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

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.