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 * accompanied this code).
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package sun.nio;

import java.nio.ByteBuffer;
import java.io.IOException;


This is an interface to adapt existing APIs to use 
ByteBuffers as the underlying data format. Only the initial producer and final consumer have to be changed. 
 For example, the Zip/Jar code supports InputStreams. To make the Zip code use MappedByteBuffers as the underlying data structure, it can create a class of InputStream that wraps the ByteBuffer, and implements the ByteBuffered interface. A co-operating class several layers away can ask the InputStream if it is an instance of ByteBuffered, then call the getByteBuffer() method. 
/**
 * This is an interface to adapt existing APIs to use {@link java.nio.ByteBuffer
 * ByteBuffers} as the underlying data format.  Only the initial producer and
 * final consumer have to be changed.
 *
 * <p>
 * For example, the Zip/Jar code supports {@link java.io.InputStream InputStreams}.
 * To make the Zip code use {@link java.nio.MappedByteBuffer MappedByteBuffers} as
 * the underlying data structure, it can create a class of InputStream that wraps
 * the ByteBuffer, and implements the ByteBuffered interface. A co-operating class
 * several layers away can ask the InputStream if it is an instance of ByteBuffered,
 * then call the {@link #getByteBuffer()} method.
 */
public interface ByteBuffered {

    
Returns the ByteBuffer behind this object, if this particular instance has one. An implementation of getByteBuffer() is allowed to return null for any reason. 
Throws:
Returns: The ByteBuffer, if this particular instance has one, or null otherwise.
Since: 1.5
/**
     * Returns the {@code ByteBuffer} behind this object, if this particular
     * instance has one. An implementation of {@code getByteBuffer()} is allowed
     * to return {@code null} for any reason.
     *
     * @return  The {@code ByteBuffer}, if this particular instance has one,
     *          or {@code null} otherwise.
     *
     * @throws  IOException
     *          If the ByteBuffer is no longer valid.
     *
     * @since  1.5
     */
    public ByteBuffer getByteBuffer() throws IOException;
}