net.digger.util.vt

Class VTParser

java.lang.Object

net.digger.util.vt.VTParser

All Implemented Interfaces:

net.digger.util.fsm.ActionHandler<Action,State,Character>

public class VTParser
extends Object
implements net.digger.util.fsm.ActionHandler<Action,State,Character>

VT/ANSI parser.

This class parses text for escape sequences, and runs the caller-provided callback with the details of each sequence. That callback will need to implement whichever sequences it chooses to support.

Implements Paul Flo Williams' state machine (https://vt100.net/emu/dec_ansi_parser). Loosely based on Joshua Haberman's vtparse (https://github.com/haberman/vtparse).

Author:

walton

Constructor Summary

Constructors

Constructor and Description
VTParser(VTEmulator emulator) Create a new instance of VTParser, and provide a VTEmulator implementation.
VTParser(VTEmulator emulator, boolean use7bits) Create a new instance of VTParser using only 7-bit transitions, and provide a VTEmulator implementation.

Method Summary

Modifier and Type	Method and Description
static void	main(String[] args) Test program, parses text from STDIN.
void	onEntry(State state, Action action)
void	onEvent(State state, Character event, Action action)
void	onExit(State state, Action action)
void	parse(char ch) Process a character.
void	parse(String str) Process a string.
static String	stripString(String text, boolean use7bits) Returns the given text with all escape sequences stripped out of it.

Methods inherited from class java.lang.Object

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

Constructor Detail

VTParser

public VTParser(VTEmulator emulator)

Create a new instance of VTParser, and provide a VTEmulator implementation.

Event values 0xA0-0xFF are treated as 0x20-0x7F and values above 0xFF are treated as 0x7F.

Parameters:

emulator - VTEmulator implementation called when an escape sequence is parsed.

VTParser

public VTParser(VTEmulator emulator,
                boolean use7bits)

Create a new instance of VTParser using only 7-bit transitions, and provide a VTEmulator implementation. If use7bits=true, event values above 0x7F are treated as 0x7F. This avoids the special handling of 0x80-0x9f, when working with a character set (such as CP-437) where those are printable. Otherwise, values 0xA0-0xFF are treated as 0x20-0x7F and values above 0xFF are treated as 0x7F.

Parameters:

emulator - VTEmulator implementation called when an escape sequence is parsed.

use7bits - Flag to process the text as 7-bit ASCII instead of 8-bit.

Method Detail

parse

public void parse(char ch)

Process a character.

Parameters:

ch - Character to process.

parse

public void parse(String str)

Process a string.

Parameters:

str - String to process.

stripString

public static String stripString(String text,
                                 boolean use7bits)

Returns the given text with all escape sequences stripped out of it. If use7bits=true, event values above 0x7F are treated as 0x7F. This avoids the special handling of 0x80-0x9f, when working with a character set (such as CP-437) where those are printable. Otherwise, values 0xA0-0xFF are treated as 0x20-0x7F and values above 0xFF are treated as 0x7F.

Parameters:

text - Text to process.

use7bits - Flag to process the text as 7-bit ASCII instead of 8-bit.

Returns:

Text with all escape sequences removed.

onEntry

public void onEntry(State state,
                    Action action)

Specified by:

onEntry in interface net.digger.util.fsm.ActionHandler<Action,State,Character>

onEvent

public void onEvent(State state,
                    Character event,
                    Action action)

Specified by:

onEvent in interface net.digger.util.fsm.ActionHandler<Action,State,Character>

onExit

public void onExit(State state,
                   Action action)

Specified by:

onExit in interface net.digger.util.fsm.ActionHandler<Action,State,Character>

main

public static void main(String[] args)

Test program, parses text from STDIN.

Parameters:

args - Command-line arguments for test program.