org.apache.sshd.server.shell

Class InvertedShellWrapper

java.lang.Object

org.apache.sshd.common.util.logging.AbstractLoggingBean

org.apache.sshd.server.shell.InvertedShellWrapper

All Implemented Interfaces:

Command, CommandLifecycle, SessionAware

public class InvertedShellWrapper
extends AbstractLoggingBean
implements Command, SessionAware

A shell implementation that wraps an instance of InvertedShell as a Command. This is useful when using external processes. When starting the shell, this wrapper will also create a thread used to pump the streams and also to check if the shell is alive.

Author:

Apache MINA SSHD Project

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_BUFFER_SIZE Default buffer size for the I/O pumps.
static long	DEFAULT_PUMP_SLEEP_TIME Default value for PUMP_SLEEP_TIME if none set
static String	PUMP_SLEEP_TIME Value used to control the "busy-wait" sleep time (millis) on the pumping loop if nothing was pumped - must be positive

Fields inherited from class org.apache.sshd.common.util.logging.AbstractLoggingBean

log

Constructor Summary

Constructors

Constructor and Description
InvertedShellWrapper(InvertedShell shell) Auto-allocates an Executor in order to create the streams pump thread and uses the DEFAULT_BUFFER_SIZE
InvertedShellWrapper(InvertedShell shell, Executor executor, boolean shutdownExecutor, int bufferSize)
InvertedShellWrapper(InvertedShell shell, int bufferSize) Auto-allocates an Executor in order to create the streams pump thread

Method Summary

Modifier and Type	Method and Description
void	destroy(ChannelSession channel) This method is called by the SSH server to destroy the command because the client has disconnected somehow.
protected boolean	pumpStream(InputStream in, OutputStream out, byte[] buffer)
protected void	pumpStreams()
void	setErrorStream(OutputStream err) Set the error stream that can be used by the shell to write its errors.
void	setExitCallback(ExitCallback callback) Set the callback that the shell has to call when it is closed.
void	setInputStream(InputStream in) Set the input stream that can be used by the shell to read input.
void	setOutputStream(OutputStream out) Set the output stream that can be used by the shell to write its output.
void	setSession(ServerSession session)
void	start(ChannelSession channel, Environment env) Starts the command execution.
String	toString()

Methods inherited from class org.apache.sshd.common.util.logging.AbstractLoggingBean

getSimplifiedLogger

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_BUFFER_SIZE

public static final int DEFAULT_BUFFER_SIZE

Default buffer size for the I/O pumps.

See Also:

Constant Field Values

PUMP_SLEEP_TIME

public static final String PUMP_SLEEP_TIME

Value used to control the "busy-wait" sleep time (millis) on the pumping loop if nothing was pumped - must be positive

See Also:

DEFAULT_PUMP_SLEEP_TIME, Constant Field Values

DEFAULT_PUMP_SLEEP_TIME

public static final long DEFAULT_PUMP_SLEEP_TIME

Default value for PUMP_SLEEP_TIME if none set

See Also:

Constant Field Values

Constructor Detail

InvertedShellWrapper

public InvertedShellWrapper(InvertedShell shell)

Auto-allocates an Executor in order to create the streams pump thread and uses the DEFAULT_BUFFER_SIZE

Parameters:

shell - The InvertedShell

See Also:

InvertedShellWrapper(InvertedShell, int)

InvertedShellWrapper

public InvertedShellWrapper(InvertedShell shell,
                            int bufferSize)

Auto-allocates an Executor in order to create the streams pump thread

Parameters:

shell - The InvertedShell

bufferSize - Buffer size to use - must be above min. size (Byte.SIZE)

See Also:

InvertedShellWrapper(InvertedShell, Executor, boolean, int)

InvertedShellWrapper

public InvertedShellWrapper(InvertedShell shell,
                            Executor executor,
                            boolean shutdownExecutor,
                            int bufferSize)

Parameters:

shell - The InvertedShell

executor - The Executor to use in order to create the streams pump thread. If null one is auto-allocated and shutdown when wrapper is destroy()-ed.

shutdownExecutor - If true the executor is shut down when shell wrapper is destroy()-ed. Ignored if executor service auto-allocated

bufferSize - Buffer size to use - must be above min. size (Byte.SIZE)

Method Detail

setInputStream

public void setInputStream(InputStream in)

Description copied from interface: Command

Set the input stream that can be used by the shell to read input.

Specified by:

setInputStream in interface Command

Parameters:

in - The InputStream used by the shell to read input.

setOutputStream

public void setOutputStream(OutputStream out)

Description copied from interface: Command

Set the output stream that can be used by the shell to write its output.

Specified by:

setOutputStream in interface Command

Parameters:

out - The OutputStream used by the shell to write its output

setErrorStream

public void setErrorStream(OutputStream err)

Description copied from interface: Command

Set the error stream that can be used by the shell to write its errors.

Specified by:

setErrorStream in interface Command

Parameters:

err - The OutputStream used by the shell to write its errors

setExitCallback

public void setExitCallback(ExitCallback callback)

Description copied from interface: Command

Set the callback that the shell has to call when it is closed.

Specified by:

setExitCallback in interface Command

Parameters:

callback - The ExitCallback to call when shell is closed

setSession

public void setSession(ServerSession session)

Specified by:

setSession in interface SessionAware

Parameters:

session - The ServerSession in which this shell will be executed.

start

public void start(ChannelSession channel,
                  Environment env)
           throws IOException

Description copied from interface: CommandLifecycle

Starts the command execution. All streams must have been set before calling this method. The command should implement Runnable, and this method should spawn a new thread like:

  Thread(this).start(); 
 

Specified by:

start in interface CommandLifecycle

Parameters:

channel - The ChannelSession through which the command has been received

env - The Environment

Throws:

IOException - If failed to start

destroy

public void destroy(ChannelSession channel)
             throws Exception

Description copied from interface: CommandLifecycle

This method is called by the SSH server to destroy the command because the client has disconnected somehow.

Specified by:

destroy in interface CommandLifecycle

Parameters:

channel - The ChannelSession through which the command has been received

Throws:

Exception - if failed to destroy

pumpStreams

protected void pumpStreams()

pumpStream

protected boolean pumpStream(InputStream in,
                             OutputStream out,
                             byte[] buffer)
                      throws IOException

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object