/*
* Copyright 2013 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package io.netty.channel.group;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufHolder;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelId;
import io.netty.channel.ServerChannel;
import io.netty.util.ReferenceCountUtil;
import io.netty.util.concurrent.EventExecutor;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.StringUtil;
import java.util.AbstractSet;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicInteger;
/**
* The default {@link ChannelGroup} implementation.
*/
public class DefaultChannelGroup extends AbstractSet<Channel> implements ChannelGroup {
private static final AtomicInteger nextId = new AtomicInteger();
private final String name;
private final EventExecutor executor;
private final ConcurrentMap<ChannelId, Channel> serverChannels = PlatformDependent.newConcurrentHashMap();
private final ConcurrentMap<ChannelId, Channel> nonServerChannels = PlatformDependent.newConcurrentHashMap();
private final ChannelFutureListener remover = new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
remove(future.channel());
}
};
private final VoidChannelGroupFuture voidFuture = new VoidChannelGroupFuture(this);
private final boolean stayClosed;
private volatile boolean closed;
/**
* Creates a new group with a generated name and the provided {@link EventExecutor} to notify the
* {@link ChannelGroupFuture}s.
*/
public DefaultChannelGroup(EventExecutor executor) {
this(executor, false);
}
/**
* Creates a new group with the specified {@code name} and {@link EventExecutor} to notify the
* {@link ChannelGroupFuture}s. Please note that different groups can have the same name, which means no
* duplicate check is done against group names.
*/
public DefaultChannelGroup(String name, EventExecutor executor) {
this(name, executor, false);
}
/**
* Creates a new group with a generated name and the provided {@link EventExecutor} to notify the
* {@link ChannelGroupFuture}s. {@code stayClosed} defines whether or not, this group can be closed
* more than once. Adding channels to a closed group will immediately close them, too. This makes it
* easy, to shutdown server and child channels at once.
*/
public DefaultChannelGroup(EventExecutor executor, boolean stayClosed) {
this("group-0x" + Integer.toHexString(nextId.incrementAndGet()), executor, stayClosed);
}
/**
* Creates a new group with the specified {@code name} and {@link EventExecutor} to notify the
* {@link ChannelGroupFuture}s. {@code stayClosed} defines whether or not, this group can be closed
* more than once. Adding channels to a closed group will immediately close them, too. This makes it
* easy, to shutdown server and child channels at once. Please note that different groups can have
* the same name, which means no duplicate check is done against group names.
*/
public DefaultChannelGroup(String name, EventExecutor executor, boolean stayClosed) {
if (name == null) {
throw new NullPointerException("name");
}
this.name = name;
this.executor = executor;
this.stayClosed = stayClosed;
}
@Override
public String name() {
return name;
}
@Override
public Channel find(ChannelId id) {
Channel c = nonServerChannels.get(id);
if (c != null) {
return c;
} else {
return serverChannels.get(id);
}
}
@Override
public boolean isEmpty() {
return nonServerChannels.isEmpty() && serverChannels.isEmpty();
}
@Override
public int size() {
return nonServerChannels.size() + serverChannels.size();
}
@Override
public boolean contains(Object o) {
if (o instanceof Channel) {
Channel c = (Channel) o;
if (o instanceof ServerChannel) {
return serverChannels.containsValue(c);
} else {
return nonServerChannels.containsValue(c);
}
} else {
return false;
}
}
@Override
public boolean add(Channel channel) {
ConcurrentMap<ChannelId, Channel> map =
channel instanceof ServerChannel? serverChannels : nonServerChannels;
boolean added = map.putIfAbsent(channel.id(), channel) == null;
if (added) {
channel.closeFuture().addListener(remover);
}
if (stayClosed && closed) {
// First add channel, than check if closed.
// Seems inefficient at first, but this way a volatile
// gives us enough synchronization to be thread-safe.
//
// If true: Close right away.
// (Might be closed a second time by ChannelGroup.close(), but this is ok)
//
// If false: Channel will definitely be closed by the ChannelGroup.
