opennlp.tools.sentdetect
Class DefaultSDContextGenerator

java.lang.Object
  opennlp.tools.sentdetect.DefaultSDContextGenerator

All Implemented Interfaces:

SDContextGenerator

Direct Known Subclasses:

SentenceContextGenerator

public class DefaultSDContextGenerator
extends java.lang.Object
implements SDContextGenerator

Generate event contexts for maxent decisions for sentence detection.

Version:

$Revision: 1.1 $, $Date: 2008/03/05 16:45:13 $

Author:

Jason Baldridge, Eric D. Friedman

Field Summary

protected java.lang.StringBuffer	buf String buffer for generating features.
protected java.util.List	collectFeats List for holding features as they are generated.

Constructor Summary

DefaultSDContextGenerator(char[] eosCharacters)
Creates a new SDContextGenerator instance with no induced abbreviations.

DefaultSDContextGenerator(java.util.Set inducedAbbreviations, char[] eosCharacters)
Creates a new SDContextGenerator instance which uses the set of induced abbreviations.

Method Summary

protected void	collectFeatures(java.lang.String prefix, java.lang.String suffix, java.lang.String previous, java.lang.String next) Determines some of the features for the sentence detector and adds them to list features.
java.lang.String[]	getContext(java.lang.StringBuffer sb, int position) Returns an array of contextual features for the potential sentence boundary at the specified position within the specified string buffer.

Methods inherited from class java.lang.Object

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

Field Detail

buf

protected java.lang.StringBuffer buf

String buffer for generating features.

collectFeats

protected java.util.List collectFeats

List for holding features as they are generated.

Constructor Detail

DefaultSDContextGenerator

public DefaultSDContextGenerator(char[] eosCharacters)

Creates a new SDContextGenerator instance with no induced abbreviations.

Parameters:

eosCharacters -

DefaultSDContextGenerator

public DefaultSDContextGenerator(java.util.Set inducedAbbreviations,
                                 char[] eosCharacters)

Creates a new SDContextGenerator instance which uses the set of induced abbreviations.

Parameters:

inducedAbbreviations - a Set of Strings representing induced abbreviations in the training data. Example: "Mr."

eosCharacters -

Method Detail

getContext

public java.lang.String[] getContext(java.lang.StringBuffer sb,
                                     int position)

Description copied from interface: SDContextGenerator

Returns an array of contextual features for the potential sentence boundary at the specified position within the specified string buffer.

Specified by:

getContext in interface SDContextGenerator

Parameters:

sb - The string buffer for which sentences are being determined.

position - An index into the specified string buffer when a sentence boundary may occur.

Returns:

an array of contextual features for the potential sentence boundary at the specified position within the specified string buffer.

collectFeatures

protected void collectFeatures(java.lang.String prefix,
                               java.lang.String suffix,
                               java.lang.String previous,
                               java.lang.String next)

Determines some of the features for the sentence detector and adds them to list features.

Parameters:

prefix - String preceeding the eos character in the eos token.

suffix - String following the eos character in the eos token.

previous - Space delimited token preceeding token containing eos character.

next - Space delimited token following token containsing eos character.