org.eclipse.jetty.io.SelectableChannelEndPoint Maven / Gradle / Ivy
//
// ========================================================================
// Copyright (c) 1995 Mort Bay Consulting Pty Ltd and others.
//
// This program and the accompanying materials are made available under the
// terms of the Eclipse Public License v. 2.0 which is available at
// https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
// which is available at https://www.apache.org/licenses/LICENSE-2.0.
//
// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
// ========================================================================
//
package org.eclipse.jetty.io;
import java.io.Closeable;
import java.net.SocketAddress;
import java.nio.channels.CancelledKeyException;
import java.nio.channels.NetworkChannel;
import java.nio.channels.SelectableChannel;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import org.eclipse.jetty.util.IO;
import org.eclipse.jetty.util.thread.AutoLock;
import org.eclipse.jetty.util.thread.Invocable;
import org.eclipse.jetty.util.thread.Scheduler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A partial {@link EndPoint} implementation based on {@link SelectableChannel}.
*/
public abstract class SelectableChannelEndPoint extends AbstractEndPoint implements ManagedSelector.Selectable
{
private static final Logger LOG = LoggerFactory.getLogger(SelectableChannelEndPoint.class);
private final AutoLock _lock = new AutoLock();
private final SelectableChannel _channel;
private final ManagedSelector _selector;
private SelectionKey _key;
private boolean _updatePending;
// The current value for interestOps.
private int _currentInterestOps;
// The desired value for interestOps.
private int _desiredInterestOps;
private final ManagedSelector.SelectorUpdate _updateKeyAction = this::updateKeyAction;
private final Runnable _runFillable = new RunnableCloseable("runFillable")
{
@Override
public void run()
{
getFillInterest().fillable();
}
@Override
public InvocationType getInvocationType()
{
return getFillInterest().getCallbackInvocationType();
}
};
private final Runnable _runCompleteWrite = new RunnableCloseable("runCompleteWrite")
{
@Override
public void run()
{
getWriteFlusher().completeWrite();
}
@Override
public InvocationType getInvocationType()
{
return getWriteFlusher().getCallbackInvocationType();
}
@Override
public String toString()
{
return String.format("%s:%s:%s->%s", SelectableChannelEndPoint.this, _operation, getInvocationType(), getWriteFlusher());
}
};
private final Runnable _runCompleteWriteFillable = new RunnableCloseable("runCompleteWriteFillable")
{
@Override
public void run()
{
getWriteFlusher().completeWrite();
getFillInterest().fillable();
}
@Override
public InvocationType getInvocationType()
{
InvocationType fillT = getFillInterest().getCallbackInvocationType();
InvocationType flushT = getWriteFlusher().getCallbackInvocationType();
if (fillT == flushT)
return fillT;
if (fillT == InvocationType.EITHER && flushT == InvocationType.NON_BLOCKING)
return InvocationType.EITHER;
if (fillT == InvocationType.NON_BLOCKING && flushT == InvocationType.EITHER)
return InvocationType.EITHER;
return InvocationType.BLOCKING;
}
};
public SelectableChannelEndPoint(Scheduler scheduler, SelectableChannel channel, ManagedSelector selector, SelectionKey selectionKey)
{
super(scheduler);
_channel = channel;
_selector = selector;
_key = selectionKey;
}
public SelectableChannel getChannel()
{
return _channel;
}
@Override
public Object getTransport()
{
return getChannel();
}
@Override
public SocketAddress getLocalSocketAddress()
{
try
{
SelectableChannel channel = getChannel();
if (channel instanceof NetworkChannel)
return ((NetworkChannel)channel).getLocalAddress();
return super.getLocalSocketAddress();
}
catch (Throwable x)
{
LOG.trace("Could not retrieve local socket address", x);
return null;
}
}
@Override
public boolean isOpen()
{
return _channel.isOpen();
}
@Override
public void doClose()
{
if (LOG.isDebugEnabled())
LOG.debug("doClose {}", this);
IO.close(_channel);
super.doClose();
}
@Override
public void onClose(Throwable cause)
{
try
{
super.onClose(cause);
}
finally
{
if (_selector != null)
_selector.destroyEndPoint(this, cause);
}
}
@Override
protected void needsFillInterest()
{
changeInterests(SelectionKey.OP_READ);
}
@Override
protected void onIncompleteFlush()
{
changeInterests(SelectionKey.OP_WRITE);
}
private void changeInterests(int operation)
{
// This method runs from any thread, possibly
// concurrently with updateKey() and onSelected().
