/*
* Copyright 2011 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 org.jboss.netty.channel;
import java.net.SocketAddress;
import java.util.concurrent.ConcurrentMap;
import org.jboss.netty.util.internal.ConcurrentHashMap;
/**
* A skeletal {@link Channel} implementation.
*/
public abstract class AbstractChannel implements Channel {
static final ConcurrentMap<Integer, Channel> allChannels = new ConcurrentHashMap<Integer, Channel>();
private static Integer allocateId(Channel channel) {
Integer id = Integer.valueOf(System.identityHashCode(channel));
for (;;) {
// Loop until a unique ID is acquired.
// It should be found in one loop practically.
if (allChannels.putIfAbsent(id, channel) == null) {
// Successfully acquired.
return id;
} else {
// Taken by other channel at almost the same moment.
id = Integer.valueOf(id.intValue() + 1);
}
}
}
private final Integer id;
private final Channel parent;
private final ChannelFactory factory;
private final ChannelPipeline pipeline;
private final ChannelFuture succeededFuture = new SucceededChannelFuture(this);
private final ChannelCloseFuture closeFuture = new ChannelCloseFuture();
private volatile int interestOps = OP_READ;
/** Cache for the string representation of this channel */
private boolean strValConnected;
private String strVal;
/**
* Creates a new instance.
*
* @param parent
* the parent of this channel. {@code null} if there's no parent.
* @param factory
* the factory which created this channel
* @param pipeline
* the pipeline which is going to be attached to this channel
* @param sink
* the sink which will receive downstream events from the pipeline
* and send upstream events to the pipeline
*/
protected AbstractChannel(
Channel parent, ChannelFactory factory,
ChannelPipeline pipeline, ChannelSink sink) {
this.parent = parent;
this.factory = factory;
this.pipeline = pipeline;
id = allocateId(this);
pipeline.attach(this, sink);
}
/**
* (Internal use only) Creates a new temporary instance with the specified
* ID.
*
* @param parent
* the parent of this channel. {@code null} if there's no parent.
* @param factory
* the factory which created this channel
* @param pipeline
* the pipeline which is going to be attached to this channel
* @param sink
* the sink which will receive downstream events from the pipeline
* and send upstream events to the pipeline
*/
protected AbstractChannel(
Integer id,
Channel parent, ChannelFactory factory,
ChannelPipeline pipeline, ChannelSink sink) {
this.id = id;
this.parent = parent;
this.factory = factory;
this.pipeline = pipeline;
pipeline.attach(this, sink);
}
public final Integer getId() {
return id;
}
public Channel getParent() {
return parent;
}
public ChannelFactory getFactory() {
return factory;
}
public ChannelPipeline getPipeline() {
return pipeline;
}
/**
* Returns the cached {@link SucceededChannelFuture} instance.
*/
protected ChannelFuture getSucceededFuture() {
return succeededFuture;
}
/**
* Returns the {@link FailedChannelFuture} whose cause is an
* {@link UnsupportedOperationException}.
*/
protected ChannelFuture getUnsupportedOperationFuture() {
return new FailedChannelFuture(this, new UnsupportedOperationException());
}
/**
* Returns the {@linkplain System#identityHashCode(Object) identity hash code}
* of this channel.
*/
@Override
public final int hashCode() {
return System.identityHashCode(this);
}
/**
* Returns {@code true} if and only if the specified object is identical
* with this channel (i.e: {@code this == o}).
*/
@Override
public final boolean equals(Object o) {
return this == o;
}
/**
* Compares the {@linkplain #getId() ID} of the two channels.
*/
public final int compareTo(Channel o) {
return getId().compareTo(o.getId());
}
public boolean isOpen() {
return !closeFuture.isDone();
}
/**
* Marks this channel as closed. This method is intended to be called by
* an internal component - please do not call it unless you know what you
* are doing.
