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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* Copyright 2012 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:
*
* https://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;
import io.netty.buffer.ByteBufAllocator;
import io.netty.channel.socket.ChannelOutputShutdownEvent;
import io.netty.channel.socket.ChannelOutputShutdownException;
import io.netty.util.DefaultAttributeMap;
import io.netty.util.ReferenceCountUtil;
import io.netty.util.internal.ObjectUtil;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.UnstableApi;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import java.io.IOException;
import java.net.ConnectException;
import java.net.InetSocketAddress;
import java.net.NoRouteToHostException;
import java.net.SocketAddress;
import java.net.SocketException;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.NotYetConnectedException;
import java.util.concurrent.Executor;
import java.util.concurrent.RejectedExecutionException;
/**
* A skeletal {@link Channel} implementation.
*/
public abstract class AbstractChannel extends DefaultAttributeMap implements Channel {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(AbstractChannel.class);
private final Channel parent;
private final ChannelId id;
private final Unsafe unsafe;
private final DefaultChannelPipeline pipeline;
private final VoidChannelPromise unsafeVoidPromise = new VoidChannelPromise(this, false);
private final CloseFuture closeFuture = new CloseFuture(this);
private volatile SocketAddress localAddress;
private volatile SocketAddress remoteAddress;
private volatile EventLoop eventLoop;
private volatile boolean registered;
private boolean closeInitiated;
private Throwable initialCloseCause;
/** Cache for the string representation of this channel */
private boolean strValActive;
private String strVal;
/**
* Creates a new instance.
*
* @param parent
* the parent of this channel. {@code null} if there's no parent.
*/
protected AbstractChannel(Channel parent) {
this.parent = parent;
id = newId();
unsafe = newUnsafe();
pipeline = newChannelPipeline();
}
/**
* Creates a new instance.
*
* @param parent
* the parent of this channel. {@code null} if there's no parent.
*/
protected AbstractChannel(Channel parent, ChannelId id) {
this.parent = parent;
this.id = id;
unsafe = newUnsafe();
pipeline = newChannelPipeline();
}
protected final int maxMessagesPerWrite() {
ChannelConfig config = config();
if (config instanceof DefaultChannelConfig) {
return ((DefaultChannelConfig) config).getMaxMessagesPerWrite();
}
Integer value = config.getOption(ChannelOption.MAX_MESSAGES_PER_WRITE);
if (value == null) {
return Integer.MAX_VALUE;
}
return value;
}
@Override
public final ChannelId id() {
return id;
}
/**
* Returns a new {@link DefaultChannelId} instance. Subclasses may override this method to assign custom
* {@link ChannelId}s to {@link Channel}s that use the {@link AbstractChannel#AbstractChannel(Channel)} constructor.
*/
protected ChannelId newId() {
return DefaultChannelId.newInstance();
}
/**
* Returns a new {@link DefaultChannelPipeline} instance.
*/
protected DefaultChannelPipeline newChannelPipeline() {
return new DefaultChannelPipeline(this);
}
@Override
public boolean isWritable() {
ChannelOutboundBuffer buf = unsafe.outboundBuffer();
return buf != null && buf.isWritable();
}
@Override
public long bytesBeforeUnwritable() {
ChannelOutboundBuffer buf = unsafe.outboundBuffer();
// isWritable() is currently assuming if there is no outboundBuffer then the channel is not writable.
// We should be consistent with that here.
return buf != null ? buf.bytesBeforeUnwritable() : 0;
}
@Override
public long bytesBeforeWritable() {
ChannelOutboundBuffer buf = unsafe.outboundBuffer();
// isWritable() is currently assuming if there is no outboundBuffer then the channel is not writable.
