1 /* 2 * Copyright 2016 The Netty Project 3 * 4 * The Netty Project licenses this file to you under the Apache License, 5 * version 2.0 (the "License"); you may not use this file except in compliance 6 * with the License. You may obtain a copy of the License at: 7 * 8 * https://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 13 * License for the specific language governing permissions and limitations 14 * under the License. 15 */ 16 package io.netty.handler.codec.http2; 17 18 import io.netty.buffer.ByteBuf; 19 import io.netty.buffer.ByteBufHolder; 20 21 /** 22 * HTTP/2 GOAWAY frame. 23 * 24 * <p>The last stream identifier <em>must not</em> be set by the application, but instead the 25 * relative {@link #extraStreamIds()} should be used. The {@link #lastStreamId()} will only be 26 * set for incoming GOAWAY frames by the HTTP/2 codec. 27 * 28 * <p>Graceful shutdown as described in the HTTP/2 spec can be accomplished by calling 29 * {@code #setExtraStreamIds(Integer.MAX_VALUE)}. 30 */ 31 public interface Http2GoAwayFrame extends Http2Frame, ByteBufHolder { 32 /** 33 * The reason for beginning closure of the connection. Represented as an HTTP/2 error code. 34 */ 35 long errorCode(); 36 37 /** 38 * The number of IDs to reserve for the receiver to use while GOAWAY is in transit. This allows 39 * for new streams currently en route to still be created, up to a point, which allows for very 40 * graceful shutdown of both sides. 41 */ 42 int extraStreamIds(); 43 44 /** 45 * Sets the number of IDs to reserve for the receiver to use while GOAWAY is in transit. 46 * 47 * @see #extraStreamIds 48 * @return {@code this} 49 */ 50 Http2GoAwayFrame setExtraStreamIds(int extraStreamIds); 51 52 /** 53 * Returns the last stream identifier if set, or {@code -1} else. 54 */ 55 int lastStreamId(); 56 57 /** 58 * Optional debugging information describing cause the GOAWAY. Will not be {@code null}, but may 59 * be empty. 60 */ 61 @Override 62 ByteBuf content(); 63 64 @Override 65 Http2GoAwayFrame copy(); 66 67 @Override 68 Http2GoAwayFrame duplicate(); 69 70 @Override 71 Http2GoAwayFrame retainedDuplicate(); 72 73 @Override 74 Http2GoAwayFrame replace(ByteBuf content); 75 76 @Override 77 Http2GoAwayFrame retain(); 78 79 @Override 80 Http2GoAwayFrame retain(int increment); 81 82 @Override 83 Http2GoAwayFrame touch(); 84 85 @Override 86 Http2GoAwayFrame touch(Object hint); 87 }