de.susebox.jtopas

Interface TokenizerPropertyListener

All Known Implementing Classes:

AbstractTokenizer, StandardTokenizer

public interface TokenizerPropertyListener

The interface TokenizerPropertyListener is implemented by classes that are interested in changes in TokenizerProperties objects. Such changes are adding, removing and modifying of properties like keywords, special sequences etc. or parse flags.

Usually, a Tokenizer implementation will also implement this interface. An example is StandardTokenizer. With the listener design pattern, a tokenizer can cache information for fast access that is originally held in its associated TokenizerProperties object, without the danger of using out-of-date data.

The method TokenizerProperties.addTokenizerPropertyListener(de.susebox.jtopas.TokenizerPropertyListener) is used to register a listener. De-registering is done via TokenizerProperties.removeTokenizerPropertyListener(de.susebox.jtopas.TokenizerPropertyListener). The whole mechanism is therefore the same as the event listener schemes used in the AWT or the Swing packages of the JDK.

Author:

Heiko Blau

See Also:

TokenizerProperties, Tokenizer, TokenizerPropertyEvent

Method Summary

Modifier and Type	Method and Description
void	propertyChanged(TokenizerPropertyEvent event) Event handler method.

Method Detail

propertyChanged

void propertyChanged(TokenizerPropertyEvent event)

Event handler method. The given TokenizerPropertyEvent parameter contains the nessecary information about the property change. We choose one single method in favour of various more specialized methods since the reactions on adding, removing and modifying tokenizer properties are often the same (flushing cash, rereading information etc.) or not very different.
A TokenizerProperties object calling its listeners should do this in the order the listeners were registered with the TokenizerProperties.addTokenizerPropertyListener(de.susebox.jtopas.TokenizerPropertyListener) method.

Parameters:

event - the TokenizerPropertyEvent that describes the change