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   * Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package java.nio.file;
  
  /**
   * An event or a repeated event for an object that is registered with a {@link
   * WatchService}.
   *
   * <p> An event is classified by its {@link #kind() kind} and has a {@link
   * #count() count} to indicate the number of times that the event has been
   * observed. This allows for efficient representation of repeated events. The
   * {@link #context() 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.
   *
   * <p> Watch events are immutable and safe for use by multiple concurrent
   * threads.
   *
   * @param   <T>     The type of the context object associated with the event
   *
   * @since 1.7
   */
  
  public interface WatchEvent<T> {
  
      /**
       * An event kind, for the purposes of identification.
       *
       * @since 1.7
       * @see StandardWatchEventKinds
       */
      public static interface Kind<T> {
          /**
           * Returns the name of the event kind.
           *
           * @return the name of the event kind
           */
          String name();
  
          /**
           * Returns the type of the {@link WatchEvent#context context} value.
           *
           *
           * @return the type of the context value
           */
          Class<T> type();
      }
  
      /**
       * An event modifier that qualifies how a {@link Watchable} is registered
       * with a {@link WatchService}.
       *
       * <p> This release does not define any <em>standard</em> modifiers.
       *
       * @since 1.7
       * @see Watchable#register
       */
      public static interface Modifier {
          /**
           * Returns the name of the modifier.
           *
           * @return the name of the modifier
           */
          String name();
      }
  
      /**
       * Returns the event kind.
       *
       * @return  the event kind
       */
      Kind<T> kind();
  
      /**
       * Returns the event count. If the event count is greater than {@code 1}
       * then this is a repeated event.
       *
       * @return  the event count
       */
      int count();
  
      /**
       * Returns the context for the event.
       *
       * <p> In the case of {@link StandardWatchEventKinds#ENTRY_CREATE ENTRY_CREATE},
       * {@link StandardWatchEventKinds#ENTRY_DELETE ENTRY_DELETE}, and {@link
       * StandardWatchEventKinds#ENTRY_MODIFY ENTRY_MODIFY} events the context is
       * a {@code Path} that is the {@link Path#relativize relative} path between
       * the directory registered with the watch service, and the entry that is
       * created, deleted, or modified.
       *
       * @return  the event context; may be {@code null}
       */
      T context();
  }
  