// We should be consistent with that here.
return buf != null ? buf.bytesBeforeWritable() : Long.MAX_VALUE;
}
@Override
public Channel parent() {
return parent;
}
@Override
public ChannelPipeline pipeline() {
return pipeline;
}
@Override
public ByteBufAllocator alloc() {
return config().getAllocator();
}
@Override
public EventLoop eventLoop() {
EventLoop eventLoop = this.eventLoop;
if (eventLoop == null) {
throw new IllegalStateException("channel not registered to an event loop");
}
return eventLoop;
}
@Override
public SocketAddress localAddress() {
SocketAddress localAddress = this.localAddress;
if (localAddress == null) {
try {
this.localAddress = localAddress = unsafe().localAddress();
} catch (Error e) {
throw e;
} catch (Throwable t) {
// Sometimes fails on a closed socket in Windows.
return null;
}
}
return localAddress;
}
/**
* @deprecated no use-case for this.
*/
@Deprecated
protected void invalidateLocalAddress() {
localAddress = null;
}
@Override
public SocketAddress remoteAddress() {
SocketAddress remoteAddress = this.remoteAddress;
if (remoteAddress == null) {
try {
this.remoteAddress = remoteAddress = unsafe().remoteAddress();
} catch (Error e) {
throw e;
} catch (Throwable t) {
// Sometimes fails on a closed socket in Windows.
return null;
}
}
return remoteAddress;
}
/**
* @deprecated no use-case for this.
*/
@Deprecated
protected void invalidateRemoteAddress() {
remoteAddress = null;
}
@Override
public boolean isRegistered() {
return registered;
}
@Override
public ChannelFuture bind(SocketAddress localAddress) {
return pipeline.bind(localAddress);
}
@Override
public ChannelFuture connect(SocketAddress remoteAddress) {
return pipeline.connect(remoteAddress);
}
@Override
public ChannelFuture connect(SocketAddress remoteAddress, SocketAddress localAddress) {
return pipeline.connect(remoteAddress, localAddress);
}
@Override
public ChannelFuture disconnect() {
return pipeline.disconnect();
}
@Override
public ChannelFuture close() {
return pipeline.close();
}
@Override
public ChannelFuture deregister() {
return pipeline.deregister();
}
@Override
public Channel flush() {
pipeline.flush();
return this;
}
@Override
public ChannelFuture bind(SocketAddress localAddress, ChannelPromise promise) {
return pipeline.bind(localAddress, promise);
}
@Override
public ChannelFuture connect(SocketAddress remoteAddress, ChannelPromise promise) {
return pipeline.connect(remoteAddress, promise);
}
@Override
public ChannelFuture connect(SocketAddress remoteAddress, SocketAddress localAddress, ChannelPromise promise) {
return pipeline.connect(remoteAddress, localAddress, promise);
}
@Override
public ChannelFuture disconnect(ChannelPromise promise) {
return pipeline.disconnect(promise);
}
@Override
public ChannelFuture close(ChannelPromise promise) {
return pipeline.close(promise);
}
@Override
public ChannelFuture deregister(ChannelPromise promise) {
return pipeline.deregister(promise);
}
@Override
public Channel read() {
pipeline.read();
return this;
}
@Override
public ChannelFuture write(Object msg) {
return pipeline.write(msg);
}
@Override
public ChannelFuture write(Object msg, ChannelPromise promise) {
return pipeline.write(msg, promise);
}
@Override
public ChannelFuture writeAndFlush(Object msg) {
return pipeline.writeAndFlush(msg);
}
@Override
public ChannelFuture writeAndFlush(Object msg, ChannelPromise promise) {
return pipeline.writeAndFlush(msg, promise);
}
@Override
public ChannelPromise newPromise() {
return pipeline.newPromise();
}
@Override
public ChannelProgressivePromise newProgressivePromise() {
return pipeline.newProgressivePromise();
}
@Override
public ChannelFuture newSucceededFuture() {
return pipeline.newSucceededFuture();
}
@Override
public ChannelFuture newFailedFuture(Throwable cause) {
return pipeline.newFailedFuture(cause);
}
@Override
public ChannelFuture closeFuture() {
return closeFuture;
}
@Override
public Unsafe unsafe() {
return unsafe;
}
/**
* Create a new {@link AbstractUnsafe} instance which will be used for the life-time of the {@link Channel}
*/
protected abstract AbstractUnsafe newUnsafe();
/**
* Returns the ID of this channel.
