ChannelNG (Common API 3.0.4-FINAL API)

java.lang.Object
- com.sshtools.synergy.ssh.ChannelNG<T>

All Implemented Interfaces:

Channel

Direct Known Subclasses:

ForwardingChannel
```
public abstract class ChannelNG<T extends SshContext>
extends java.lang.Object
implements Channel
```
This abstract class provides the basic functions of an SSH2 channel. All terminal sessions, forwarded connections etc, are channels. Either side may open a channel and multiple channels are multiplexed into a single connection. Channels are flow-controlled so that no data may be sent to a channel until a message is received to indicate that a window space is available.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

protected class ChannelNG.ChannelInputStream

Nested Classes
Modifier and Type	Class and Description
`protected class`	`ChannelNG.ChannelInputStream`

Field Summary

Fields
Modifier and Type	Field and Description
`protected CachingDataWindow`	`cache`
`protected SshConnection`	`con`
`protected ConnectionProtocol<T>`	`connection` The Connection Protocol instance managing this session, use this instance to disconnect the session or obtain the ip address of the remote client.
`protected ChannelDataWindow`	`localWindow`
`protected ChannelDataWindow`	`remoteWindow`

Constructor Summary

Constructors
Constructor and Description
`ChannelNG(java.lang.String channelType, int maximumPacketSize, int initialWindowSize, int maximumWindowSpace, int minimumWindowSpace)`
`ChannelNG(java.lang.String channelType, int maximumPacketSize, int initialWindowSize, int maximumWindowSpace, int minimumWindowSpace, ChannelRequestFuture closeFuture, boolean autoConsume)` Construct a channel with the specified settings.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addEventListener(ChannelEventListener listener)` Enable other objects to receive channel events
`protected boolean`	`canClose()` Can this channel close?
`protected boolean`	`checkWindowSpace()`
`void`	`clearIdleState(IdleStateListener listener)` Clear an idle state listener.
`void`	`close()`
`protected void`	`close(boolean forceClose)` This method closes the channel and free's its resources.
`protected CachingDataWindow`	`createCache(int maximumWindowSpace)`
`protected abstract byte[]`	`createChannel()` Called when the channel is being created.
`protected void`	`evaluateWindowSpace()` Called to evaluate the window space available.
`java.lang.String`	`getChannelType()` The name of this channel.
`ChannelRequestFuture`	`getCloseFuture()` Get this channels close future.
`Connection<T>`	`getConnection()`
`ConnectionProtocol<T>`	`getConnectionProtocol()` Returns the `ConnectionProtocol` associated with this channel.
`T`	`getContext()` Get the current configuration from the underlying connection.
`java.io.InputStream`	`getInputStream()`
`long`	`getLastActivity()`
`int`	`getLocalId()` The local channel id
`int`	`getLocalPacket()` The maximum size of a single packet that the local side will accept.
`int`	`getLocalWindow()` The current size of the local data window.
`int`	`getMaxiumRemotePacketSize()`
`int`	`getMaxiumRemoteWindowSize()`
`ChannelRequestFuture`	`getOpenFuture()` Get this channels close future.
`java.io.OutputStream`	`getOutputStream()`
`int`	`getRemoteId()` The remote sides channel id
`int`	`getRemotePacket()` The maximum size of a single packet that the remote side will accept.
`int`	`getRemoteWindow()` The current size of the remote data window.
`java.lang.String`	`getSessionIdentifier()` Get the session id for the current connection.
`int`	`getTimeout()`
`void`	`haltIncomingData()`
`boolean`	`isClosed()` Indicates the channel has been closed
`boolean`	`isClosing()` Indicates whether the channel is currently performing a close operation
`boolean`	`isConnected()`
`boolean`	`isIncomingDataHalted()`
`boolean`	`isLocalEOF()`
`protected boolean`	`isOpen()` Get the open state of the channel.
`boolean`	`isRemoteEOF()`
`protected void`	`log(java.lang.String message)`
`protected void`	`log(java.lang.String action, java.lang.String message)`
`protected void`	`log(java.lang.String message, java.lang.Throwable t)`
`protected void`	`logMessage(java.lang.String message)`
`protected abstract void`	`onChannelClosed()` Called when the channel has been closed to enable resources to be freed.
`protected abstract void`	`onChannelClosing()` Called before the channel is closed
`protected void`	`onChannelData(java.nio.ByteBuffer data)`
`protected void`	`onChannelError(java.lang.Throwable e)`
`protected abstract void`	`onChannelFree()` This method is called when the channel has been closed and all its resources are no longer required.
