io.netty.channel.group

接口 ChannelGroup

所有超级接口:

java.util.Collection<Channel>, java.lang.Comparable<ChannelGroup>, java.lang.Iterable<Channel>, java.util.Set<Channel>

所有已知实现类:

DefaultChannelGroup

public interface ChannelGroup
extends java.util.Set<Channel>, java.lang.Comparable<ChannelGroup>

A thread-safe Set that contains open Channels and provides various bulk operations on them. Using ChannelGroup, you can categorize Channels into a meaningful group (e.g. on a per-service or per-state basis.) A closed Channel is automatically removed from the collection, so that you don't need to worry about the life cycle of the added Channel. A Channel can belong to more than one ChannelGroup.

Broadcast a message to multiple Channels

If you need to broadcast a message to more than one Channel, you can add the Channels associated with the recipients and call write(Object):

 ChannelGroup recipients =
         new DefaultChannelGroup(GlobalEventExecutor.INSTANCE);
 recipients.add(channelA);
 recipients.add(channelB);
 ..
 recipients.write(Unpooled.copiedBuffer(
         "Service will shut down for maintenance in 5 minutes.",
         CharsetUtil.UTF_8));
 

Simplify shutdown process with ChannelGroup

If both ServerChannels and non-ServerChannels exist in the same ChannelGroup, any requested I/O operations on the group are performed for the ServerChannels first and then for the others.

This rule is very useful when you shut down a server in one shot:

 ChannelGroup allChannels =
         new DefaultChannelGroup(GlobalEventExecutor.INSTANCE);

 public static void main(String[] args) throws Exception {
     ServerBootstrap b = new ServerBootstrap(..);
     ...
     b.childHandler(new MyHandler());

     // Start the server
     b.getPipeline().addLast("handler", new MyHandler());
     Channel serverChannel = b.bind(..).sync();
     allChannels.add(serverChannel);

     ... Wait until the shutdown signal reception ...

     // Close the serverChannel and then all accepted connections.
     allChannels.close().awaitUninterruptibly();
 }

 public class MyHandler extends ChannelInboundHandlerAdapter {
      @Override
     public void channelActive(ChannelHandlerContext ctx) {
         // closed on shutdown.
         allChannels.add(ctx.channel());
         super.channelActive(ctx);
     }
 }
 

方法概要

限定符和类型	方法和说明
ChannelGroupFuture	close() Closes all Channels in this group.
ChannelGroupFuture	close(ChannelMatcher matcher) Closes all Channels in this group that are matched by the given ChannelMatcher.
ChannelGroupFuture	deregister() 已过时。 This method will be removed in the next major feature release. Deregister all Channels in this group from their EventLoop. Please note that this operation is asynchronous as ChannelOutboundInvoker.deregister() is.
ChannelGroupFuture	deregister(ChannelMatcher matcher) 已过时。 This method will be removed in the next major feature release. Deregister all Channels in this group from their EventLoop that are matched by the given ChannelMatcher. Please note that this operation is asynchronous as ChannelOutboundInvoker.deregister() is.
ChannelGroupFuture	disconnect() Disconnects all Channels in this group from their remote peers.
ChannelGroupFuture	disconnect(ChannelMatcher matcher) Disconnects all Channels in this group from their remote peers, that are matched by the given ChannelMatcher.
Channel	find(ChannelId id) Returns the Channel which has the specified ChannelId.
ChannelGroup	flush() Flush all Channels in this group.
ChannelGroup	flush(ChannelMatcher matcher) Flush all Channels in this group that are matched by the given ChannelMatcher.
ChannelGroupFuture	flushAndWrite(java.lang.Object message) 已过时。 Use writeAndFlush(Object) instead.
ChannelGroupFuture	flushAndWrite(java.lang.Object message, ChannelMatcher matcher) 已过时。 Use writeAndFlush(Object, ChannelMatcher) instead.
java.lang.String	name() Returns the name of this group.
ChannelGroupFuture	newCloseFuture() Returns the ChannelGroupFuture which will be notified when all Channels that are part of this ChannelGroup, at the time of calling, are closed.
ChannelGroupFuture	newCloseFuture(ChannelMatcher matcher) Returns the ChannelGroupFuture which will be notified when all Channels that are part of this ChannelGroup, at the time of calling, are closed.
ChannelGroupFuture	write(java.lang.Object message) Writes the specified message to all Channels in this group.
ChannelGroupFuture	write(java.lang.Object message, ChannelMatcher matcher) Writes the specified message to all Channels in this group that are matched by the given ChannelMatcher.
ChannelGroupFuture	write(java.lang.Object message, ChannelMatcher matcher, boolean voidPromise) Writes the specified message to all Channels in this group that are matched by the given ChannelMatcher.
ChannelGroupFuture	writeAndFlush(java.lang.Object message) Shortcut for calling write(Object) and flush().
ChannelGroupFuture	writeAndFlush(java.lang.Object message, ChannelMatcher matcher) Shortcut for calling write(Object) and flush() and only act on Channels that are matched by the ChannelMatcher.
ChannelGroupFuture	writeAndFlush(java.lang.Object message, ChannelMatcher matcher, boolean voidPromise) Shortcut for calling write(Object, ChannelMatcher, boolean) and flush() and only act on Channels that are matched by the ChannelMatcher.

从接口继承的方法 java.util.Set

add, addAll, clear, contains, containsAll, equals, hashCode, isEmpty, iterator, remove, removeAll, retainAll, size, spliterator, toArray, toArray

从接口继承的方法 java.util.Collection

parallelStream, removeIf, stream

从接口继承的方法 java.lang.Iterable

forEach

从接口继承的方法 java.lang.Comparable

compareTo

方法详细资料

name

java.lang.String name()

Returns the name of this group. A group name is purely for helping you to distinguish one group from others.

find

Channel find(ChannelId id)

Returns the Channel which has the specified ChannelId.

