org.eclipse.jetty.server.nio

Class SelectChannelConnector

java.lang.Object

org.eclipse.jetty.util.component.AbstractLifeCycle

org.eclipse.jetty.util.component.AggregateLifeCycle

org.eclipse.jetty.server.AbstractConnector

org.eclipse.jetty.server.nio.AbstractNIOConnector

org.eclipse.jetty.server.nio.SelectChannelConnector

All Implemented Interfaces:

HttpBuffers, Connector, NIOConnector, Destroyable, Dumpable, LifeCycle

Direct Known Subclasses:

InheritedChannelConnector, NetworkTrafficSelectChannelConnector, SslSelectChannelConnector

public class SelectChannelConnector
extends AbstractNIOConnector

Selecting NIO connector.

This connector uses efficient NIO buffers with a non blocking threading model. Direct NIO buffers are used and threads are only allocated to connections with requests. Synchronization is used to simulate blocking for the servlet API, and any unflushed content at the end of request handling is written asynchronously.

This connector is best used when there are a many connections that have idle periods.

When used with Continuation, threadless waits are supported. If a filter or servlet returns after calling Continuation.suspend() or when a runtime exception is thrown from a call to Continuation.undispatch(), Jetty will will not send a response to the client. Instead the thread is released and the Continuation is placed on the timer queue. If the Continuation timeout expires, or it's resume method is called, then the request is again allocated a thread and the request is retried. The limitation of this approach is that request content is not available on the retried request, thus if possible it should be read after the continuation or saved as a request attribute or as the associated object of the Continuation instance.

Apache XBean:

element="nioConnector" description="Creates an NIO based socket connector"

Nested Class Summary

Nested classes/interfaces inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

AbstractLifeCycle.AbstractLifeCycleListener

Nested classes/interfaces inherited from interface org.eclipse.jetty.util.component.LifeCycle

LifeCycle.Listener

Field Summary

Fields

Modifier and Type	Field and Description
protected ServerSocketChannel	_acceptChannel

Fields inherited from class org.eclipse.jetty.server.AbstractConnector

_buffers, _lowResourceMaxIdleTime, _maxIdleTime, _soLingerTime

Fields inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

_listeners, FAILED, RUNNING, STARTED, STARTING, STOPPED, STOPPING

Constructor Summary

Constructors

Constructor and Description
SelectChannelConnector() Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	accept(int acceptorID)
void	close()
void	customize(EndPoint endpoint, Request request) Customize a request for an endpoint.
protected void	doStart()
protected void	endPointClosed(SelectChannelEndPoint endpoint)
Object	getConnection()
int	getLocalPort()
int	getLowResourcesConnections()
int	getLowResourcesMaxIdleTime()
SelectorManager	getSelectorManager()
protected AsyncConnection	newConnection(SocketChannel channel, AsyncEndPoint endpoint)
protected SelectChannelEndPoint	newEndPoint(SocketChannel channel, SelectorManager.SelectSet selectSet, SelectionKey key)
void	open() Opens the connector
void	persist(EndPoint endpoint) Persist an endpoint.
void	setLowResourcesConnections(int lowResourcesConnections) Set the number of connections, which if exceeded places this manager in low resources state.
void	setLowResourcesMaxIdleTime(int lowResourcesMaxIdleTime) Set the period in ms that a connection is allowed to be idle when this there are more than getLowResourcesConnections() connections.
void	setMaxIdleTime(int maxIdleTime) Set the maximum Idle time for a connection, which roughly translates to the Socket.setSoTimeout(int) call, although with NIO implementations other mechanisms may be used to implement the timeout.
void	setThreadPool(ThreadPool pool) Set the ThreadPool.

Methods inherited from class org.eclipse.jetty.server.nio.AbstractNIOConnector

getUseDirectBuffers, setUseDirectBuffers

Methods inherited from class org.eclipse.jetty.server.AbstractConnector

checkForwardedHeaders, configure, connectionClosed, connectionOpened, connectionUpgraded, doStop, getAcceptorPriorityOffset, getAcceptors, getAcceptQueueSize, getConfidentialPort, getConfidentialScheme, getConnections, getConnectionsDurationMax, getConnectionsDurationMean, getConnectionsDurationStdDev, getConnectionsDurationTotal, getConnectionsOpen, getConnectionsOpenMax, getConnectionsRequestsMax, getConnectionsRequestsMean, getConnectionsRequestsStdDev, getForwardedCipherSuiteHeader, getForwardedForHeader, getForwardedHostHeader, getForwardedProtoHeader, getForwardedServerHeader, getForwardedSslSessionIdHeader, getHost, getHostHeader, getIntegralPort, getIntegralScheme, getLeftMostFieldValue, getLowResourceMaxIdleTime, getMaxBuffers, getMaxIdleTime, getName, getPort, getRequestBuffers, getRequestBufferSize, getRequestBufferType, getRequestHeaderSize, getRequestHeaderType, getRequests, getResolveNames, getResponseBuffers, getResponseBufferSize, getResponseBufferType, getResponseHeaderSize, getResponseHeaderType, getReuseAddress, getServer, getSoLingerTime, getStatsOn, getStatsOnMs, getThreadPool, isConfidential, isForwarded, isIntegral, isLowResources, join, setAcceptorPriorityOffset, setAcceptors, setAcceptQueueSize, setConfidentialPort, setConfidentialScheme, setForwarded, setForwardedCipherSuiteHeader, setForwardedForHeader, setForwardedHostHeader, setForwardedProtoHeader, setForwardedServerHeader, setForwardedSslSessionIdHeader, setHost, setHostHeader, setIntegralPort, setIntegralScheme, setLowResourceMaxIdleTime, setMaxBuffers, setName, setPort, setRequestBuffers, setRequestBufferSize, setRequestHeaderSize, setResolveNames, setResponseBuffers, setResponseBufferSize, setResponseHeaderSize, setReuseAddress, setServer, setSoLingerTime, setStatsOn, statsReset, stopAccept, toString