*/
@Override
public final int hashCode() {
return id.hashCode();
}
/**
* 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;
}
@Override
public final int compareTo(Channel o) {
if (this == o) {
return 0;
}
return id().compareTo(o.id());
}
/**
* Returns the {@link String} representation of this channel. The returned
* string contains the {@linkplain #hashCode() ID}, {@linkplain #localAddress() local address},
* and {@linkplain #remoteAddress() remote address} of this channel for
* easier identification.
*/
@Override
public String toString() {
boolean active = isActive();
if (strValActive == active && strVal != null) {
return strVal;
}
SocketAddress remoteAddr = remoteAddress();
SocketAddress localAddr = localAddress();
if (remoteAddr != null) {
StringBuilder buf = new StringBuilder(96)
.append("[id: 0x")
.append(id.asShortText())
.append(", L:")
.append(localAddr)
.append(active? " - " : " ! ")
.append("R:")
.append(remoteAddr)
.append(']');
strVal = buf.toString();
} else if (localAddr != null) {
StringBuilder buf = new StringBuilder(64)
.append("[id: 0x")
.append(id.asShortText())
.append(", L:")
.append(localAddr)
.append(']');
strVal = buf.toString();
} else {
StringBuilder buf = new StringBuilder(16)
.append("[id: 0x")
.append(id.asShortText())
.append(']');
strVal = buf.toString();
}
strValActive = active;
return strVal;
}
@Override
public final ChannelPromise voidPromise() {
return pipeline.voidPromise();
}
/**
* {@link Unsafe} implementation which sub-classes must extend and use.
*/
protected abstract class AbstractUnsafe implements Unsafe {
private volatile ChannelOutboundBuffer outboundBuffer = new ChannelOutboundBuffer(AbstractChannel.this);
private RecvByteBufAllocator.Handle recvHandle;
private boolean inFlush0;
/** true if the channel has never been registered, false otherwise */
private boolean neverRegistered = true;
private void assertEventLoop() {
assert !registered || eventLoop.inEventLoop();
}
@Override
public RecvByteBufAllocator.Handle recvBufAllocHandle() {
if (recvHandle == null) {
recvHandle = config().getRecvByteBufAllocator().newHandle();
}
return recvHandle;
}
@Override
public final ChannelOutboundBuffer outboundBuffer() {
return outboundBuffer;
}
@Override
public final SocketAddress localAddress() {
return localAddress0();
}
@Override
public final SocketAddress remoteAddress() {
return remoteAddress0();
}
@Override
public final void register(EventLoop eventLoop, final ChannelPromise promise) {
ObjectUtil.checkNotNull(eventLoop, "eventLoop");
if (isRegistered()) {
promise.setFailure(new IllegalStateException("registered to an event loop already"));
return;
}
if (!isCompatible(eventLoop)) {
promise.setFailure(
new IllegalStateException("incompatible event loop type: " + eventLoop.getClass().getName()));
return;
}
AbstractChannel.this.eventLoop = eventLoop;
if (eventLoop.inEventLoop()) {
register0(promise);
} else {
try {
eventLoop.execute(new Runnable() {
@Override
public void run() {
register0(promise);
}
});
} catch (Throwable t) {
logger.warn(
"Force-closing a channel whose registration task was not accepted by an event loop: {}",
AbstractChannel.this, t);
closeForcibly();
closeFuture.setClosed();
safeSetFailure(promise, t);
}
}
}
private void register0(ChannelPromise promise) {
try {
// check if the channel is still open as it could be closed in the mean time when the register
// call was outside of the eventLoop
if (!promise.setUncancellable() || !ensureOpen(promise)) {
return;
}
boolean firstRegistration = neverRegistered;
doRegister();
neverRegistered = false;
registered = true;
// Ensure we call handlerAdded(...) before we actually notify the promise. This is needed as the
// user may already fire events through the pipeline in the ChannelFutureListener.