返回:

the matching Channel if found. null otherwise.

write

ChannelGroupFuture write(java.lang.Object message)

Writes the specified message to all Channels in this group. If the specified message is an instance of ByteBuf, it is automatically duplicated to avoid a race condition. The same is true for ByteBufHolder. Please note that this operation is asynchronous as ChannelOutboundInvoker.write(Object) is.

返回:

itself

write

ChannelGroupFuture write(java.lang.Object message,
                         ChannelMatcher matcher)

Writes the specified message to all Channels in this group that are matched by the given ChannelMatcher. If the specified message is an instance of ByteBuf, it is automatically duplicated to avoid a race condition. The same is true for ByteBufHolder. Please note that this operation is asynchronous as ChannelOutboundInvoker.write(Object) is.

返回:

the ChannelGroupFuture instance that notifies when the operation is done for all channels

write

ChannelGroupFuture write(java.lang.Object message,
                         ChannelMatcher matcher,
                         boolean voidPromise)

Writes the specified message to all Channels in this group that are matched by the given ChannelMatcher. If the specified message is an instance of ByteBuf, it is automatically duplicated to avoid a race condition. The same is true for ByteBufHolder. Please note that this operation is asynchronous as ChannelOutboundInvoker.write(Object) is. If voidPromise is true ChannelOutboundInvoker.voidPromise() is used for the writes and so the same restrictions to the returned ChannelGroupFuture apply as to a void promise.

返回:

the ChannelGroupFuture instance that notifies when the operation is done for all channels

flush

ChannelGroup flush()

Flush all Channels in this group. If the specified messages are an instance of ByteBuf, it is automatically duplicated to avoid a race condition. Please note that this operation is asynchronous as ChannelOutboundInvoker.write(Object) is.

返回:

the ChannelGroupFuture instance that notifies when the operation is done for all channels

flush

ChannelGroup flush(ChannelMatcher matcher)

Flush all Channels in this group that are matched by the given ChannelMatcher. If the specified messages are an instance of ByteBuf, it is automatically duplicated to avoid a race condition. Please note that this operation is asynchronous as ChannelOutboundInvoker.write(Object) is.

返回:

the ChannelGroupFuture instance that notifies when the operation is done for all channels

writeAndFlush

ChannelGroupFuture writeAndFlush(java.lang.Object message)

Shortcut for calling write(Object) and flush().

flushAndWrite

@Deprecated
ChannelGroupFuture flushAndWrite(java.lang.Object message)

已过时。 Use writeAndFlush(Object) instead.

writeAndFlush

ChannelGroupFuture writeAndFlush(java.lang.Object message,
                                 ChannelMatcher matcher)

Shortcut for calling write(Object) and flush() and only act on Channels that are matched by the ChannelMatcher.

writeAndFlush

ChannelGroupFuture writeAndFlush(java.lang.Object message,
                                 ChannelMatcher matcher,
                                 boolean voidPromise)

Shortcut for calling write(Object, ChannelMatcher, boolean) and flush() and only act on Channels that are matched by the ChannelMatcher.

flushAndWrite

@Deprecated
ChannelGroupFuture flushAndWrite(java.lang.Object message,
                                              ChannelMatcher matcher)

已过时。 Use writeAndFlush(Object, ChannelMatcher) instead.

disconnect

ChannelGroupFuture disconnect()

Disconnects all Channels in this group from their remote peers.

返回:

the ChannelGroupFuture instance that notifies when the operation is done for all channels

disconnect

ChannelGroupFuture disconnect(ChannelMatcher matcher)

Disconnects all Channels in this group from their remote peers, that are matched by the given ChannelMatcher.

返回:

the ChannelGroupFuture instance that notifies when the operation is done for all channels

close

ChannelGroupFuture close()

Closes all Channels in this group. If the Channel is connected to a remote peer or bound to a local address, it is automatically disconnected and unbound.

返回:

the ChannelGroupFuture instance that notifies when the operation is done for all channels

close

ChannelGroupFuture close(ChannelMatcher matcher)

Closes all Channels in this group that are matched by the given ChannelMatcher. If the Channel is connected to a remote peer or bound to a local address, it is automatically disconnected and unbound.

返回:

the ChannelGroupFuture instance that notifies when the operation is done for all channels

deregister

@Deprecated
ChannelGroupFuture deregister()

已过时。 This method will be removed in the next major feature release. Deregister all Channels in this group from their EventLoop. Please note that this operation is asynchronous as ChannelOutboundInvoker.deregister() is.

返回:

the ChannelGroupFuture instance that notifies when the operation is done for all channels

deregister

@Deprecated
ChannelGroupFuture deregister(ChannelMatcher matcher)

已过时。 This method will be removed in the next major feature release. Deregister all Channels in this group from their EventLoop that are matched by the given ChannelMatcher. Please note that this operation is asynchronous as ChannelOutboundInvoker.deregister() is.

返回:

the ChannelGroupFuture instance that notifies when the operation is done for all channels

newCloseFuture

ChannelGroupFuture newCloseFuture()

Returns the ChannelGroupFuture which will be notified when all Channels that are part of this ChannelGroup, at the time of calling, are closed.

newCloseFuture

ChannelGroupFuture newCloseFuture(ChannelMatcher matcher)

Returns the ChannelGroupFuture which will be notified when all Channels that are part of this ChannelGroup, at the time of calling, are closed.