Package opennlp.tools.parser

Class ChunkContextGenerator

java.lang.Object

opennlp.tools.parser.ChunkContextGenerator

All Implemented Interfaces:

ChunkerContextGenerator, BeamSearchContextGenerator<TokenTag>

public class ChunkContextGenerator
extends Object
implements ChunkerContextGenerator

Creates predictive context for the pre-chunking phases of parsing.

Constructor Summary

Constructors

Constructor	Description
ChunkContextGenerator()	Initializes a ChunkContextGenerator instance.
ChunkContextGenerator(int cacheSize)	Initializes a ChunkContextGenerator instance with a custom cacheSize.

Method Summary

Modifier and Type	Method	Description
String[]	getContext(int i, String[] words, String[] prevDecisions, Object[] ac)	Deprecated. Use getContext(int, String[], String[], String[]) instead.
String[]	getContext(int i, String[] words, String[] tags, String[] preds)	Retrieves the contexts for chunking of the specified idx.
String[]	getContext(int index, TokenTag[] sequence, String[] priorDecisions, Object[] additionalContext)	Returns the context for the specified position in the specified sequence (list).
String[]	getContext(Object o)	Deprecated. Use getContext(int, String[], String[], String[]) instead.

Methods inherited from class java.lang.Object

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

Constructor Detail

ChunkContextGenerator

public ChunkContextGenerator()

Initializes a ChunkContextGenerator instance.

ChunkContextGenerator

public ChunkContextGenerator(int cacheSize)

Initializes a ChunkContextGenerator instance with a custom cacheSize.

Parameters:

cacheSize - The cache size. Must be greater than 0 to have an effect.

Method Detail

getContext

@Deprecated
public String[] getContext(Object o)

Deprecated.

Use getContext(int, String[], String[], String[]) instead.

getContext

@Deprecated
public String[] getContext(int i,
                           String[] words,
                           String[] prevDecisions,
                           Object[] ac)

Deprecated.

Use getContext(int, String[], String[], String[]) instead.

getContext

public String[] getContext(int i,
                           String[] words,
                           String[] tags,
                           String[] preds)

Description copied from interface: ChunkerContextGenerator

Retrieves the contexts for chunking of the specified idx.

Specified by:

getContext in interface ChunkerContextGenerator

Parameters:

i - The index of the token in the specified toks array for which the context should be constructed.

words - The tokens of the sentence. The toString methods of these objects should return the token text.

tags - The POS tags for the specified tokens.

preds - The previous decisions made in the tagging of this sequence. Only indices less than idx will be examined.

Returns:

An array of predictive contexts on which a model basis its decisions.

getContext

public String[] getContext(int index,
                           TokenTag[] sequence,
                           String[] priorDecisions,
                           Object[] additionalContext)

Description copied from interface: BeamSearchContextGenerator

Returns the context for the specified position in the specified sequence (list).

Specified by:

getContext in interface BeamSearchContextGenerator<TokenTag>

Parameters:

index - The index of the sequence.

sequence - The sequence of items over which the beam search is performed.

priorDecisions - The sequence of decisions made prior to the context for which this decision is being made.

additionalContext - Any addition context specific to a class implementing this interface.

Returns:

The context for the specified index in the specified sequence.