors.iterator(); iterator.hasNext();) { |
| ServiceMonitor serviceMonitor = (ServiceMonitor) iterator.next(); |
| try { |
| serviceMonitor.serviceWaitingToStart(serviceEvent); |
| } catch (Throwable e) { |
| errors.addAll(fireServiceNotificationError(serviceMonitor, serviceEvent, e)); |
| } |
| } |
| if (!errors.isEmpty()) { |
| throw new KernelErrorsError(errors); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void serviceStartError(ServiceEvent serviceEvent) { |
| List errors = new ArrayList(); |
| Set serviceMonitors = getServiceMonitors(serviceEvent.getServiceName()); |
| for (Iterator iterator = serviceMonitors.iterator(); iterator.hasNext();) { |
| ServiceMonitor serviceMonitor = (ServiceMonitor) iterator.next(); |
| try { |
| serviceMonitor.serviceStartError(serviceEvent); |
| } catch (Throwable e) { |
| errors.addAll(fireServiceNotificationError(serviceMonitor, serviceEvent, e)); |
| } |
| } |
| if (!errors.isEmpty()) { |
| throw new KernelErrorsError(errors); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void serviceRunning(ServiceEvent serviceEvent) { |
| List errors = new ArrayList(); |
| Set serviceMonitors = getServiceMonitors(serviceEvent.getServiceName()); |
| for (Iterator iterator = serviceMonitors.iterator(); iterator.hasNext();) { |
| ServiceMonitor serviceMonitor = (ServiceMonitor) iterator.next(); |
| try { |
| serviceMonitor.serviceRunning(serviceEvent); |
| } catch (Throwable e) { |
| errors.addAll(fireServiceNotificationError(serviceMonitor, serviceEvent, e)); |
| } |
| } |
| if (!errors.isEmpty()) { |
| throw new KernelErrorsError(errors); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void serviceStopping(ServiceEvent serviceEvent) { |
| List errors = new ArrayList(); |
| Set serviceMonitors = getServiceMonitors(serviceEvent.getServiceName()); |
| for (Iterator iterator = serviceMonitors.iterator(); iterator.hasNext();) { |
| ServiceMonitor serviceMonitor = (ServiceMonitor) iterator.next(); |
| try { |
| serviceMonitor.serviceStopping(serviceEvent); |
| } catch (Throwable e) { |
| errors.addAll(fireServiceNotificationError(serviceMonitor, serviceEvent, e)); |
| } |
| } |
| if (!errors.isEmpty()) { |
| throw new KernelErrorsError(errors); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void serviceWaitingToStop(ServiceEvent serviceEvent) { |
| List errors = new ArrayList(); |
| Set serviceMonitors = getServiceMonitors(serviceEvent.getServiceName()); |
| for (Iterator iterator = serviceMonitors.iterator(); iterator.hasNext();) { |
| ServiceMonitor serviceMonitor = (ServiceMonitor) iterator.next(); |
| try { |
| serviceMonitor.serviceWaitingToStop(serviceEvent); |
| } catch (Throwable e) { |
| errors.addAll(fireServiceNotificationError(serviceMonitor, serviceEvent, e)); |
| } |
| } |
| if (!errors.isEmpty()) { |
| throw new KernelErrorsError(errors); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void serviceStopError(ServiceEvent serviceEvent) { |
| List errors = new ArrayList(); |
| Set serviceMonitors = getServiceMonitors(serviceEvent.getServiceName()); |
| for (Iterator iterator = serviceMonitors.iterator(); iterator.hasNext();) { |
| ServiceMonitor serviceMonitor = (ServiceMonitor) iterator.next(); |
| try { |
| serviceMonitor.serviceStopError(serviceEvent); |
| } catch (Throwable e) { |
| errors.addAll(fireServiceNotificationError(serviceMonitor, serviceEvent, e)); |
| } |
| } |
| if (!errors.isEmpty()) { |
| throw new KernelErrorsError(errors); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void serviceStopped(ServiceEvent serviceEvent) { |
| List errors = new ArrayList(); |
| Set serviceMonitors = getServiceMonitors(serviceEvent.getServiceName()); |
| for (Iterator iterator = serviceMonitors.iterator(); iterator.hasNext();) { |
| ServiceMonitor serviceMonitor = (ServiceMonitor) iterator.next(); |
| try { |
| serviceMonitor.serviceStopped(serviceEvent); |
| } catch (Throwable e) { |
| errors.addAll(fireServiceNotificationError(serviceMonitor, serviceEvent, e)); |
| } |
| } |
| if (!errors.isEmpty()) { |
| throw new KernelErrorsError(errors); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void serviceUnregistered(ServiceEvent serviceEvent) { |
| List errors = new ArrayList(); |
| Set serviceMonitors = getServiceMonitors(serviceEvent.getServiceName()); |
| for (Iterator iterator = serviceMonitors.iterator(); iterator.hasNext();) { |
| ServiceMonitor serviceMonitor = (ServiceMonitor) iterator.next(); |
| try { |
| serviceMonitor.serviceUnregistered(serviceEvent); |
| } catch (Throwable e) { |
| errors.addAll(fireServiceNotificationError(serviceMonitor, serviceEvent, e)); |
| } |
| } |
| if (!errors.isEmpty()) { |
| throw new KernelErrorsError(errors); |
| } |
| } |
| |
| private List fireServiceNotificationError(ServiceMonitor serviceMonitor, ServiceEvent serviceEvent, Throwable throwable) { |
| try { |
| kernelMonitor.serviceNotificationError(serviceMonitor, serviceEvent, throwable); |
| } catch (RuntimeException ignored) { |
| // ignore - we did our best to notify the world |
| } catch (KernelErrorsError e) { |
| return e.getErrors(); |
| } catch (Error e) { |
| return Collections.singletonList(e); |
| } |
| return Collections.EMPTY_LIST; |
| } |
| } |