WatchEvent

  • WatchEvent represents an event (or repeated event) for an object registered with a WatchService, providing information about changes to the watched object.

  • Each event has a kind (type of event), a count (number of occurrences), and a context (object-specific information).

  • Events can indicate file creation, deletion, or modification within a watched directory, with the context often being the relative path to the affected file.

  • The WatchEvent interface provides methods to access these event details, aiding in monitoring and managing changes to registered files and directories.

  • These events are immutable, ensuring safe access from multiple threads.
public interface WatchEvent

An event or a repeated event for an object that is registered with a WatchService.

An event is classified by its kind and has a count to indicate the number of times that the event has been observed. This allows for efficient representation of repeated events. The context method returns any context associated with the event. In the case of a repeated event then the context is the same for all events.

Watch events are immutable and safe for use by multiple concurrent threads.

Nested Class Summary

interface WatchEvent.Kind<T> An event kind, for the purposes of identification. 
interface WatchEvent.Modifier An event modifier that qualifies how a Watchable is registered with a WatchService. 

Public Method Summary

abstract T
context()
Returns the context for the event.
abstract int
count()
Returns the event count.
abstract Kind<T>
kind()
Returns the event kind.

Public Methods

public abstract T context ()

Returns the context for the event.

In the case of ENTRY_CREATE, ENTRY_DELETE, and ENTRY_MODIFY events the context is a Path that is the relative path between the directory registered with the watch service, and the entry that is created, deleted, or modified.

Returns
  • the event context; may be null

public abstract int count ()

Returns the event count. If the event count is greater than 1 then this is a repeated event.

Returns
  • the event count

public abstract Kind<T> kind ()

Returns the event kind.

Returns
  • the event kind