// (Because closed=true always happens-before ChannelGroup.close())
//
// See https://github.com/netty/netty/issues/4020
channel.close();
}
return added;
}
@Override
public boolean remove(Object o) {
Channel c = null;
if (o instanceof ChannelId) {
c = nonServerChannels.remove(o);
if (c == null) {
c = serverChannels.remove(o);
}
} else if (o instanceof Channel) {
c = (Channel) o;
if (c instanceof ServerChannel) {
c = serverChannels.remove(c.id());
} else {
c = nonServerChannels.remove(c.id());
}
}
if (c == null) {
return false;
}
c.closeFuture().removeListener(remover);
return true;
}
@Override
public void clear() {
nonServerChannels.clear();
serverChannels.clear();
}
@Override
public Iterator<Channel> iterator() {
return new CombinedIterator<Channel>(
serverChannels.values().iterator(),
nonServerChannels.values().iterator());
}
@Override
public Object[] toArray() {
Collection<Channel> channels = new ArrayList<Channel>(size());
channels.addAll(serverChannels.values());
channels.addAll(nonServerChannels.values());
return channels.toArray();
}
@Override
public <T> T[] toArray(T[] a) {
Collection<Channel> channels = new ArrayList<Channel>(size());
channels.addAll(serverChannels.values());
channels.addAll(nonServerChannels.values());
return channels.toArray(a);
}
@Override
public ChannelGroupFuture close() {
return close(ChannelMatchers.all());
}
@Override
public ChannelGroupFuture disconnect() {
return disconnect(ChannelMatchers.all());
}
@Override
public ChannelGroupFuture deregister() {
return deregister(ChannelMatchers.all());
}
@Override
public ChannelGroupFuture write(Object message) {
return write(message, ChannelMatchers.all());
}
// Create a safe duplicate of the message to write it to a channel but not affect other writes.
// See https://github.com/netty/netty/issues/1461
private static Object safeDuplicate(Object message) {
if (message instanceof ByteBuf) {
return ((ByteBuf) message).retainedDuplicate();
} else if (message instanceof ByteBufHolder) {
return ((ByteBufHolder) message).retainedDuplicate();
} else {
return ReferenceCountUtil.retain(message);
}
}
@Override
public ChannelGroupFuture write(Object message, ChannelMatcher matcher) {
return write(message, matcher, false);
}
@Override
public ChannelGroupFuture write(Object message, ChannelMatcher matcher, boolean voidPromise) {
if (message == null) {
throw new NullPointerException("message");
}
if (matcher == null) {
throw new NullPointerException("matcher");
}
final ChannelGroupFuture future;
if (voidPromise) {
for (Channel c: nonServerChannels.values()) {
if (matcher.matches(c)) {
c.write(safeDuplicate(message), c.voidPromise());
}
}
future = voidFuture;
} else {
Map<Channel, ChannelFuture> futures = new LinkedHashMap<Channel, ChannelFuture>(size());
for (Channel c: nonServerChannels.values()) {
if (matcher.matches(c)) {
futures.put(c, c.write(safeDuplicate(message)));
}
}
future = new DefaultChannelGroupFuture(this, futures, executor);
}
ReferenceCountUtil.release(message);
return future;
}
@Override
public ChannelGroup flush() {
return flush(ChannelMatchers.all());
}
@Override
public ChannelGroupFuture flushAndWrite(Object message) {
return writeAndFlush(message);
}
@Override
public ChannelGroupFuture writeAndFlush(Object message) {
return writeAndFlush(message, ChannelMatchers.all());
}
@Override
public ChannelGroupFuture disconnect(ChannelMatcher matcher) {
if (matcher == null) {
throw new NullPointerException("matcher");
}
Map<Channel, ChannelFuture> futures =
new LinkedHashMap<Channel, ChannelFuture>(size());
for (Channel c: serverChannels.values()) {
if (matcher.matches(c)) {
futures.put(c, c.disconnect());
}
}
for (Channel c: nonServerChannels.values()) {
if (matcher.matches(c)) {
futures.put(c, c.disconnect());
}
}
return new DefaultChannelGroupFuture(this, futures, executor);
}
@Override
public ChannelGroupFuture close(ChannelMatcher matcher) {
if (matcher == null) {
throw new NullPointerException("matcher");
}
Map<Channel, ChannelFuture> futures =
new LinkedHashMap<Channel, ChannelFuture>(size());
if (stayClosed) {
// It is important to set the closed to true, before closing channels.
