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BertQuestionAnswerer

public class BertQuestionAnswerer

Returns the most possible answers on a given question for QA models (BERT, Albert, etc.).

The API expects a Bert based TFLite model with metadata containing the following information:

input_process_units for Wordpiece/Sentencepiece Tokenizer - Wordpiece Tokenizer can be used for a MobileBert model, Sentencepiece Tokenizer Tokenizer can be used for an Albert model.
3 input tensors with names "ids", "mask" and "segment_ids".
2 output tensors with names "end_logits" and "start_logits".

Nested Classes

class BertQuestionAnswerer.BertQuestionAnswererOptions Options for setting up a BertQuestionAnswerer.

Public Methods

List<QaAnswer>	answer(String context, String question) Answers question based on context, and returns a list of possible `QaAnswer`s.
static BertQuestionAnswerer	createAlbertQuestionAnswererFromFile(Context context, String modelPath, String sentencePieceModelPath) Creates a `BertQuestionAnswerer` instance with an Albert model and a sentence piece model file.
static BertQuestionAnswerer	createBertQuestionAnswererFromFile(Context context, String modelPath, String vocabPath) Creates a `BertQuestionAnswerer` instance with a Bert model and a vocabulary file.
static BertQuestionAnswerer	createFromFile(Context context, String modelPath) Creates a `BertQuestionAnswerer` instance from the default `BertQuestionAnswerer.BertQuestionAnswererOptions`.
static BertQuestionAnswerer	createFromFile(File modelFile) Creates a `BertQuestionAnswerer` instance from the default `BertQuestionAnswerer.BertQuestionAnswererOptions`.
static BertQuestionAnswerer	createFromFileAndOptions(File modelFile, BertQuestionAnswerer.BertQuestionAnswererOptions options) Creates a `BertQuestionAnswerer` instance from `BertQuestionAnswerer.BertQuestionAnswererOptions`.
static BertQuestionAnswerer	createFromFileAndOptions(Context context, String modelPath, BertQuestionAnswerer.BertQuestionAnswererOptions options) Creates a `BertQuestionAnswerer` instance from `BertQuestionAnswerer.BertQuestionAnswererOptions`.

Inherited Methods

From class org.tensorflow.lite.task.core.BaseTaskApi

synchronized void	close() Release the memory allocated from C++ and deregister the library from the static holder.
long	getNativeHandle()
boolean	isClosed()

From class java.lang.Object

boolean	equals(Object arg0)
final Class<?>	getClass()
int	hashCode()
final void	notify()
final void	notifyAll()
String	toString()
final void	wait(long arg0, int arg1)
final void	wait(long arg0)
final void	wait()

From interface java.io.Closeable

abstract void

close()

From interface org.tensorflow.lite.task.text.qa.QuestionAnswerer

abstract List<QaAnswer>

answer(String context, String question)

Answers question based on context, and returns a list of possible QaAnswers.

From interface java.lang.AutoCloseable

abstract void

close()

Public Methods

public List<QaAnswer> answer (String context, String question)

Answers question based on context, and returns a list of possible QaAnswers. Could be empty if no answer was found from the given context.

Parameters

context	context the question bases on
question	question to ask

Returns

a list of possible answers in QaAnswer

public static BertQuestionAnswerer createAlbertQuestionAnswererFromFile (Context context, String modelPath, String sentencePieceModelPath)

Creates a BertQuestionAnswerer instance with an Albert model and a sentence piece model file.

One suitable model is: https://tfhub.dev/tensorflow/lite-model/albert_lite_base/squadv1/1

Parameters

context	android context
modelPath	file path to the Albert model. Note: The model should not be compressed
sentencePieceModelPath	file path to the sentence piece model file. Note: The model should not be compressed

Returns

a BertQuestionAnswerer instance

Throws

IOException	If model file fails to load
IllegalArgumentException	if an argument is invalid
IllegalStateException	if there is an internal error
RuntimeException	if there is an otherwise unspecified error

public static BertQuestionAnswerer createBertQuestionAnswererFromFile (Context context, String modelPath, String vocabPath)

Creates a BertQuestionAnswerer instance with a Bert model and a vocabulary file.

One suitable model is: https://tfhub.dev/tensorflow/lite-model/mobilebert/1/default/1

Parameters

context	android context
modelPath	file path to the Bert model. Note: The model should not be compressed
vocabPath	file path to the vocabulary file. Note: The file should not be compressed

Returns

a BertQuestionAnswerer instance

Throws

IOException	If model file fails to load
IllegalArgumentException	if an argument is invalid
IllegalStateException	if there is an internal error
RuntimeException	if there is an otherwise unspecified error

public static BertQuestionAnswerer createFromFile (Context context, String modelPath)

Creates a BertQuestionAnswerer instance from the default BertQuestionAnswerer.BertQuestionAnswererOptions.

Parameters

context	android context
modelPath	file path to the model with metadata. Note: The model should not be compressed

Returns

a BertQuestionAnswerer instance

Throws

IOException	if model file fails to load
IllegalArgumentException	if an argument is invalid
IllegalStateException	if there is an internal error
RuntimeException	if there is an otherwise unspecified error

public static BertQuestionAnswerer createFromFile (File modelFile)

Creates a BertQuestionAnswerer instance from the default BertQuestionAnswerer.BertQuestionAnswererOptions.

Parameters

modelFile	a `File` object of the model

Returns

a BertQuestionAnswerer instance

Throws

IOException	if model file fails to load
IllegalArgumentException	if an argument is invalid
IllegalStateException	if there is an internal error
RuntimeException	if there is an otherwise unspecified error

public static BertQuestionAnswerer createFromFileAndOptions (File modelFile, BertQuestionAnswerer.BertQuestionAnswererOptions options)

Creates a BertQuestionAnswerer instance from BertQuestionAnswerer.BertQuestionAnswererOptions.

Parameters

modelFile	a `File` object of the model
options

Returns

a BertQuestionAnswerer instance

Throws

IOException	if model file fails to load
IllegalArgumentException	if an argument is invalid
IllegalStateException	if there is an internal error
RuntimeException	if there is an otherwise unspecified error

public static BertQuestionAnswerer createFromFileAndOptions (Context context, String modelPath, BertQuestionAnswerer.BertQuestionAnswererOptions options)

Creates a BertQuestionAnswerer instance from BertQuestionAnswerer.BertQuestionAnswererOptions.

Parameters

context	android context
modelPath	file path to the model with metadata. Note: The model should not be compressed
options

Returns

a BertQuestionAnswerer instance

Throws

IOException	if model file fails to load
IllegalArgumentException	if an argument is invalid
IllegalStateException	if there is an internal error
RuntimeException	if there is an otherwise unspecified error