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   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   * This code is free software; you can redistribute it and/or modify it
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   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
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   *
   * 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
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   */
  
  package java.nio.channels;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  
  
  /**
   * A channel that can read bytes into a sequence of buffers.
   *
   * <p> A <i>scattering</i> read operation reads, in a single invocation, a
   * sequence of bytes into one or more of a given sequence of buffers.
   * Scattering reads are often useful when implementing network protocols or
   * file formats that, for example, group data into segments consisting of one
   * or more fixed-length headers followed by a variable-length body.  Similar
   * <i>gathering</i> write operations are defined in the {@link
   * GatheringByteChannel} interface.  </p>
   *
   *
   * @author Mark Reinhold
   * @author JSR-51 Expert Group
   * @since 1.4
   */
  
  public interface ScatteringByteChannel
      extends ReadableByteChannel
  {
  
      /**
       * Reads a sequence of bytes from this channel into a subsequence of the
       * given buffers.
       *
       * <p> An invocation of this method attempts to read up to <i>r</i> bytes
       * from this channel, where <i>r</i> is the total number of bytes remaining
       * the specified subsequence of the given buffer array, that is,
       *
       * <blockquote><pre>
       * dsts[offset].remaining()
       *     + dsts[offset+1].remaining()
       *     + ... + dsts[offset+length-1].remaining()</pre></blockquote>
       *
       * at the moment that this method is invoked.
       *
       * <p> Suppose that a byte sequence of length <i>n</i> is read, where
       * <tt>0</tt>&nbsp;<tt>&lt;=</tt>&nbsp;<i>n</i>&nbsp;<tt>&lt;=</tt>&nbsp;<i>r</i>.
       * Up to the first <tt>dsts[offset].remaining()</tt> bytes of this sequence
       * are transferred into buffer <tt>dsts[offset]</tt>, up to the next
       * <tt>dsts[offset+1].remaining()</tt> bytes are transferred into buffer
       * <tt>dsts[offset+1]</tt>, and so forth, until the entire byte sequence
       * is transferred into the given buffers.  As many bytes as possible are
       * transferred into each buffer, hence the final position of each updated
       * buffer, except the last updated buffer, is guaranteed to be equal to
       * that buffer's limit.
       *
       * <p> This method may be invoked at any time.  If another thread has
       * already initiated a read operation upon this channel, however, then an
       * invocation of this method will block until the first operation is
       * complete. </p>
       *
       * @param  dsts
       *         The buffers into which bytes are to be transferred
       *
       * @param  offset
       *         The offset within the buffer array of the first buffer into
       *         which bytes are to be transferred; must be non-negative and no
       *         larger than <tt>dsts.length</tt>
       *
       * @param  length
       *         The maximum number of buffers to be accessed; must be
       *         non-negative and no larger than
       *         <tt>dsts.length</tt>&nbsp;-&nbsp;<tt>offset</tt>
       *
       * @return The number of bytes read, possibly zero,
       *         or <tt>-1</tt> if the channel has reached end-of-stream
       *
       * @throws  IndexOutOfBoundsException
       *          If the preconditions on the <tt>offset</tt> and <tt>length</tt>
       *          parameters do not hold
       *
       * @throws  NonReadableChannelException
       *          If this channel was not opened for reading
       *
       * @throws  ClosedChannelException
       *          If this channel is closed
       *
       * @throws  AsynchronousCloseException
       *          If another thread closes this channel
       *          while the read operation is in progress
       *
       * @throws  ClosedByInterruptException
       *          If another thread interrupts the current thread
       *          while the read operation is in progress, thereby
       *          closing the channel and setting the current thread's
       *          interrupt status
       *
       * @throws  IOException
       *          If some other I/O error occurs
       */
      public long read(ByteBuffer[] dsts, int offset, int length)
          throws IOException;
  
      /**
       * Reads a sequence of bytes from this channel into the given buffers.
       *
       * <p> An invocation of this method of the form <tt>c.read(dsts)</tt>
       * behaves in exactly the same manner as the invocation
       *
       * <blockquote><pre>
       * c.read(dsts, 0, dsts.length);</pre></blockquote>
       *
       * @param  dsts
       *         The buffers into which bytes are to be transferred
       *
       * @return The number of bytes read, possibly zero,
       *         or <tt>-1</tt> if the channel has reached end-of-stream
       *
       * @throws  NonReadableChannelException
       *          If this channel was not opened for reading
       *
       * @throws  ClosedChannelException
       *          If this channel is closed
       *
       * @throws  AsynchronousCloseException
       *          If another thread closes this channel
       *          while the read operation is in progress
       *
       * @throws  ClosedByInterruptException
       *          If another thread interrupts the current thread
       *          while the read operation is in progress, thereby
       *          closing the channel and setting the current thread's
       *          interrupt status
       *
       * @throws  IOException
       *          If some other I/O error occurs
       */
      public long read(ByteBuffer[] dsts) throws IOException;
  
  }
  