// Our invariants are:
// closed=true happens-before ChannelGroup.close()
// ChannelGroup.add() happens-before checking closed==true
//
// See https://github.com/netty/netty/issues/4020
closed = true;
}
for (Channel c: serverChannels.values()) {
if (matcher.matches(c)) {
futures.put(c, c.close());
}
}
for (Channel c: nonServerChannels.values()) {
if (matcher.matches(c)) {
futures.put(c, c.close());
}
}
return new DefaultChannelGroupFuture(this, futures, executor);
}
@Override
public ChannelGroupFuture deregister(ChannelMatcher matcher) {
if (matcher == null) {
throw new NullPointerException("matcher");
}
Map<Channel, ChannelFuture> futures =
new LinkedHashMap<Channel, ChannelFuture>(size());
for (Channel c: serverChannels.values()) {
if (matcher.matches(c)) {
futures.put(c, c.deregister());
}
}
for (Channel c: nonServerChannels.values()) {
if (matcher.matches(c)) {
futures.put(c, c.deregister());
}
}
return new DefaultChannelGroupFuture(this, futures, executor);
}
@Override
public ChannelGroup flush(ChannelMatcher matcher) {
for (Channel c: nonServerChannels.values()) {
if (matcher.matches(c)) {
c.flush();
}
}
return this;
}
@Override
public ChannelGroupFuture flushAndWrite(Object message, ChannelMatcher matcher) {
return writeAndFlush(message, matcher);
}
@Override
public ChannelGroupFuture writeAndFlush(Object message, ChannelMatcher matcher) {
return writeAndFlush(message, matcher, false);
}
@Override
public ChannelGroupFuture writeAndFlush(Object message, ChannelMatcher matcher, boolean voidPromise) {
if (message == null) {
throw new NullPointerException("message");
}
final ChannelGroupFuture future;
if (voidPromise) {
for (Channel c: nonServerChannels.values()) {
if (matcher.matches(c)) {
c.writeAndFlush(safeDuplicate(message), c.voidPromise());
}
}
future = voidFuture;
} else {
Map<Channel, ChannelFuture> futures = new LinkedHashMap<Channel, ChannelFuture>(size());
for (Channel c: nonServerChannels.values()) {
if (matcher.matches(c)) {
futures.put(c, c.writeAndFlush(safeDuplicate(message)));
}
}
future = new DefaultChannelGroupFuture(this, futures, executor);
}
ReferenceCountUtil.release(message);
return future;
}
@Override
public ChannelGroupFuture newCloseFuture() {
return newCloseFuture(ChannelMatchers.all());
}
@Override
public ChannelGroupFuture newCloseFuture(ChannelMatcher matcher) {
Map<Channel, ChannelFuture> futures =
new LinkedHashMap<Channel, ChannelFuture>(size());
for (Channel c: serverChannels.values()) {
if (matcher.matches(c)) {
futures.put(c, c.closeFuture());
}
}
for (Channel c: nonServerChannels.values()) {
if (matcher.matches(c)) {
futures.put(c, c.closeFuture());
}
}
return new DefaultChannelGroupFuture(this, futures, executor);
}
@Override
public int hashCode() {
return System.identityHashCode(this);
}
@Override
public boolean equals(Object o) {
return this == o;
}
@Override
public int compareTo(ChannelGroup o) {
int v = name().compareTo(o.name());
if (v != 0) {
return v;
}
return System.identityHashCode(this) - System.identityHashCode(o);
}
@Override
public String toString() {
return StringUtil.simpleClassName(this) + "(name: " + name() + ", size: " + size() + ')';
}
}