Package opennlp.tools.namefind

Class BioCodec

java.lang.Object

opennlp.tools.namefind.BioCodec

All Implemented Interfaces:

SequenceCodec<String>

public class BioCodec
extends Object
implements SequenceCodec<String>

The default SequenceCodec implementation according to the BIO scheme:

• B: 'beginning' of a NE
• I: 'inside', the word is inside a NE
• O: 'outside', the word is a regular word outside a NE

See also the paper by Roth D. and Ratinov L.: Design Challenges and Misconceptions in Named Entity Recognition.

See Also:

• SequenceCodec
• BilouCodec

Field Summary

Fields

Modifier and Type	Field	Description
static final String	CONTINUE
static final String	OTHER
static final String	START

Fields inherited from interface opennlp.tools.util.SequenceCodec

DEFAULT_PREFIX

Constructor Summary

Constructors

Constructor	Description
BioCodec()

Method Summary

Modifier and Type	Method	Description
boolean	areOutcomesCompatible(String[] outcomes)	Checks if the outcomes of a model are compatible with this SequenceCodec.
NameFinderSequenceValidator	createSequenceValidator()
Span[]	decode(List<String> c)	Decodes a sequence of objects into Span objects.
String[]	encode(Span[] names, int length)	Encodes Span objects into a sequence of objects.

Methods inherited from class java.lang.Object

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

Field Details

START

public static final String START

See Also:

• Constant Field Values

CONTINUE

public static final String CONTINUE

See Also:

• Constant Field Values

OTHER

public static final String OTHER

See Also:

• Constant Field Values

Constructor Details

BioCodec

public BioCodec()

Method Details

decode

public Span[] decode(List<String> c)

Description copied from interface: SequenceCodec

Decodes a sequence of objects into Span objects.

Specified by:

decode in interface SequenceCodec<String>

Parameters:

c - A list of SequenceCodec to decode.

Returns:

A Span array encapsulating the decoded elements in c.

encode

public String[] encode(Span[] names,
 int length)

Description copied from interface: SequenceCodec

Encodes Span objects into a sequence of objects.

Specified by:

encode in interface SequenceCodec<String>

Parameters:

names - A list of elements to encode.

length - The length to respect.

Returns:

An array of SequenceCodec to encode.

createSequenceValidator

public NameFinderSequenceValidator createSequenceValidator()

Specified by:

createSequenceValidator in interface SequenceCodec<String>

Returns:

A SequenceValidator which can validate a sequence of outcomes.

areOutcomesCompatible

public boolean areOutcomesCompatible(String[] outcomes)

Description copied from interface: SequenceCodec

Checks if the outcomes of a model are compatible with this SequenceCodec.

Specified by:

areOutcomesCompatible in interface SequenceCodec<String>

Parameters:

outcomes - The possible model outcomes.

Returns:

true if outcomes are type compatible, false otherwise.