int oldInterestOps;
int newInterestOps;
boolean pending;
try (AutoLock l = _lock.lock())
{
pending = _updatePending;
oldInterestOps = _desiredInterestOps;
newInterestOps = oldInterestOps | operation;
if (newInterestOps != oldInterestOps)
_desiredInterestOps = newInterestOps;
}
if (LOG.isDebugEnabled())
LOG.debug("changeInterests p={} {}->{} for {}", pending, oldInterestOps, newInterestOps, this);
if (!pending && _selector != null)
_selector.submit(_updateKeyAction);
}
@Override
public Runnable onSelected()
{
// This method runs from the selector thread,
// possibly concurrently with changeInterests(int).
int readyOps = _key.readyOps();
int oldInterestOps;
int newInterestOps;
try (AutoLock l = _lock.lock())
{
_updatePending = true;
// Remove the readyOps, that here can only be OP_READ or OP_WRITE (or both).
oldInterestOps = _desiredInterestOps;
newInterestOps = oldInterestOps & ~readyOps;
_desiredInterestOps = newInterestOps;
}
boolean fillable = (readyOps & SelectionKey.OP_READ) != 0;
boolean flushable = (readyOps & SelectionKey.OP_WRITE) != 0;
if (LOG.isDebugEnabled())
LOG.debug("onSelected {}->{} r={} w={} for {}", oldInterestOps, newInterestOps, fillable, flushable, this);
// return task to complete the job
Runnable task = fillable
? (flushable
? _runCompleteWriteFillable
: _runFillable)
: (flushable
? _runCompleteWrite
: null);
if (LOG.isDebugEnabled())
LOG.debug("task {}", task);
return task;
}
private void updateKeyAction(Selector selector)
{
updateKey();
}
@Override
public void updateKey()
{
// This method runs from the selector thread,
// possibly concurrently with changeInterests(int).
try
{
int oldInterestOps;
int newInterestOps;
try (AutoLock l = _lock.lock())
{
_updatePending = false;
oldInterestOps = _currentInterestOps;
newInterestOps = _desiredInterestOps;
if (oldInterestOps != newInterestOps)
{
_currentInterestOps = newInterestOps;
_key.interestOps(newInterestOps);
}
}
if (LOG.isDebugEnabled())
LOG.debug("Key interests updated {} -> {} on {}", oldInterestOps, newInterestOps, this);
}
catch (CancelledKeyException x)
{
if (LOG.isDebugEnabled())
LOG.debug("Ignoring key update for cancelled key {}", this, x);
close();
}
catch (Throwable x)
{
LOG.warn("Ignoring key update for {}", this, x);
close();
}
}
@Override
public void replaceKey(SelectionKey newKey)
{
_key = newKey;
}
@Override
public String toEndPointString()
{
// We do a best effort to print the right toString() and that's it.
return String.format("%s{io=%d/%d,kio=%d,kro=%d}",
super.toEndPointString(),
_currentInterestOps,
_desiredInterestOps,
ManagedSelector.safeInterestOps(_key),
ManagedSelector.safeReadyOps(_key));
}
private abstract class RunnableCloseable implements Invocable.Task, Closeable
{
final String _operation;
private RunnableCloseable(String operation)
{
_operation = operation;
}
@Override
public void close()
{
try
{
SelectableChannelEndPoint.this.close();
}
catch (Throwable x)
{
LOG.warn("Unable to close {}", SelectableChannelEndPoint.this, x);
}
}
@Override
public String toString()
{
return String.format("%s:%s:%s", SelectableChannelEndPoint.this, _operation, getInvocationType());
}
}
}