org.extex.main.tex
Class ErrorHandlerImpl

java.lang.Object
  org.extex.main.tex.ErrorHandlerImpl

All Implemented Interfaces:

LogEnabled, ErrorHandler

Direct Known Subclasses:

ErrorHandlerTeXImpl

public class ErrorHandlerImpl
extends java.lang.Object
implements ErrorHandler, LogEnabled

This is a simple implementation of the error handler interacting with the user on the command line like TeX does.

The HelpingException is capable of carrying a name and two arguments for the error message. This class can be queried to provide additional help concerning the error at hand. See HelpingException for details.

Version:

$Revision: 6447 $

Author:

Gerd Neugebauer

Field Summary

protected static java.lang.String

NL The constant NL contains the String with the newline character, since it is needed several times.

Constructor Summary

ErrorHandlerImpl()
Creates a new object.

Method Summary

void	enableLogging(java.util.logging.Logger theLogger) Setter for the logger.
protected void	handleDebug() Special treatment of the debug case.
boolean	handleError(GeneralException exception, Token t, TokenSource source, Context context) This is the error handling callback.
protected java.lang.String	promptAndReadLine(java.lang.String prompt) Read a line of characters from the standard input stream after a prompt has been shown.
void	setEditHandler(EditHandler editHandler) Setter for the edit handler.
protected void	showErrorLine(java.util.logging.Logger logger, java.lang.String message, Locator locator) This method is invoked to present the current line causing the error.

Methods inherited from class java.lang.Object

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

Field Detail

NL

protected static final java.lang.String NL

The constant NL contains the String with the newline character, since it is needed several times.

See Also:

Constant Field Values

Constructor Detail

ErrorHandlerImpl

public ErrorHandlerImpl()

Creates a new object.

Method Detail

enableLogging

public void enableLogging(java.util.logging.Logger theLogger)

Setter for the logger.

Specified by:

enableLogging in interface LogEnabled

Parameters:

theLogger - the logger to use

See Also:

LogEnabled.enableLogging( java.util.logging.Logger)

handleDebug

protected void handleDebug()
                    throws HelpingException

Special treatment of the debug case. This method is meant to be redefined to provide additional functionality.

Throws:

HelpingException - in case of EOF on terminal

See Also:

"TTP[1338]"

handleError

public boolean handleError(GeneralException exception,
                           Token t,
                           TokenSource source,
                           Context context)
                    throws HelpingException

This is the error handling callback.

Specified by:

handleError in interface ErrorHandler

Parameters:

exception - the exception which has led to the invocation

t - the token leading to the error

source - the token source

context - the processor context

Returns:

true iff the processing can continue

Throws:

HelpingException - in case of en error

See Also:

ErrorHandler.handleError(org.extex.core.exception.GeneralException, org.extex.scanner.type.token.Token, org.extex.interpreter.TokenSource, org.extex.interpreter.context.Context)

promptAndReadLine

protected java.lang.String promptAndReadLine(java.lang.String prompt)
                                      throws HelpingException

Read a line of characters from the standard input stream after a prompt has been shown. Leading spaces are ignored. At end of file an exception is thrown.

Parameters:

prompt - the prompt to display

Returns:

the line read or null to signal EOF

Throws:

HelpingException - in case of EOF on terminal

setEditHandler

public void setEditHandler(EditHandler editHandler)

Setter for the edit handler.

Specified by:

setEditHandler in interface ErrorHandler

Parameters:

editHandler - the new edit handler

See Also:

ErrorHandler.setEditHandler( org.extex.interpreter.EditHandler)

showErrorLine

protected void showErrorLine(java.util.logging.Logger logger,
                             java.lang.String message,
                             Locator locator)

This method is invoked to present the current line causing the error.

Parameters:

logger - the logger to use for output

message - the error message

locator - the locator for the error position