gcc/libjava/java/nio/channels/spi/AbstractInterruptibleChannel.java

/* AbstractInterruptibleChannel.java -- 
   Copyright (C) 2002 Free Software Foundation, Inc.

This file is part of GNU Classpath.

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it under the terms of the GNU General Public License as published by
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Linking this library statically or dynamically with other modules is
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
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package java.nio.channels.spi;

import java.io.IOException;
import java.nio.channels.Channel;
import java.nio.channels.InterruptibleChannel;

/**
 * @author Michael Koch
 * @since 1.4
 */
public abstract class AbstractInterruptibleChannel
  implements Channel, InterruptibleChannel
{
  boolean opened = true;

  /**
   * Initializes the channel.
   */
  protected AbstractInterruptibleChannel ()
  {
  }

  /**
   * Marks the beginning of an I/O operation that might block indefinitely.
   */
  protected final void begin ()
  {
  }
    
  /**
   * Closes the channel.
   * 
   * @exception IOException If an error occurs
   */
  public final void close () throws IOException
  {
    opened = false;
    implCloseChannel ();
  }

  /**
   * Marks the end of an I/O operation that might block indefinitely.
   * 
   * @exception AsynchronousCloseException If the channel was asynchronously
   * closed.
   * @exception ClosedByInterruptException If the thread blocked in the
   * I/O operation was interrupted.
   */
  protected final void end (boolean completed)
  {
  }   

  /**
   * Closes the channel.
   * 
   * @exception IOException If an error occurs
   */
  protected abstract void implCloseChannel () throws IOException;

  /**
   * Tells whether or not this channel is open.
   */
  public final boolean isOpen ()
  {
    return opened;
  }
}