EventService (nessie-events-service 0.63.0 API)

java.lang.Object
- org.projectnessie.events.service.EventService

All Implemented Interfaces:

java.lang.AutoCloseable
```
public class EventService
extends java.lang.Object
implements java.lang.AutoCloseable
```
Base class for event services.
This class takes care of starting and stopping the subscribers, and provides helper methods for handling incoming results from the version store, and for firing events.
This class is meant to be used as a singleton. It provides all the required functionality to process and deliver events. Subclasses may override some of the protected methods to add support for tracing, or to implement more sophisticated delivery logic.

Field Summary

Fields
Modifier and Type	Field	Description
`protected EventConfig`	`config`
`static java.lang.String`	`EVENT_ID_MDC_KEY`
`protected EventFactory`	`factory`
`protected EventSubscribers`	`subscribers`
`static java.lang.String`	`SUBSCRIPTION_ID_MDC_KEY`

Constructor Summary

Constructors
Constructor Description

EventService(EventConfig config, EventFactory factory, EventSubscribers subscribers)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`close()`	Closes the event service by deactivating the subscribers.
`protected void`	`deliverEvent(org.projectnessie.events.api.Event event, org.projectnessie.events.spi.EventSubscriber subscriber, org.projectnessie.events.spi.EventSubscription subscription)`
`protected void`	`fireEvent(org.projectnessie.events.api.Event event)`	Forwards the event to all subscribers.
`void`	`onVersionStoreEvent(VersionStoreEvent event)`	Invoked when a result is received from the version store by `ResultCollector`, then forwarded to this service for delivery.
`void`	`start()`	Starts event delivery by activating the subscribers.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

SUBSCRIPTION_ID_MDC_KEY

public static final java.lang.String SUBSCRIPTION_ID_MDC_KEY

See Also:: Constant Field Values

EVENT_ID_MDC_KEY

public static final java.lang.String EVENT_ID_MDC_KEY

See Also:: Constant Field Values

config
```
protected final EventConfig config
```

factory
```
protected final EventFactory factory
```

subscribers

protected final EventSubscribers subscribers

Constructor Detail

EventService

public EventService(EventConfig config,
                    EventFactory factory,
                    EventSubscribers subscribers)

Method Detail
- start
```
public void start()
```
  Starts event delivery by activating the subscribers.
- close
```
public void close()
```
  Closes the event service by deactivating the subscribers.
  
  Specified by:
  
  close in interface java.lang.AutoCloseable
- onVersionStoreEvent
```
public void onVersionStoreEvent(VersionStoreEvent event)
```
  Invoked when a result is received from the version store by ResultCollector, then forwarded to this service for delivery.
  
  See Also:
  
  ResultCollector.accept(Result), ResultCollector.shouldProcess(Result)
- fireEvent
```
protected void fireEvent(org.projectnessie.events.api.Event event)
```
  Forwards the event to all subscribers.
- deliverEvent
```
protected void deliverEvent(org.projectnessie.events.api.Event event,
                            org.projectnessie.events.spi.EventSubscriber subscriber,
                            org.projectnessie.events.spi.EventSubscription subscription)
```