Package opennlp.tools.util.featuregen

Class BrownCluster

java.lang.Object

opennlp.tools.util.featuregen.BrownCluster

All Implemented Interfaces:

SerializableArtifact

public class BrownCluster
extends Object
implements SerializableArtifact

Class to load a Brown cluster document: word\tword_class\tprob

Originally available at: http://metaoptimize.com/projects/wordreprs/.

Further details can be found in the related research paper.

The file containing the clustering lexicon has to be passed as the value of the dict attribute of each BrownCluster feature generator.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	BrownCluster.BrownClusterSerializer

Constructor Summary

Constructors

Constructor	Description
BrownCluster(InputStream in)	Instatiates a BrownCluster and its related token to cluster map via an InputStream.

Method Summary

Modifier and Type	Method	Description
Class<?>	getArtifactSerializerClass()	Retrieves the class which can serialize and recreate this artifact.
String	lookupToken(String string)	Check if a token is in the Brown:paths, token map.
void	serialize(OutputStream out)

Methods inherited from class java.lang.Object

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

Constructor Details

BrownCluster

public BrownCluster(InputStream in)
             throws IOException

Instatiates a BrownCluster and its related token to cluster map via an InputStream.

Note: Only tokens with frequency bigger than 5 will be added.

Parameters:

in - A valid, open InputStream to read from.

Throws:

IOException - Thrown if errors occurred reading from in.

Method Details

lookupToken

public String lookupToken(String string)

Check if a token is in the Brown:paths, token map.

Parameters:

string - the token to look-up

Returns:

the brown class if such token is in the brown cluster map

serialize

public void serialize(OutputStream out)
               throws IOException

Throws:

IOException

getArtifactSerializerClass

public Class<?> getArtifactSerializerClass()

Description copied from interface: SerializableArtifact

Retrieves the class which can serialize and recreate this artifact.

Note: The serializer class must have a public zero argument constructor or an exception is thrown during model serialization/loading.

Specified by:

getArtifactSerializerClass in interface SerializableArtifact

Returns:

The corresponding ArtifactSerializer class.