org.snf4j.example.engine

Class AbstractEngine

java.lang.Object

org.snf4j.example.engine.AbstractEngine

All Implemented Interfaces:

IEngine

Direct Known Subclasses:

BasicEngine

public abstract class AbstractEngine
extends Object
implements IEngine

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	AbstractEngine.CloseType

Field Summary

Fields

Modifier and Type	Field and Description
protected HandshakeStatus	handshakeStatus
protected AbstractEngine.CloseType	inboundDone
protected AbstractEngine.CloseType	outboundDone

Constructor Summary

Constructors

Constructor and Description
AbstractEngine()

Method Summary

Modifier and Type	Method and Description
void	beginHandshake() Initiates handshaking on this IEngine implementation.
void	cleanup() Signals that an IEngine implementation can cleanup, if required, its internal state (e.g.
void	closeInbound() Signals that no more inbound network data will be sent to an IEngine implementation.
void	closeOutbound() Signals that no more outbound application data will be sent to an IEngine implementation.
Runnable	getDelegatedTask() Returns a delegated Runnable task for an IEngine implementation.
HandshakeStatus	getHandshakeStatus() Returns the current handshake status for an IEngine implementation.
int	getMaxApplicationBufferSize() Gets the current maximum size of the buffer holding application data
int	getMaxNetworkBufferSize() Gets the current maximum size of the buffer holding network data
int	getMinApplicationBufferSize() Gets the current minimum size of the buffer holding application data.
int	getMinNetworkBufferSize() Gets the current minimum size of the buffer holding network data.
Object	getSession() Returns an object representing a session in use in an IEngine implementation.
void	init() Signals that an IEngine implementation can initialize, if required, its internal state (e.g.
boolean	isInboundDone() Returns whether IEngine.unwrap(ByteBuffer, ByteBuffer) method will accept any more inbound network data.
boolean	isOutboundDone() Returns whether IEngine.wrap(ByteBuffer, ByteBuffer) and IEngine.wrap(ByteBuffer[], ByteBuffer) methods will produce any more outbound network data.
protected IEngineResult	updateHandshakeStatus(IEngineResult result)
IEngineResult	wrap(ByteBuffer src, ByteBuffer dst) Attempts to encode outbound application data from a data buffer into outbound network data.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.snf4j.core.engine.IEngine

unwrap, wrap

Field Detail

outboundDone

protected AbstractEngine.CloseType outboundDone

inboundDone

protected AbstractEngine.CloseType inboundDone

handshakeStatus

protected HandshakeStatus handshakeStatus

Constructor Detail

AbstractEngine

public AbstractEngine()

Method Detail

init

public void init()

Description copied from interface: IEngine

Signals that an IEngine implementation can initialize, if required, its internal state (e.g. allocate required resources). It is called during pre-creation phase of an engine driven session (i.e. before the event SessionEvent.CREATED is signaled to the session handler).

Specified by:

init in interface IEngine

cleanup

public void cleanup()

Description copied from interface: IEngine

Signals that an IEngine implementation can cleanup, if required, its internal state (e.g. release allocated resources). It is called during post-ending phase of an engine driven session (i.e. after the event SessionEvent.ENDING is fully processed by the session handler).

Specified by:

cleanup in interface IEngine

beginHandshake

public void beginHandshake()
                    throws Exception

Description copied from interface: IEngine

Initiates handshaking on this IEngine implementation. This method is not called by the SNF4J framework for a initial handshake, as the initial handshake should be initiated by the wrap() and unwrap() methods when they are called for the first time.

This method is never called by the SNF4J framework when another handshake is still in progress on this engine. Any try to begin a new handshake from an engine stream session will be silently ignored unless previously started handshake is finished. The finishing is signaled by the HandshakeStatus.FINISHED status returned by the wrap or unwrap method.

Specified by:

beginHandshake in interface IEngine

Throws:

Exception - if a problem was encountered while signaling the beginning of a new handshake.

getSession

public Object getSession()

Description copied from interface: IEngine

Returns an object representing a session in use in an IEngine implementation.

Specified by:

getSession in interface IEngine

Returns:

an object representing a session.

isOutboundDone

public boolean isOutboundDone()

Description copied from interface: IEngine

Returns whether IEngine.wrap(ByteBuffer, ByteBuffer) and IEngine.wrap(ByteBuffer[], ByteBuffer) methods will produce any more outbound network data.