`protected abstract void`	`onChannelOpen()` Called when the channel has been opened - this method is only called when the remote side requests a channel open.
`protected abstract void`	`onChannelOpenConfirmation()` Called when the channel has been confirmed as open by the remote side - this method is only called when the channel has been requested by this side of the connection
`protected void`	`onChannelOpenFailure()` Called when the remote side fails to open a channel in response to our request.
`protected abstract void`	`onChannelRequest(java.lang.String type, boolean wantreply, byte[] requestdata)` Called when a channel request is received.
`protected void`	`onExtendedData(java.nio.ByteBuffer data, int type)` Called by the channel when extended data arrives
`protected abstract void`	`onLocalEOF()` Called when the local side is EOF.
`protected void`	`onRemoteClose()` Called when the remote side closes the channel.
`protected abstract void`	`onRemoteEOF()` Called when the remote side reports its OutputStream as EOF.
`protected void`	`onWindowAdjust(int count)`
`protected abstract byte[]`	`openChannel(byte[] requestdata)` Called when the channel is being opened.
`protected void`	`processChannelRequestResponse(boolean success)`
`protected void`	`registerExtendedDataType(java.lang.Integer type)`
`void`	`resetIdleState(IdleStateListener listener)` Allows a channel to register and receive idle state events.
`void`	`resumeIncomingData()`
`void`	`sendChannelDataAndBlock(byte[] data)` Send channel data to the remote side of the channel.
`void`	`sendChannelDataAndBlock(byte[] data, int off, int len, java.lang.Runnable r)`
`void`	`sendChannelDataAndBlock(byte[] data, java.lang.Runnable r)`
`void`	`sendChannelDataAndBlock(java.nio.ByteBuffer buf)` Send channel data from a ByteBuffer
`void`	`sendChannelDataAndBlock(java.nio.ByteBuffer buf, int type, java.lang.Runnable r)` Send channel data from a ByteBuffer
`void`	`sendChannelDataAndBlock(java.nio.ByteBuffer buf, java.lang.Runnable r)`
`void`	`sendChannelRequest(java.lang.String type, boolean wantreply, byte[] requestdata)`
`void`	`sendChannelRequest(java.lang.String type, boolean wantreply, byte[] requestdata, ChannelRequestFuture future)` Send a channel request.
`void`	`sendData(byte[] data, int off, int len)`
`void`	`sendEOF()` You can send EOF when you have no more data to send.
`protected void`	`sendExtendedData(byte[] data, int type)` Send extended channel data.
`protected void`	`sendExtendedData(byte[] data, int off, int len, int type)` Send extended channel data.
`protected void`	`sendRequestResponse(boolean succeeded)` Send a channel request.
`protected void`	`sendWindowAdjust()` Adjust the local window by adding more bytes.
`void`	`sendWindowAdjust(int count)`
`void`	`setTimeout(int timeout)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - connection
```
protected ConnectionProtocol<T extends SshContext> connection
```
    The Connection Protocol instance managing this session, use this instance to disconnect the session or obtain the ip address of the remote client.
  - localWindow
```
protected ChannelDataWindow localWindow
```
  - remoteWindow
```
protected ChannelDataWindow remoteWindow
```
  - cache
```
protected CachingDataWindow cache
```
  - con
```
protected SshConnection con
```
- Constructor Detail
  - ChannelNG
```
public ChannelNG(java.lang.String channelType,
                 int maximumPacketSize,
                 int initialWindowSize,
                 int maximumWindowSpace,
                 int minimumWindowSpace,
                 ChannelRequestFuture closeFuture,
                 boolean autoConsume)
```
    Construct a channel with the specified settings.
    
    Parameters:
    
    channelType - the name of the channel, for example "session" or "tcpip-forward"
    
    maximumPacketSize - the maximum size of an individual packet that the remote side can send through the channel
    
    initialWindowSize - the initial size of the local window.
  - ChannelNG
```
public ChannelNG(java.lang.String channelType,
                 int maximumPacketSize,
                 int initialWindowSize,
                 int maximumWindowSpace,
                 int minimumWindowSpace)
```
- Method Detail
  - createCache
```
protected CachingDataWindow createCache(int maximumWindowSpace)
```
  - getInputStream
```
public java.io.InputStream getInputStream()
```
  - getOutputStream
```
public java.io.OutputStream getOutputStream()
```
  - isClosed
```
public boolean isClosed()
```
    Indicates the channel has been closed
    