pipeline.invokeHandlerAddedIfNeeded();
safeSetSuccess(promise);
pipeline.fireChannelRegistered();
// Only fire a channelActive if the channel has never been registered. This prevents firing
// multiple channel actives if the channel is deregistered and re-registered.
if (isActive()) {
if (firstRegistration) {
pipeline.fireChannelActive();
} else if (config().isAutoRead()) {
// This channel was registered before and autoRead() is set. This means we need to begin read
// again so that we process inbound data.
//
// See https://github.com/netty/netty/issues/4805
beginRead();
}
}
} catch (Throwable t) {
// Close the channel directly to avoid FD leak.
closeForcibly();
closeFuture.setClosed();
safeSetFailure(promise, t);
}
}
@Override
public final void bind(final SocketAddress localAddress, final ChannelPromise promise) {
assertEventLoop();
if (!promise.setUncancellable() || !ensureOpen(promise)) {
return;
}
// See: https://github.com/netty/netty/issues/576
if (Boolean.TRUE.equals(config().getOption(ChannelOption.SO_BROADCAST)) &&
localAddress instanceof InetSocketAddress &&
!((InetSocketAddress) localAddress).getAddress().isAnyLocalAddress() &&
!PlatformDependent.isWindows() && !PlatformDependent.maybeSuperUser()) {
// Warn a user about the fact that a non-root user can't receive a
// broadcast packet on *nix if the socket is bound on non-wildcard address.
logger.warn(
"A non-root user can't receive a broadcast packet if the socket " +
"is not bound to a wildcard address; binding to a non-wildcard " +
"address (" + localAddress + ") anyway as requested.");
}
boolean wasActive = isActive();
try {
doBind(localAddress);
} catch (Throwable t) {
safeSetFailure(promise, t);
closeIfClosed();
return;
}
if (!wasActive && isActive()) {
invokeLater(new Runnable() {
@Override
public void run() {
pipeline.fireChannelActive();
}
});
}
safeSetSuccess(promise);
}
@Override
public final void disconnect(final ChannelPromise promise) {
assertEventLoop();
if (!promise.setUncancellable()) {
return;
}
boolean wasActive = isActive();
try {
doDisconnect();
// Reset remoteAddress and localAddress
remoteAddress = null;
localAddress = null;
} catch (Throwable t) {
safeSetFailure(promise, t);
closeIfClosed();
return;
}
if (wasActive && !isActive()) {
invokeLater(new Runnable() {
@Override
public void run() {
pipeline.fireChannelInactive();
}
});
}
safeSetSuccess(promise);
closeIfClosed(); // doDisconnect() might have closed the channel
}
@Override
public void close(final ChannelPromise promise) {
assertEventLoop();
ClosedChannelException closedChannelException =
StacklessClosedChannelException.newInstance(AbstractChannel.class, "close(ChannelPromise)");
close(promise, closedChannelException, closedChannelException, false);
}
/**
* Shutdown the output portion of the corresponding {@link Channel}.
* For example this will clean up the {@link ChannelOutboundBuffer} and not allow any more writes.
*/
@UnstableApi
public final void shutdownOutput(final ChannelPromise promise) {
assertEventLoop();
shutdownOutput(promise, null);
}
/**
* Shutdown the output portion of the corresponding {@link Channel}.
* For example this will clean up the {@link ChannelOutboundBuffer} and not allow any more writes.
* @param cause The cause which may provide rational for the shutdown.
