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 * Copyright (c) 2015, 2020, 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
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 */

package jdk.internal.net.http.websocket;

import java.io.Closeable;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.ClosedChannelException;

/*
 * I/O abstraction used to implement WebSocket.
 *
 * @since 9
 */
public interface RawChannel extends Closeable {

    interface Provider {

        RawChannel rawChannel() throws IOException;
        void closeRawChannel() throws IOException;
    }

    interface RawEvent {

        /*
         * Returns the selector op flags this event is interested in.
         */
        int interestOps();

        /*
         * Called when event occurs.
         */
        void handle();
    }

    /*
     * Registers given event whose callback will be called once only (i.e.
     * register new event for each callback).
     *
     * Memory consistency effects: actions in a thread calling registerEvent
     * happen-before any subsequent actions in the thread calling event.handle
     */
    void registerEvent(RawEvent event) throws IOException;

    
Hands over the initial bytes. Once the bytes have been returned they are no longer available and the method will throw an IllegalStateException on each subsequent invocation. 
Throws:
IllegalStateException – 
        if the method has been already invoked
Returns:
the initial bytes/**
     * Hands over the initial bytes. Once the bytes have been returned they are
     * no longer available and the method will throw an {@link
     * IllegalStateException} on each subsequent invocation.
     *
     * @return the initial bytes
     * @throws IllegalStateException
     *         if the method has been already invoked
     */
    ByteBuffer initialByteBuffer() throws IllegalStateException;

    /*
     * Returns a ByteBuffer with the data read or null if EOF is reached. Has no
     * remaining bytes if no data available at the moment.
     */
    ByteBuffer read() throws IOException;

    /*
     * Writes a sequence of bytes to this channel from a subsequence of the
     * given buffers.
     */
    long write(ByteBuffer[] srcs, int offset, int length) throws IOException;

    
Shutdown the connection for reading without closing the channel.
 Once shutdown for reading then further reads on the channel will return null, the end-of-stream indication. If the input side of the connection is already shutdown then invoking this method has no effect. 
Throws:
ClosedChannelException – 
        If this channel is closed
IOException – 
        If some other I/O error occurs/**
     * Shutdown the connection for reading without closing the channel.
     *
     * <p> Once shutdown for reading then further reads on the channel will
     * return {@code null}, the end-of-stream indication. If the input side of
     * the connection is already shutdown then invoking this method has no
     * effect.
     *
     * @throws ClosedChannelException
     *         If this channel is closed
     * @throws IOException
     *         If some other I/O error occurs
     */
    void shutdownInput() throws IOException;

    
Shutdown the connection for writing without closing the channel.
 Once shutdown for writing then further attempts to write to the channel will throw ClosedChannelException. If the output side of the connection is already shutdown then invoking this method has no effect. 
Throws:
ClosedChannelException – 
        If this channel is closed
IOException – 
        If some other I/O error occurs/**
     * Shutdown the connection for writing without closing the channel.
     *
     * <p> Once shutdown for writing then further attempts to write to the
     * channel will throw {@link ClosedChannelException}. If the output side of
     * the connection is already shutdown then invoking this method has no
     * effect.
     *
     * @throws ClosedChannelException
     *         If this channel is closed
     * @throws IOException
     *         If some other I/O error occurs
     */
    void shutdownOutput() throws IOException;

    
Closes this channel.
Throws:
IOException – 
        If an I/O error occurs/**
     * Closes this channel.
     *
     * @throws IOException
     *         If an I/O error occurs
     */
    @Override
    void close() throws IOException;
}