    Specified by:
    
    isClosed in interface Channel
    
    Returns:
    
    boolean
  - isConnected
```
public boolean isConnected()
```
  - getMaxiumRemoteWindowSize
```
public int getMaxiumRemoteWindowSize()
```
  - getMaxiumRemotePacketSize
```
public int getMaxiumRemotePacketSize()
```
  - resetIdleState
```
public void resetIdleState(IdleStateListener listener)
```
    Allows a channel to register and receive idle state events. Call this method to reset the idle state of a channel (i.e when activity has occurred). The IdleStateListener instance passed as a parameter will receive notification once the channel reaches an idle state. NOTE: It is the callers responsibility to call clearIdleState method to ensure references are released.
    
    Parameters:
    
    listener - IdleStateListener
  - clearIdleState
```
public void clearIdleState(IdleStateListener listener)
```
    Clear an idle state listener.
    
    Parameters:
    
    listener -
  - addEventListener
```
public void addEventListener(ChannelEventListener listener)
```
    Enable other objects to receive channel events
    
    Specified by:
    
    addEventListener in interface Channel
    
    Parameters:
    
    listener -
  - getChannelType
```
public java.lang.String getChannelType()
```
    The name of this channel.
    
    Returns:
    
    String
  - getOpenFuture
```
public ChannelRequestFuture getOpenFuture()
```
    Get this channels close future.
    
    Returns:
  - getCloseFuture
```
public ChannelRequestFuture getCloseFuture()
```
    Get this channels close future.
    
    Returns:
  - getRemoteWindow
```
public int getRemoteWindow()
```
    The current size of the remote data window.
    
    Specified by:
    
    getRemoteWindow in interface Channel
    
    Returns:
    
    int
  - getLocalWindow
```
public int getLocalWindow()
```
    The current size of the local data window.
    
    Specified by:
    
    getLocalWindow in interface Channel
    
    Returns:
    
    int
  - getLocalPacket
```
public int getLocalPacket()
```
    The maximum size of a single packet that the local side will accept.
    
    Specified by:
    
    getLocalPacket in interface Channel
    
    Returns:
    
    int
  - getRemotePacket
```
public int getRemotePacket()
```
    The maximum size of a single packet that the remote side will accept.
    
    Returns:
    
    int
  - getLocalId
```
public int getLocalId()
```
    The local channel id
    
    Returns:
    
    int
  - getRemoteId
```
public int getRemoteId()
```
    The remote sides channel id
    
    Returns:
    
    int
  - getSessionIdentifier
```
public java.lang.String getSessionIdentifier()
```
    Get the session id for the current connection.
    
    Returns:
    
    byte[]
  - registerExtendedDataType
```
protected void registerExtendedDataType(java.lang.Integer type)
```
  - onWindowAdjust
```
protected void onWindowAdjust(int count)
```
  - getLastActivity
```
public long getLastActivity()
```
  - setTimeout
```
public void setTimeout(int timeout)
```
  - getTimeout
```
public int getTimeout()
```
  - getConnection
```
public Connection<T> getConnection()
```
    Specified by:
    
    getConnection in interface Channel
  - getConnectionProtocol
```
public ConnectionProtocol<T> getConnectionProtocol()
```
    Returns the ConnectionProtocol associated with this channel.
    
    Returns:
    
    ConnectionProtocol
  - onChannelData
```
protected void onChannelData(java.nio.ByteBuffer data)
```
  - sendChannelDataAndBlock
```
public void sendChannelDataAndBlock(byte[] data)
                             throws java.io.IOException
```
    Send channel data to the remote side of the channel. The byte array passed into this method will be sent asynchronously so ensure that no other class has access to this after this method returns, failing to do so may cause data corruption.
    
    Parameters:
    
    data -
    
    Throws:
    
    java.io.IOException
  - sendChannelDataAndBlock
```
public void sendChannelDataAndBlock(byte[] data,
                                    java.lang.Runnable r)
                             throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - sendData
```
public void sendData(byte[] data,
                     int off,
                     int len)
              throws java.io.IOException
```
    Specified by:
    
    sendData in interface Channel
    
    Throws:
    
    java.io.IOException
  - sendChannelDataAndBlock
```
public void sendChannelDataAndBlock(byte[] data,
                                    int off,
                                    int len,
                                    java.lang.Runnable r)
                             throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - sendChannelDataAndBlock
```
public void sendChannelDataAndBlock(java.nio.ByteBuffer buf)
                             throws java.io.IOException
```
    Send channel data from a ByteBuffer
    
