```
public final class ChannelAttributeKey
extends Object
```
Keys for attributes attached via AttributeMap.attr(AttributeKey).

Fields
Modifier and Type	Field	Description
`static io.netty.util.AttributeKey<ChannelDiagnostics>`	`CHANNEL_DIAGNOSTICS`
`static io.netty.util.AttributeKey<io.netty.handler.codec.http2.Http2Connection>`	`HTTP2_CONNECTION`
`static io.netty.util.AttributeKey<io.netty.handler.codec.http2.Http2FrameStream>`	`HTTP2_FRAME_STREAM`	The `Http2FrameStream` associated with this stream channel.
`static io.netty.util.AttributeKey<Integer>`	`HTTP2_INITIAL_WINDOW_SIZE`
`static io.netty.util.AttributeKey<Http2MultiplexedChannelPool>`	`HTTP2_MULTIPLEXED_CHANNEL_POOL`	Reference to `Http2MultiplexedChannelPool` which stores information about leased streams for a multiplexed connection.
`static io.netty.util.AttributeKey<Long>`	`MAX_CONCURRENT_STREAMS`	Value of the MAX_CONCURRENT_STREAMS from the server's SETTING frame.
`static io.netty.util.AttributeKey<PingTracker>`	`PING_TRACKER`
`static io.netty.util.AttributeKey<CompletableFuture<Protocol>>`	`PROTOCOL_FUTURE`	Future that when a protocol (http/1.1 or h2) has been selected.
`static io.netty.util.AttributeKey<Boolean>`	`STREAMING_COMPLETE_KEY`	`AttributeKey` to keep track of whether the streaming is completed and this is set to true when we receive the * `LastHttpContent`.

Method Summary
- Methods inherited from class java.lang.Object
  clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

public static final io.netty.util.AttributeKey<CompletableFuture<Protocol>> PROTOCOL_FUTURE

Future that when a protocol (http/1.1 or h2) has been selected.

HTTP2_MULTIPLEXED_CHANNEL_POOL
```
public static final io.netty.util.AttributeKey<Http2MultiplexedChannelPool> HTTP2_MULTIPLEXED_CHANNEL_POOL
```
Reference to Http2MultiplexedChannelPool which stores information about leased streams for a multiplexed connection.

public static final io.netty.util.AttributeKey<PingTracker> PING_TRACKER

public static final io.netty.util.AttributeKey<io.netty.handler.codec.http2.Http2Connection> HTTP2_CONNECTION

public static final io.netty.util.AttributeKey<Integer> HTTP2_INITIAL_WINDOW_SIZE

MAX_CONCURRENT_STREAMS
```
public static final io.netty.util.AttributeKey<Long> MAX_CONCURRENT_STREAMS
```
Value of the MAX_CONCURRENT_STREAMS from the server's SETTING frame.

HTTP2_FRAME_STREAM
```
public static final io.netty.util.AttributeKey<io.netty.handler.codec.http2.Http2FrameStream> HTTP2_FRAME_STREAM
```
The Http2FrameStream associated with this stream channel. This is added to stream channels when they are created, before they are fully initialized.

public static final io.netty.util.AttributeKey<ChannelDiagnostics> CHANNEL_DIAGNOSTICS

STREAMING_COMPLETE_KEY
```
public static final io.netty.util.AttributeKey<Boolean> STREAMING_COMPLETE_KEY
```
AttributeKey to keep track of whether the streaming is completed and this is set to true when we receive the * LastHttpContent.

Class ChannelAttributeKey