Specified by:

isOutboundDone in interface IEngine

Returns:

true if an IEngine implementation will not produce any more network data

isInboundDone

public boolean isInboundDone()

Description copied from interface: IEngine

Returns whether IEngine.unwrap(ByteBuffer, ByteBuffer) method will accept any more inbound network data.

Specified by:

isInboundDone in interface IEngine

Returns:

true if an IEngine implementation will not consume anymore network data

See Also:

IEngine.closeInbound()

closeOutbound

public void closeOutbound()

Description copied from interface: IEngine

Signals that no more outbound application data will be sent to an IEngine implementation.

This method should be idempotent: if the outbound side has already been closed, this method should not do anything.

Specified by:

closeOutbound in interface IEngine

See Also:

IEngine.isOutboundDone()

closeInbound

public void closeInbound()
                  throws SessionIncidentException

Description copied from interface: IEngine

Signals that no more inbound network data will be sent to an IEngine implementation.

This method should be idempotent: if the inbound side has already been closed, this method should not do anything.

Specified by:

closeInbound in interface IEngine

Throws:

SessionIncidentException - if this engine implementation detected an incident that should be reported to the associated session's handler (e.g. when an engine has not received a proper close message from the peer).

See Also:

IEngine.isInboundDone()

getMinApplicationBufferSize

public int getMinApplicationBufferSize()

Description copied from interface: IEngine

Gets the current minimum size of the buffer holding application data. An IEngine implementation may use application data (i.e. the application data wrapped in one network packet) of any size up to and including the value returned by this method.

Specified by:

getMinApplicationBufferSize in interface IEngine

Returns:

the minimum buffer size

getMinNetworkBufferSize

public int getMinNetworkBufferSize()

Description copied from interface: IEngine

Gets the current minimum size of the buffer holding network data. An IEngine implementation may generate network packets of any size up to and including the value returned by this method.

Specified by:

getMinNetworkBufferSize in interface IEngine

Returns:

the minimum buffer size

getMaxApplicationBufferSize

public int getMaxApplicationBufferSize()

Description copied from interface: IEngine

Gets the current maximum size of the buffer holding application data

This method is only used by the EngineStreamSession class.

Specified by:

getMaxApplicationBufferSize in interface IEngine

Returns:

the maximum buffer size

getMaxNetworkBufferSize

public int getMaxNetworkBufferSize()

Description copied from interface: IEngine

Gets the current maximum size of the buffer holding network data

This method is only used by the EngineStreamSession class.

Specified by:

getMaxNetworkBufferSize in interface IEngine

Returns:

the maximum buffer size

getHandshakeStatus

public HandshakeStatus getHandshakeStatus()

Description copied from interface: IEngine

Returns the current handshake status for an IEngine implementation.

It should never return the FINISHED status.

Specified by:

getHandshakeStatus in interface IEngine

Returns:

the current handshake status

getDelegatedTask

public Runnable getDelegatedTask()

Description copied from interface: IEngine

Returns a delegated Runnable task for an IEngine implementation.

IEngine operations may require the results of operations that block, or may take an extended period of time to complete. This method should be used to obtain a pending Runnable operation (task). Each task will be assigned a thread to perform the run operation. The assigned thread will be created by a thread factory configured in the selector loop that will handle the session associated with this IEngine implementation.

A call to this method should return each pending task exactly once.

Multiple tasks can be run in parallel.

Specified by:

getDelegatedTask in interface IEngine

Returns:

a pending Runnable, task, or null if none are available.

wrap

public IEngineResult wrap(ByteBuffer src,
                          ByteBuffer dst)
                   throws Exception

Description copied from interface: IEngine

Attempts to encode outbound application data from a data buffer into outbound network data.

Depending on the state of an IEngine implementation, this method can produce network data without consuming any application data (for example, it may generate handshake data.)

If an IEngine implementation has not yet started its initial handshake, this method should automatically start the handshake.

Specified by:

wrap in interface IEngine

Parameters:

src - a ByteBuffer containing the outbound application data

dst - a ByteBuffer to hold outbound network data

Returns:

an EngineResult describing the result of this operation.

Throws:

Exception - when a problem occurred. Once it is thrown the associated session will be quickly closed

updateHandshakeStatus

protected IEngineResult updateHandshakeStatus(IEngineResult result)