org.crsh.console
Class ProcessHandler

java.lang.Object
  org.crsh.console.Plugin
      org.crsh.console.ProcessHandler

All Implemented Interfaces:

Flushable, InteractionContext, ScreenContext, ShellProcessContext

 class ProcessHandler
extends Plugin
implements ShellProcessContext

A process execution state machine.

Author:

Julien Viet

Nested Class Summary

(package private) class

ProcessHandler.Reader A thread reading a line.

Field Summary

(package private) Console	console .
(package private) AtomicReference<ProcessHandler.Reader>	editor Weather or not a thread is reading a line callback.
(package private) ShellProcess	process .

Constructor Summary

ProcessHandler(Console console, ShellProcess process)

Method Summary

void	end(ShellResponse response) This method is invoked when the process ends.
void	flush()
int	getHeight() Returns the screen height in chars.
String	getProperty(String propertyName) Returns a generic property, usually this property is resolved by the shell client.
int	getWidth() Returns the screen width in chars.
String	readLine(String msg, boolean echo) Display a message and read a line on the console, this method call can be blocking until the user provides a value.
boolean	releaseAlternateBuffer() Release control of the alternate buffer.
boolean	takeAlternateBuffer() Take control of the alternate buffer.
void	write(Chunk chunk) Write a chunk to the screen.

Methods inherited from class java.lang.Object

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

Field Detail

console

final Console console

.

process

final ShellProcess process

.

editor

final AtomicReference<ProcessHandler.Reader> editor

Weather or not a thread is reading a line callback.

Constructor Detail

ProcessHandler

ProcessHandler(Console console,
               ShellProcess process)

Method Detail

takeAlternateBuffer

public boolean takeAlternateBuffer()
                            throws IOException

Description copied from interface: InteractionContext

Take control of the alternate buffer. When the alternate buffer is already used nothing happens. The buffer switch should occur when then Flushable.flush() method is invoked.

Specified by:

takeAlternateBuffer in interface InteractionContext

Returns:

true if the alternate buffer is shown

Throws:

IOException

releaseAlternateBuffer

public boolean releaseAlternateBuffer()
                               throws IOException

Description copied from interface: InteractionContext

Release control of the alternate buffer. When the normal buffer is already used nothing happens. The buffer switch should occur when then Flushable.flush() method is invoked.

Specified by:

releaseAlternateBuffer in interface InteractionContext

Returns:

true if the usual buffer is shown

Throws:

IOException

getProperty

public String getProperty(String propertyName)

Description copied from interface: InteractionContext

Returns a generic property, usually this property is resolved by the shell client.

Specified by:

getProperty in interface InteractionContext

Parameters:

propertyName - the property name

Returns:

the property value

readLine

public String readLine(String msg,
                       boolean echo)
                throws IOException,
                       InterruptedException

Description copied from interface: InteractionContext

Display a message and read a line on the console, this method call can be blocking until the user provides a value. If no line can be read then null is returned.

Specified by:

readLine in interface InteractionContext

Parameters:

msg - the message to display before reading a line

echo - wether or not the line read should be echoed when typing

Returns:

the line read

Throws:

IOException - any io exception

InterruptedException - the thread was interrupted while waiting for the user value

getWidth

public int getWidth()

Description copied from interface: ScreenContext

Returns the screen width in chars. When the value is not positive it means the value could not be determined.

Specified by:

getWidth in interface ScreenContext

Returns:

the term width

getHeight

public int getHeight()

Description copied from interface: ScreenContext

Returns the screen height in chars. When the value is not positive it means the value could not be determined.

Specified by:

getHeight in interface ScreenContext

Returns:

the term height

write

public void write(Chunk chunk)
           throws IOException

Description copied from interface: ScreenContext

Write a chunk to the screen.

Specified by:

write in interface ScreenContext

Parameters:

chunk - the chunk

Throws:

IOException - any io exception

flush

public void flush()
           throws IOException

Specified by:

flush in interface Flushable

Throws:

IOException

end

public void end(ShellResponse response)

Description copied from interface: ShellProcessContext

This method is invoked when the process ends.

Specified by:

end in interface ShellProcessContext

Parameters:

response - the shell response