    Parameters:
    
    buf -
    
    Throws:
    
    java.io.IOException
  - sendChannelDataAndBlock
```
public void sendChannelDataAndBlock(java.nio.ByteBuffer buf,
                                    java.lang.Runnable r)
                             throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - sendChannelDataAndBlock
```
public void sendChannelDataAndBlock(java.nio.ByteBuffer buf,
                                    int type,
                                    java.lang.Runnable r)
                             throws java.io.IOException
```
    Send channel data from a ByteBuffer
    
    Parameters:
    
    buf -
    
    r -
    
    Throws:
    
    java.io.IOException
  - getContext
```
public T getContext()
```
    Get the current configuration from the underlying connection.
    
    Specified by:
    
    getContext in interface Channel
    
    Returns:
    
    ConfigurationContext
  - sendExtendedData
```
protected void sendExtendedData(byte[] data,
                                int type)
                         throws java.io.IOException
```
    Send extended channel data. This data is sent as an extended 'type' which should be known by the channel at the remote side. For example within a session channel an extended data type is used to transfer stderr data from the server to the client.
    
    Parameters:
    
    data -
    
    type -
    
    Throws:
    
    java.io.IOException
  - sendExtendedData
```
protected void sendExtendedData(byte[] data,
                                int off,
                                int len,
                                int type)
                         throws java.io.IOException
```
    Send extended channel data. This data is sent as an extended 'type' which should be known by the channel at the remote side. For example within a session channel an extended data type is used to transfer stderr data from the server to the client.
    
    Parameters:
    
    data -
    
    off -
    
    len -
    
    type -
    
    Throws:
    
    java.io.IOException
  - onExtendedData
```
protected void onExtendedData(java.nio.ByteBuffer data,
                              int type)
```
    Called by the channel when extended data arrives
    
    Parameters:
    
    data -
  - sendChannelRequest
```
public void sendChannelRequest(java.lang.String type,
                               boolean wantreply,
                               byte[] requestdata,
                               ChannelRequestFuture future)
```
    Send a channel request. Many channel types have extensions that are specific to that particular channel type. An example is requresting a pty (pseudo terminal) for an interactive session. This method enables the sending of channel requests but does not support receiving responses. This should not present a problem as server implementations tend to send messages as one way information, for example the exit-status request of an interactive session.
    
    To handle requests from a client implement onChannelRequest(String,boolean,byte[]).
    
    Specified by:
    
    sendChannelRequest in interface Channel
    
    Parameters:
    
    type -
    
    wantreply -
    
    requestdata -
  - sendChannelRequest
```
public void sendChannelRequest(java.lang.String type,
                               boolean wantreply,
                               byte[] requestdata)
```
    Specified by:
    
    sendChannelRequest in interface Channel
  - processChannelRequestResponse
```
protected void processChannelRequestResponse(boolean success)
```
  - onChannelOpenFailure
```
protected void onChannelOpenFailure()
```
    Called when the remote side fails to open a channel in response to our request. It only makes sense for some channel types to override this method. A local forwarding channel will never receive this message for example.
  - onRemoteClose
```
protected void onRemoteClose()
```
    Called when the remote side closes the channel. Override this method to change the default behaviour of instantly closing the channel unless there is buffered data remaining
  - isClosing
```
public boolean isClosing()
```
    Indicates whether the channel is currently performing a close operation
    
    Returns:
    
    boolean
  - close
```
public void close()
```
    Specified by:
    
    close in interface Channel
  - close
```
protected void close(boolean forceClose)
```
    This method closes the channel and free's its resources.
  - onChannelFree
```
protected abstract void onChannelFree()
```
    This method is called when the channel has been closed and all its resources are no longer required.
  - createChannel
```
protected abstract byte[] createChannel()
                                 throws java.io.IOException
```
    Called when the channel is being created. You can return data to be sent in the channel open request, or null for none.
    
    Returns:
    
    byte[]
    
    Throws:
    
    java.io.IOException
  - openChannel
```
protected abstract byte[] openChannel(byte[] requestdata)
