jetty-spdy/spdy-core/src/main/java/org/eclipse/jetty/spdy/api/StreamStatus.java

//
//  ========================================================================
//  Copyright (c) 1995-2017 Mort Bay Consulting Pty. Ltd.
//  ------------------------------------------------------------------------
//  All rights reserved. This program and the accompanying materials
//  are made available under the terms of the Eclipse Public License v1.0
//  and Apache License v2.0 which accompanies this distribution.
//
//      The Eclipse Public License is available at
//      http://www.eclipse.org/legal/epl-v10.html
//
//      The Apache License v2.0 is available at
//      http://www.opensource.org/licenses/apache2.0.php
//
//  You may elect to redistribute this code under either of these licenses.
//  ========================================================================
//

package org.eclipse.jetty.spdy.api;

import java.util.HashMap;
import java.util.Map;

/**
 * <p>An enumeration of stream statuses.</p>
 */
public enum StreamStatus
{
    /**
     * <p>The stream status indicating a protocol error</p>
     */
    PROTOCOL_ERROR(1, 1),
    /**
     * <p>The stream status indicating that the stream is not valid</p>
     */
    INVALID_STREAM(2, 2),
    /**
     * <p>The stream status indicating that the stream has been refused</p>
     */
    REFUSED_STREAM(3, 3),
    /**
     * <p>The stream status indicating that the implementation does not support the SPDY version of the stream</p>
     */
    UNSUPPORTED_VERSION(4, 4),
    /**
     * <p>The stream status indicating that the stream is no longer needed</p>
     */
    CANCEL_STREAM(5, 5),
    /**
     * <p>The stream status indicating an implementation error</p>
     */
    INTERNAL_ERROR(6, 6),
    /**
     * <p>The stream status indicating a flow control error</p>
     */
    FLOW_CONTROL_ERROR(7, 7),
    /**
     * <p>The stream status indicating a stream opened more than once</p>
     */
    STREAM_IN_USE(-1, 8),
    /**
     * <p>The stream status indicating data on a stream already closed</p>
     */
    STREAM_ALREADY_CLOSED(-1, 9),
    /**
     * <p>The stream status indicating credentials not valid</p>
     */
    INVALID_CREDENTIALS(-1, 10),
    /**
     * <p>The stream status indicating that the implementation could not support a frame too large</p>
     */
    FRAME_TOO_LARGE(-1, 11);

    /**
     * @param version the SPDY protocol version
     * @param code the stream status code
     * @return a {@link StreamStatus} from the given version and code,
     * or null if no such status exists
     */
    public static StreamStatus from(short version, int code)
    {
        switch (version)
        {
            case SPDY.V2:
                return Codes.v2Codes.get(code);
            case SPDY.V3:
                return Codes.v3Codes.get(code);
            default:
                throw new IllegalStateException();
        }
    }

    private final int v2Code;
    private final int v3Code;

    private StreamStatus(int v2Code, int v3Code)
    {
        this.v2Code = v2Code;
        if (v2Code >= 0)
            Codes.v2Codes.put(v2Code, this);
        this.v3Code = v3Code;
        if (v3Code >= 0)
            Codes.v3Codes.put(v3Code, this);
    }

    /**
     * @param version the SPDY protocol version
     * @return the stream status code
     */
    public int getCode(short version)
    {
        switch (version)
        {
            case SPDY.V2:
                return v2Code;
            case SPDY.V3:
                return v3Code;
            default:
                throw new IllegalStateException();
        }
    }

    private static class Codes
    {
        private static final Map<Integer, StreamStatus> v2Codes = new HashMap<>();
        private static final Map<Integer, StreamStatus> v3Codes = new HashMap<>();
    }
}