Methods inherited from class org.eclipse.jetty.util.component.AggregateLifeCycle

addBean, addBean, contains, destroy, dump, dump, dump, dump, dump, dumpObject, dumpStdErr, dumpThis, getBean, getBeans, getBeans, isManaged, manage, removeBean, removeBeans, unmanage

Methods inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

addLifeCycleListener, getState, getState, isFailed, isRunning, isStarted, isStarting, isStopped, isStopping, removeLifeCycleListener, start, stop

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.eclipse.jetty.util.component.LifeCycle

addLifeCycleListener, isFailed, isRunning, isStarted, isStarting, isStopped, isStopping, removeLifeCycleListener, start, stop

Methods inherited from interface org.eclipse.jetty.util.component.Dumpable

dump, dump

Field Detail

_acceptChannel

protected ServerSocketChannel _acceptChannel

Constructor Detail

SelectChannelConnector

public SelectChannelConnector()

Constructor.

Method Detail

setThreadPool

public void setThreadPool(ThreadPool pool)

Description copied from class: AbstractConnector

Set the ThreadPool. The threadpool passed is added via AggregateLifeCycle.addBean(Object) so that it's lifecycle may be managed as a AggregateLifeCycle.

Overrides:

setThreadPool in class AbstractConnector

Parameters:

pool - the threadPool to set

accept

public void accept(int acceptorID)
            throws IOException

Specified by:

accept in class AbstractConnector

Throws:

IOException

close

public void close()
           throws IOException

Throws:

IOException

customize

public void customize(EndPoint endpoint,
             Request request)
               throws IOException

Description copied from interface: Connector

Customize a request for an endpoint. Called on every request to allow customization of the request for the particular endpoint (eg security properties from a SSL connection).

Specified by:

customize in interface Connector

Overrides:

customize in class AbstractConnector

Throws:

IOException

persist

public void persist(EndPoint endpoint)
             throws IOException

Description copied from interface: Connector

Persist an endpoint. Called after every request if the connection is to remain open.

Specified by:

persist in interface Connector

Overrides:

persist in class AbstractConnector

Throws:

IOException

getSelectorManager

public SelectorManager getSelectorManager()

getConnection

public Object getConnection()

Returns:

the underlying socket, channel, buffer etc. for the connector.

getLocalPort

public int getLocalPort()

Returns:

The actual port the connector is listening on or -1 if it has not been opened, or -2 if it has been closed.

open

public void open()
          throws IOException

Description copied from interface: Connector

Opens the connector

Throws:

IOException

setMaxIdleTime

public void setMaxIdleTime(int maxIdleTime)

Description copied from class: AbstractConnector

Set the maximum Idle time for a connection, which roughly translates to the Socket.setSoTimeout(int) call, although with NIO implementations other mechanisms may be used to implement the timeout. The max idle time is applied:

• When waiting for a new request to be received on a connection
• When reading the headers and content of a request
• When writing the headers and content of a response

Jetty interprets this value as the maximum time between some progress being made on the connection. So if a single byte is read or written, then the timeout (if implemented by jetty) is reset. However, in many instances, the reading/writing is delegated to the JVM, and the semantic is more strictly enforced as the maximum time a single read/write operation can take. Note, that as Jetty supports writes of memory mapped file buffers, then a write may take many 10s of seconds for large content written to a slow device.

Previously, Jetty supported separate idle timeouts and IO operation timeouts, however the expense of changing the value of soTimeout was significant, so these timeouts were merged. With the advent of NIO, it may be possible to again differentiate these values (if there is demand).

Specified by:

setMaxIdleTime in interface Connector

Overrides:

setMaxIdleTime in class AbstractConnector

Parameters:

maxIdleTime - The maxIdleTime to set.

getLowResourcesConnections

public int getLowResourcesConnections()

Returns:

the lowResourcesConnections

setLowResourcesConnections

public void setLowResourcesConnections(int lowResourcesConnections)

Set the number of connections, which if exceeded places this manager in low resources state. This is not an exact measure as the connection count is averaged over the select sets.

Parameters:

lowResourcesConnections - the number of connections

See Also:

setLowResourcesMaxIdleTime(int)

getLowResourcesMaxIdleTime

public int getLowResourcesMaxIdleTime()

Overrides:

getLowResourcesMaxIdleTime in class AbstractConnector

Returns:

the lowResourcesMaxIdleTime

setLowResourcesMaxIdleTime

public void setLowResourcesMaxIdleTime(int lowResourcesMaxIdleTime)

Set the period in ms that a connection is allowed to be idle when this there are more than getLowResourcesConnections() connections. This allows the server to rapidly close idle connections in order to gracefully handle high load situations.

Overrides:

setLowResourcesMaxIdleTime in class AbstractConnector

Parameters:

lowResourcesMaxIdleTime - the period in ms that a connection is allowed to be idle when resources are low.

See Also:

setMaxIdleTime(int)

doStart

protected void doStart()
                throws Exception

Overrides:

doStart in class AbstractConnector

Throws:

Exception

newEndPoint

protected SelectChannelEndPoint newEndPoint(SocketChannel channel,
                                SelectorManager.SelectSet selectSet,
                                SelectionKey key)
                                     throws IOException

Throws:

IOException

endPointClosed

protected void endPointClosed(SelectChannelEndPoint endpoint)

newConnection

protected AsyncConnection newConnection(SocketChannel channel,
                            AsyncEndPoint endpoint)