*/
private void shutdownOutput(final ChannelPromise promise, Throwable cause) {
if (!promise.setUncancellable()) {
return;
}
final ChannelOutboundBuffer outboundBuffer = this.outboundBuffer;
if (outboundBuffer == null) {
promise.setFailure(new ClosedChannelException());
return;
}
this.outboundBuffer = null; // Disallow adding any messages and flushes to outboundBuffer.
final Throwable shutdownCause = cause == null ?
new ChannelOutputShutdownException("Channel output shutdown") :
new ChannelOutputShutdownException("Channel output shutdown", cause);
// When a side enables SO_LINGER and calls showdownOutput(...) to start TCP half-closure
// we can not call doDeregister here because we should ensure this side in fin_wait2 state
// can still receive and process the data which is send by another side in the close_wait state。
// See https://github.com/netty/netty/issues/11981
try {
// The shutdown function does not block regardless of the SO_LINGER setting on the socket
// so we don't need to use GlobalEventExecutor to execute the shutdown
doShutdownOutput();
promise.setSuccess();
} catch (Throwable err) {
promise.setFailure(err);
} finally {
closeOutboundBufferForShutdown(pipeline, outboundBuffer, shutdownCause);
}
}
private void closeOutboundBufferForShutdown(
ChannelPipeline pipeline, ChannelOutboundBuffer buffer, Throwable cause) {
buffer.failFlushed(cause, false);
buffer.close(cause, true);
pipeline.fireUserEventTriggered(ChannelOutputShutdownEvent.INSTANCE);
}
private void close(final ChannelPromise promise, final Throwable cause,
final ClosedChannelException closeCause, final boolean notify) {
if (!promise.setUncancellable()) {
return;
}
if (closeInitiated) {
if (closeFuture.isDone()) {
// Closed already.
safeSetSuccess(promise);
} else if (!(promise instanceof VoidChannelPromise)) { // Only needed if no VoidChannelPromise.
// This means close() was called before so we just register a listener and return
closeFuture.addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
promise.setSuccess();
}
});
}
return;
}
closeInitiated = true;
final boolean wasActive = isActive();
final ChannelOutboundBuffer outboundBuffer = this.outboundBuffer;
this.outboundBuffer = null; // Disallow adding any messages and flushes to outboundBuffer.
Executor closeExecutor = prepareToClose();
if (closeExecutor != null) {
closeExecutor.execute(new Runnable() {
@Override
public void run() {
try {
// Execute the close.
doClose0(promise);
} finally {
// Call invokeLater so closeAndDeregister is executed in the EventLoop again!
invokeLater(new Runnable() {
@Override
public void run() {
if (outboundBuffer != null) {
// Fail all the queued messages
outboundBuffer.failFlushed(cause, notify);
outboundBuffer.close(closeCause);
}
fireChannelInactiveAndDeregister(wasActive);
}
});
}
}
});
} else {
try {
// Close the channel and fail the queued messages in all cases.
doClose0(promise);
} finally {
if (outboundBuffer != null) {
// Fail all the queued messages.
outboundBuffer.failFlushed(cause, notify);
outboundBuffer.close(closeCause);
}
}
if (inFlush0) {
invokeLater(new Runnable() {
@Override
public void run() {
fireChannelInactiveAndDeregister(wasActive);
}
});
} else {
fireChannelInactiveAndDeregister(wasActive);
}
}
}
private void doClose0(ChannelPromise promise) {
try {
doClose();
closeFuture.setClosed();
safeSetSuccess(promise);
} catch (Throwable t) {
closeFuture.setClosed();
safeSetFailure(promise, t);
}
}
private void fireChannelInactiveAndDeregister(final boolean wasActive) {
deregister(voidPromise(), wasActive && !isActive());
}
@Override
public final void closeForcibly() {
assertEventLoop();
try {
doClose();
} catch (Exception e) {
logger.warn("Failed to close a channel.", e);
}
}
@Override
public final void deregister(final ChannelPromise promise) {
assertEventLoop();
deregister(promise, false);
}
private void deregister(final ChannelPromise promise, final boolean fireChannelInactive) {
if (!promise.setUncancellable()) {
return;
}
if (!registered) {
safeSetSuccess(promise);
return;
}
// As a user may call deregister() from within any method while doing processing in the ChannelPipeline,
// we need to ensure we do the actual deregister operation later. This is needed as for example,
// we may be in the ByteToMessageDecoder.callDecode(...) method and so still try to do processing in
// the old EventLoop while the user already registered the Channel to a new EventLoop. Without delay,
// the deregister operation this could lead to have a handler invoked by different EventLoop and so
// threads.