                               throws WriteOperationRequest,
                                      ChannelOpenException
```
    Called when the channel is being opened. You can retrun data to be sent in the channel open confirmation message, or null for none.
    
    Parameters:
    
    requestdata -
    
    Returns:
    
    byte[]
    
    Throws:
    
    WriteOperationRequest
    
    ChannelOpenException
  - onChannelOpenConfirmation
```
protected abstract void onChannelOpenConfirmation()
```
    Called when the channel has been confirmed as open by the remote side - this method is only called when the channel has been requested by this side of the connection
  - onChannelClosed
```
protected abstract void onChannelClosed()
```
    Called when the channel has been closed to enable resources to be freed.
  - onChannelOpen
```
protected abstract void onChannelOpen()
```
    Called when the channel has been opened - this method is only called when the remote side requests a channel open.
  - onChannelClosing
```
protected abstract void onChannelClosing()
```
    Called before the channel is closed
  - onChannelRequest
```
protected abstract void onChannelRequest(java.lang.String type,
                                         boolean wantreply,
                                         byte[] requestdata)
```
    Called when a channel request is received.
    
    Parameters:
    
    type -
    
    wantreply -
    
    requestdata -
  - evaluateWindowSpace
```
protected void evaluateWindowSpace()
```
    Called to evaluate the window space available. Send a window adjust message if there if the minimum amount of space is not available.
    
    Parameters:
    
    remaining -
  - onRemoteEOF
```
protected abstract void onRemoteEOF()
```
    Called when the remote side reports its OutputStream as EOF.
  - sendEOF
```
public void sendEOF()
```
    You can send EOF when you have no more data to send. The channel will still remain open until a close message is received.
  - canClose
```
protected boolean canClose()
```
    Can this channel close?
    
    Returns:
    
    true if there is no queued data, else false
  - onLocalEOF
```
protected abstract void onLocalEOF()
```
    Called when the local side is EOF.
  - isOpen
```
protected boolean isOpen()
```
    Get the open state of the channel.
    
    Returns:
    
    boolean
  - sendRequestResponse
```
protected void sendRequestResponse(boolean succeeded)
```
    Send a channel request.
    
    Parameters:
    
    succeeded -
  - sendWindowAdjust
```
protected void sendWindowAdjust()
```
    Adjust the local window by adding more bytes.
    
    Parameters:
    
    count -
  - sendWindowAdjust
```
public void sendWindowAdjust(int count)
```
    Specified by:
    
    sendWindowAdjust in interface Channel
  - logMessage
```
protected void logMessage(java.lang.String message)
```
  - log
```
protected void log(java.lang.String action,
                   java.lang.String message)
```
  - log
```
protected void log(java.lang.String message)
```
  - log
```
protected void log(java.lang.String message,
                   java.lang.Throwable t)
```
  - isLocalEOF
```
public boolean isLocalEOF()
```
    Specified by:
    
    isLocalEOF in interface Channel
  - isRemoteEOF
```
public boolean isRemoteEOF()
```
    Specified by:
    
    isRemoteEOF in interface Channel
  - isIncomingDataHalted
```
public boolean isIncomingDataHalted()
```
  - haltIncomingData
```
public void haltIncomingData()
```
  - resumeIncomingData
```
public void resumeIncomingData()
```
  - checkWindowSpace
```
protected boolean checkWindowSpace()
```
  - onChannelError
```
protected void onChannelError(java.lang.Throwable e)
```

Class ChannelNG<T extends SshContext>

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

connection

localWindow

remoteWindow

cache

con

Constructor Detail

ChannelNG

ChannelNG

Method Detail

createCache

getInputStream

getOutputStream

isClosed

isConnected

getMaxiumRemoteWindowSize

getMaxiumRemotePacketSize

resetIdleState

clearIdleState

addEventListener

getChannelType

getOpenFuture

getCloseFuture

getRemoteWindow

getLocalWindow

getLocalPacket

getRemotePacket

getLocalId

getRemoteId

getSessionIdentifier

registerExtendedDataType

onWindowAdjust

getLastActivity

setTimeout

getTimeout

getConnection

getConnectionProtocol

onChannelData

sendChannelDataAndBlock

sendChannelDataAndBlock

sendData

sendChannelDataAndBlock

sendChannelDataAndBlock

sendChannelDataAndBlock

sendChannelDataAndBlock

getContext

sendExtendedData

sendExtendedData

onExtendedData

sendChannelRequest

sendChannelRequest

processChannelRequestResponse

onChannelOpenFailure

onRemoteClose

isClosing

close

close

onChannelFree

createChannel

openChannel

onChannelOpenConfirmation

onChannelClosed

onChannelOpen

onChannelClosing

onChannelRequest

evaluateWindowSpace

onRemoteEOF

sendEOF

canClose

onLocalEOF

isOpen

sendRequestResponse

sendWindowAdjust

sendWindowAdjust