Class UnixLikeTTYTerminal

java.lang.Object

com.googlecode.lanterna.terminal.AbstractTerminal

com.googlecode.lanterna.terminal.ansi.StreamBasedTerminal

com.googlecode.lanterna.terminal.ansi.ANSITerminal

com.googlecode.lanterna.terminal.ansi.UnixLikeTerminal

com.googlecode.lanterna.terminal.ansi.UnixLikeTTYTerminal

All Implemented Interfaces:

Scrollable, InputProvider, ExtendedTerminal, Terminal, Closeable, AutoCloseable

Direct Known Subclasses:

CygwinTerminal, UnixTerminal

public abstract class UnixLikeTTYTerminal
extends UnixLikeTerminal

UnixLikeTerminal extends from ANSITerminal and defines functionality that is common to UnixTerminal and CygwinTerminal, like setting tty modes; echo, cbreak and minimum characters for reading as well as a shutdown hook to set the tty back to original state at the end.

If requested, it handles Control-C input to terminate the program, and hooks into Unix WINCH signal to detect when the user has resized the terminal, if supported by the JVM.

Nested Class Summary

Nested classes/interfaces inherited from class UnixLikeTerminal

UnixLikeTerminal.CtrlCBehaviour

Field Summary

Fields

Modifier and Type	Field	Description
private String	sttyStatusToRestore
private final File	ttyDev

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	UnixLikeTTYTerminal(File ttyDev, InputStream terminalInput, OutputStream terminalOutput, Charset terminalCharset, UnixLikeTerminal.CtrlCBehaviour terminalCtrlCBehaviour)	Creates a UnixTerminal using a specified input stream, output stream and character set, with a custom size querier instead of using the default one.

Method Summary

Modifier and Type	Method	Description
protected void	acquire()	Effectively taking over the terminal and enabling it for Lanterna to use, by turning off echo and canonical mode, adding resize listeners and optionally trap unix signals.
protected void	canonicalMode(boolean enabled)	In canonical mode, data are accumulated in a line editing buffer, and do not become "available for reading" until line editing has been terminated by the user sending a line delimiter character.
protected String	exec(String... cmd)
private String	getSTTYCommand()
protected void	keyEchoEnabled(boolean enabled)	Enables or disable key echo mode, which means when the user press a key, the terminal will immediately print that key to the terminal.
protected void	keyStrokeSignalsEnabled(boolean enabled)	This method causes certain keystrokes (at the moment only ctrl+c) to be passed in to the program as a regular KeyStroke instead of as a signal to the JVM process.
private void	realAcquire()
protected void	registerTerminalResizeListener(Runnable onResize)
protected void	restoreTerminalSettings()	Restores the terminal settings from last time UnixLikeTerminal.saveTerminalSettings() was called
protected String	runSTTYCommand(String... parameters)
protected void	saveTerminalSettings()	Stores the current terminal device settings (the ones that are modified through this interface) so that they can be restored later using UnixLikeTerminal.restoreTerminalSettings()

Methods inherited from class UnixLikeTerminal

close, getTerminalCtrlCBehaviour, pollInput, readInput

Methods inherited from class ANSITerminal

clearScreen, deiconify, disableSGR, enableSGR, enterPrivateMode, exitPrivateMode, findTerminalSize, getCursorPosition, getDefaultKeyDecodingProfile, getTerminalSize, iconify, isInPrivateMode, maximize, popTitle, pushTitle, reportPosition, resetColorAndSGR, restoreCursorPosition, saveCursorPosition, scrollLines, setBackgroundColor, setCursorPosition, setCursorPosition, setCursorVisible, setForegroundColor, setMouseCaptureMode, setTerminalSize, setTitle, unmaximize

Methods inherited from class StreamBasedTerminal

bell, enquireTerminal, flush, getCharset, getInputDecoder, putCharacter, putString, resetMemorizedCursorPosition, translateCharacter, waitForCursorPositionReport, writeToTerminal

Methods inherited from class AbstractTerminal

addResizeListener, newTextGraphics, onResized, onResized, removeResizeListener

Methods inherited from class Object

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

Methods inherited from interface Terminal

addResizeListener, bell, enquireTerminal, flush, newTextGraphics, putCharacter, putString, removeResizeListener

Field Details

ttyDev

private final File ttyDev

sttyStatusToRestore

private String sttyStatusToRestore

Constructor Details

UnixLikeTTYTerminal

protected UnixLikeTTYTerminal(File ttyDev,
 InputStream terminalInput,
 OutputStream terminalOutput,
 Charset terminalCharset,
 UnixLikeTerminal.CtrlCBehaviour terminalCtrlCBehaviour)
                       throws IOException

Creates a UnixTerminal using a specified input stream, output stream and character set, with a custom size querier instead of using the default one. This way you can override size detection (if you want to force the terminal to a fixed size, for example). You also choose how you want ctrl+c key strokes to be handled.