*
* @return {@code true} if and only if this channel was not marked as
* closed yet
*/
protected boolean setClosed() {
// Deallocate the current channel's ID from allChannels so that other
// new channels can use it.
allChannels.remove(id);
return closeFuture.setClosed();
}
public ChannelFuture bind(SocketAddress localAddress) {
return Channels.bind(this, localAddress);
}
public ChannelFuture unbind() {
return Channels.unbind(this);
}
public ChannelFuture close() {
ChannelFuture returnedCloseFuture = Channels.close(this);
assert closeFuture == returnedCloseFuture;
return closeFuture;
}
public ChannelFuture getCloseFuture() {
return closeFuture;
}
public ChannelFuture connect(SocketAddress remoteAddress) {
return Channels.connect(this, remoteAddress);
}
public ChannelFuture disconnect() {
return Channels.disconnect(this);
}
public int getInterestOps() {
return interestOps;
}
public ChannelFuture setInterestOps(int interestOps) {
return Channels.setInterestOps(this, interestOps);
}
/**
* Sets the {@link #getInterestOps() interestOps} property of this channel
* immediately. This method is intended to be called by an internal
* component - please do not call it unless you know what you are doing.
*/
protected void setInterestOpsNow(int interestOps) {
this.interestOps = interestOps;
}
public boolean isReadable() {
return (getInterestOps() & OP_READ) != 0;
}
public boolean isWritable() {
return (getInterestOps() & OP_WRITE) == 0;
}
public ChannelFuture setReadable(boolean readable) {
if (readable) {
return setInterestOps(getInterestOps() | OP_READ);
} else {
return setInterestOps(getInterestOps() & ~OP_READ);
}
}
public ChannelFuture write(Object message) {
return Channels.write(this, message);
}
public ChannelFuture write(Object message, SocketAddress remoteAddress) {
return Channels.write(this, message, remoteAddress);
}
/**
* Returns the {@link String} representation of this channel. The returned
* string contains the {@linkplain #getId() ID}, {@linkplain #getLocalAddress() local address},
* and {@linkplain #getRemoteAddress() remote address} of this channel for
* easier identification.
*/
@Override
public String toString() {
boolean connected = isConnected();
if (strValConnected == connected && strVal != null) {
return strVal;
}
StringBuilder buf = new StringBuilder(128);
buf.append("[id: 0x");
buf.append(getIdString());
SocketAddress localAddress = getLocalAddress();
SocketAddress remoteAddress = getRemoteAddress();
if (remoteAddress != null) {
buf.append(", ");
if (getParent() == null) {
buf.append(localAddress);
buf.append(connected? " => " : " :> ");
buf.append(remoteAddress);
} else {
buf.append(remoteAddress);
buf.append(connected? " => " : " :> ");
buf.append(localAddress);
}
} else if (localAddress != null) {
buf.append(", ");
buf.append(localAddress);
}
buf.append(']');
String strVal = buf.toString();
this.strVal = strVal;
strValConnected = connected;
return strVal;
}
private String getIdString() {
String answer = Integer.toHexString(id.intValue());
switch (answer.length()) {
case 0:
answer = "00000000";
break;
case 1:
answer = "0000000" + answer;
break;
case 2:
answer = "000000" + answer;
break;
case 3:
answer = "00000" + answer;
break;
case 4:
answer = "0000" + answer;
break;
case 5:
answer = "000" + answer;
break;
case 6:
answer = "00" + answer;
break;
case 7:
answer = "0" + answer;
break;
}
return answer;
}
private final class ChannelCloseFuture extends DefaultChannelFuture {
public ChannelCloseFuture() {
super(AbstractChannel.this, false);
}
@Override
public boolean setSuccess() {
// User is not supposed to call this method - ignore silently.
return false;
}
@Override
public boolean setFailure(Throwable cause) {
// User is not supposed to call this method - ignore silently.
return false;
}
boolean setClosed() {
return super.setSuccess();
}
}
}