WatchEvent (Java Platform SE 8 )
Keywords: java.nio.file.WatchEvent interface
Date: 2026-03-16

compact1, compact2, compact3
java.nio.file

## Interface WatchEvent<T>

- Type Parameters:
    `T` - The type of the context object associated with the event

      public interface WatchEvent<T>

  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.

  Since:
    1.7

- - ### Nested Class Summary

    Nested Classes
    Modifier and Type | Interface and Description
    --- | ---
    `static interface` | `WatchEvent.Kind<T>` An event kind, for the purposes of identification.
    `static interface` | `WatchEvent.Modifier` An event modifier that qualifies how a `Watchable` is registered with a `WatchService`.

  - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method and Description
    --- | ---
    `T` | `context()` Returns the context for the event.
    `int` | `count()` Returns the event count.
    `WatchEvent.Kind<T>` | `kind()` Returns the event kind.

- - ### Method Detail

    - #### kind

          WatchEvent.Kind<T> kind()

      Returns the event kind.
      Returns:
        the event kind

    - #### count

          int count()

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

    - #### context

          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`

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