//
// See:
// https://github.com/netty/netty/issues/4435
invokeLater(new Runnable() {
@Override
public void run() {
try {
doDeregister();
} catch (Throwable t) {
logger.warn("Unexpected exception occurred while deregistering a channel.", t);
} finally {
if (fireChannelInactive) {
pipeline.fireChannelInactive();
}
// Some transports like local and AIO does not allow the deregistration of
// an open channel. Their doDeregister() calls close(). Consequently,
// close() calls deregister() again - no need to fire channelUnregistered, so check
// if it was registered.
if (registered) {
registered = false;
pipeline.fireChannelUnregistered();
}
safeSetSuccess(promise);
}
}
});
}
@Override
public final void beginRead() {
assertEventLoop();
try {
doBeginRead();
} catch (final Exception e) {
invokeLater(new Runnable() {
@Override
public void run() {
pipeline.fireExceptionCaught(e);
}
});
close(voidPromise());
}
}
@Override
public final void write(Object msg, ChannelPromise promise) {
assertEventLoop();
ChannelOutboundBuffer outboundBuffer = this.outboundBuffer;
if (outboundBuffer == null) {
try {
// release message now to prevent resource-leak
ReferenceCountUtil.release(msg);
} finally {
// If the outboundBuffer is null we know the channel was closed and so
// need to fail the future right away. If it is not null the handling of the rest
// will be done in flush0()
// See https://github.com/netty/netty/issues/2362
safeSetFailure(promise,
newClosedChannelException(initialCloseCause, "write(Object, ChannelPromise)"));
}
return;
}
int size;
try {
msg = filterOutboundMessage(msg);
size = pipeline.estimatorHandle().size(msg);
if (size < 0) {
size = 0;
}
} catch (Throwable t) {
try {
ReferenceCountUtil.release(msg);
} finally {
safeSetFailure(promise, t);
}
return;
}
outboundBuffer.addMessage(msg, size, promise);
}
@Override
public final void flush() {
assertEventLoop();
ChannelOutboundBuffer outboundBuffer = this.outboundBuffer;
if (outboundBuffer == null) {
return;
}
outboundBuffer.addFlush();
flush0();
}
@SuppressWarnings("deprecation")
protected void flush0() {
if (inFlush0) {
// Avoid re-entrance
return;
}
final ChannelOutboundBuffer outboundBuffer = this.outboundBuffer;
if (outboundBuffer == null || outboundBuffer.isEmpty()) {
return;
}
inFlush0 = true;
// Mark all pending write requests as failure if the channel is inactive.
if (!isActive()) {
try {
// Check if we need to generate the exception at all.
if (!outboundBuffer.isEmpty()) {
if (isOpen()) {
outboundBuffer.failFlushed(new NotYetConnectedException(), true);
} else {
// Do not trigger channelWritabilityChanged because the channel is closed already.
outboundBuffer.failFlushed(newClosedChannelException(initialCloseCause, "flush0()"), false);
}
}
} finally {
inFlush0 = false;
}
return;
}
try {
doWrite(outboundBuffer);
} catch (Throwable t) {
handleWriteError(t);
} finally {
inFlush0 = false;
}
}
protected final void handleWriteError(Throwable t) {
if (t instanceof IOException && config().isAutoClose()) {
/**
* Just call {@link #close(ChannelPromise, Throwable, boolean)} here which will take care of
* failing all flushed messages and also ensure the actual close of the underlying transport
* will happen before the promises are notified.