Parameters:

ttyDev - TTY device file that is representing this terminal session, will be used when calling stty to make it operate on this session

terminalInput - Input stream to read terminal input from

terminalOutput - Output stream to write terminal output to

terminalCharset - Character set to use when converting characters to bytes

terminalCtrlCBehaviour - Special settings on how the terminal will behave, see UnixTerminalMode for more details

Throws:

IOException - If there was an I/O error while setting up the terminal

Method Details

acquire

protected void acquire()
                throws IOException

Description copied from class: UnixLikeTerminal

Effectively taking over the terminal and enabling it for Lanterna to use, by turning off echo and canonical mode, adding resize listeners and optionally trap unix signals. This should be called automatically by the constructor of any end-user class extending from UnixLikeTerminal

Overrides:

acquire in class UnixLikeTerminal

Throws:

IOException - If there was an I/O error

realAcquire

private void realAcquire()
                  throws IOException

Throws:

IOException

registerTerminalResizeListener

protected void registerTerminalResizeListener(Runnable onResize)
                                       throws IOException

Specified by:

registerTerminalResizeListener in class UnixLikeTerminal

Throws:

IOException

saveTerminalSettings

protected void saveTerminalSettings()
                             throws IOException

Description copied from class: UnixLikeTerminal

Stores the current terminal device settings (the ones that are modified through this interface) so that they can be restored later using UnixLikeTerminal.restoreTerminalSettings()

Specified by:

saveTerminalSettings in class UnixLikeTerminal

Throws:

IOException - If there was an I/O error when altering the terminal environment

restoreTerminalSettings

protected void restoreTerminalSettings()
                                throws IOException

Description copied from class: UnixLikeTerminal

Restores the terminal settings from last time UnixLikeTerminal.saveTerminalSettings() was called

Specified by:

restoreTerminalSettings in class UnixLikeTerminal

Throws:

IOException - If there was an I/O error when altering the terminal environment

keyEchoEnabled

protected void keyEchoEnabled(boolean enabled)
                       throws IOException

Description copied from class: UnixLikeTerminal

Enables or disable key echo mode, which means when the user press a key, the terminal will immediately print that key to the terminal. Normally for Lanterna, this should be turned off so the software can take the key as an input event, put it on the input queue and then depending on the code decide what to do with it.

Specified by:

keyEchoEnabled in class UnixLikeTerminal

Parameters:

enabled - true if key echo should be enabled, false otherwise

Throws:

IOException - If there was an I/O error when altering the terminal environment

canonicalMode

protected void canonicalMode(boolean enabled)
                      throws IOException

Description copied from class: UnixLikeTerminal

In canonical mode, data are accumulated in a line editing buffer, and do not become "available for reading" until line editing has been terminated by the user sending a line delimiter character. This is usually the default mode for a terminal. Lanterna wants to read each character as they are typed, without waiting for the final newline, so it will attempt to turn canonical mode off on initialization.

Specified by:

canonicalMode in class UnixLikeTerminal

Parameters:

enabled - true if canonical input mode should be enabled, false otherwise

Throws:

IOException - If there was an I/O error when altering the terminal environment

keyStrokeSignalsEnabled

protected void keyStrokeSignalsEnabled(boolean enabled)
                                throws IOException

Description copied from class: UnixLikeTerminal

This method causes certain keystrokes (at the moment only ctrl+c) to be passed in to the program as a regular KeyStroke instead of as a signal to the JVM process. For example, ctrl+c will normally send an interrupt that causes the JVM to shut down, but this method will make it pass in ctrl+c as a regular KeyStroke instead. You can of course still make ctrl+c kill the application through your own input handling if you like.

Please note that this method is called automatically by lanterna to disable signals unless you define a system property "com.googlecode.lanterna.terminal.UnixTerminal.catchSpecialCharacters" and set it to the string "false".

Specified by:

keyStrokeSignalsEnabled in class UnixLikeTerminal

Parameters:

enabled - Pass in true if you want keystrokes to generate system signals (like process interrupt), false if you want lanterna to catch and interpret these keystrokes are regular keystrokes

Throws:

IOException - If there was an I/O error when attempting to disable special characters

See Also:

• UnixLikeTerminal.CtrlCBehaviour

runSTTYCommand

protected String runSTTYCommand(String... parameters)
                         throws IOException

Throws:

IOException

exec

protected String exec(String... cmd)
               throws IOException

Throws:

IOException

getSTTYCommand

private String getSTTYCommand()