*
* This is needed as otherwise {@link #isActive()} , {@link #isOpen()} and {@link #isWritable()}
* may still return {@code true} even if the channel should be closed as result of the exception.
*/
initialCloseCause = t;
close(voidPromise(), t, newClosedChannelException(t, "flush0()"), false);
} else {
try {
shutdownOutput(voidPromise(), t);
} catch (Throwable t2) {
initialCloseCause = t;
close(voidPromise(), t2, newClosedChannelException(t, "flush0()"), false);
}
}
}
private ClosedChannelException newClosedChannelException(Throwable cause, String method) {
ClosedChannelException exception =
StacklessClosedChannelException.newInstance(AbstractChannel.AbstractUnsafe.class, method);
if (cause != null) {
exception.initCause(cause);
}
return exception;
}
@Override
public final ChannelPromise voidPromise() {
assertEventLoop();
return unsafeVoidPromise;
}
protected final boolean ensureOpen(ChannelPromise promise) {
if (isOpen()) {
return true;
}
safeSetFailure(promise, newClosedChannelException(initialCloseCause, "ensureOpen(ChannelPromise)"));
return false;
}
/**
* Marks the specified {@code promise} as success. If the {@code promise} is done already, log a message.
*/
protected final void safeSetSuccess(ChannelPromise promise) {
if (!(promise instanceof VoidChannelPromise) && !promise.trySuccess()) {
logger.warn("Failed to mark a promise as success because it is done already: {}", promise);
}
}
/**
* Marks the specified {@code promise} as failure. If the {@code promise} is done already, log a message.
*/
protected final void safeSetFailure(ChannelPromise promise, Throwable cause) {
if (!(promise instanceof VoidChannelPromise) && !promise.tryFailure(cause)) {
logger.warn("Failed to mark a promise as failure because it's done already: {}", promise, cause);
}
}
protected final void closeIfClosed() {
if (isOpen()) {
return;
}
close(voidPromise());
}
private void invokeLater(Runnable task) {
try {
// This method is used by outbound operation implementations to trigger an inbound event later.
// They do not trigger an inbound event immediately because an outbound operation might have been
// triggered by another inbound event handler method. If fired immediately, the call stack
// will look like this for example:
//
// handlerA.inboundBufferUpdated() - (1) an inbound handler method closes a connection.
// -> handlerA.ctx.close()
// -> channel.unsafe.close()
// -> handlerA.channelInactive() - (2) another inbound handler method called while in (1) yet
//
// which means the execution of two inbound handler methods of the same handler overlap undesirably.
eventLoop().execute(task);
} catch (RejectedExecutionException e) {
logger.warn("Can't invoke task later as EventLoop rejected it", e);
}
}
/**
* Appends the remote address to the message of the exceptions caused by connection attempt failure.
*/
protected final Throwable annotateConnectException(Throwable cause, SocketAddress remoteAddress) {
if (cause instanceof ConnectException) {
return new AnnotatedConnectException((ConnectException) cause, remoteAddress);
}
if (cause instanceof NoRouteToHostException) {
return new AnnotatedNoRouteToHostException((NoRouteToHostException) cause, remoteAddress);
}
if (cause instanceof SocketException) {
return new AnnotatedSocketException((SocketException) cause, remoteAddress);
}
return cause;
}
/**
* Prepares to close the {@link Channel}. If this method returns an {@link Executor}, the
* caller must call the {@link Executor#execute(Runnable)} method with a task that calls
* {@link #doClose()} on the returned {@link Executor}. If this method returns {@code null},
* {@link #doClose()} must be called from the caller thread. (i.e. {@link EventLoop})
*/
protected Executor prepareToClose() {
return null;
}
}
/**
* Return {@code true} if the given {@link EventLoop} is compatible with this instance.
*/
protected abstract boolean isCompatible(EventLoop loop);
/**
* Returns the {@link SocketAddress} which is bound locally.
*/
protected abstract SocketAddress localAddress0();
/**
* Return the {@link SocketAddress} which the {@link Channel} is connected to.
*/
protected abstract SocketAddress remoteAddress0();
/**
* Is called after the {@link Channel} is registered with its {@link EventLoop} as part of the register process.
*
* Sub-classes may override this method
*/
protected void doRegister() throws Exception {
// NOOP
}
/**
* Bind the {@link Channel} to the {@link SocketAddress}
*/
protected abstract void doBind(SocketAddress localAddress) throws Exception;
/**
* Disconnect this {@link Channel} from its remote peer
*/
protected abstract void doDisconnect() throws Exception;
/**
* Close the {@link Channel}
*/
protected abstract void doClose() throws Exception;
/**
* Called when conditions justify shutting down the output portion of the channel. This may happen if a write
* operation throws an exception.
*/
@UnstableApi
protected void doShutdownOutput() throws Exception {
doClose();
}
/**
* Deregister the {@link Channel} from its {@link EventLoop}.
*
* Sub-classes may override this method
*/
protected void doDeregister() throws Exception {
// NOOP
}
/**
* Schedule a read operation.
*/
protected abstract void doBeginRead() throws Exception;
/**
* Flush the content of the given buffer to the remote peer.
*/
protected abstract void doWrite(ChannelOutboundBuffer in) throws Exception;
/**
* Invoked when a new message is added to a {@link ChannelOutboundBuffer} of this {@link AbstractChannel}, so that
* the {@link Channel} implementation converts the message to another. (e.g. heap buffer -> direct buffer)
*/
protected Object filterOutboundMessage(Object msg) throws Exception {
return msg;
}
protected void validateFileRegion(DefaultFileRegion region, long position) throws IOException {
DefaultFileRegion.validate(region, position);
}
static final class CloseFuture extends DefaultChannelPromise {
CloseFuture(AbstractChannel ch) {
super(ch);
}
@Override
public ChannelPromise setSuccess() {
throw new IllegalStateException();
}
@Override
public ChannelPromise setFailure(Throwable cause) {
throw new IllegalStateException();
}
@Override
public boolean trySuccess() {
throw new IllegalStateException();
}
@Override
public boolean tryFailure(Throwable cause) {
throw new IllegalStateException();
}
boolean setClosed() {
return super.trySuccess();
}
}
private static final class AnnotatedConnectException extends ConnectException {
private static final long serialVersionUID = 3901958112696433556L;
AnnotatedConnectException(ConnectException exception, SocketAddress remoteAddress) {
super(exception.getMessage() + ": " + remoteAddress);
initCause(exception);
}
// Suppress a warning since this method doesn't need synchronization
@Override
public Throwable fillInStackTrace() { // lgtm[java/non-sync-override]
return this;
}
}
private static final class AnnotatedNoRouteToHostException extends NoRouteToHostException {
private static final long serialVersionUID = -6801433937592080623L;
AnnotatedNoRouteToHostException(NoRouteToHostException exception, SocketAddress remoteAddress) {
super(exception.getMessage() + ": " + remoteAddress);
initCause(exception);
}
// Suppress a warning since this method doesn't need synchronization
@Override
public Throwable fillInStackTrace() { // lgtm[java/non-sync-override]
return this;
}
}
private static final class AnnotatedSocketException extends SocketException {
private static final long serialVersionUID = 3896743275010454039L;
AnnotatedSocketException(SocketException exception, SocketAddress remoteAddress) {
super(exception.getMessage() + ": " + remoteAddress);
initCause(exception);
}
// Suppress a warning since this method doesn't need synchronization
@Override
public Throwable fillInStackTrace() { // lgtm[java/non-sync-override]
return this;
}
}
}