Package dev.langchain4j.model.openai

Class OpenAiTokenCountEstimator

java.lang.Object

dev.langchain4j.model.openai.OpenAiTokenCountEstimator

All Implemented Interfaces:

TokenCountEstimator

public class OpenAiTokenCountEstimator
extends Object
implements TokenCountEstimator

This class can be used to estimate the cost (in tokens) before calling OpenAI. Magic numbers present in this class were found empirically while testing. There are integration tests in place that are making sure that the calculations here are very close to that of OpenAI.

Constructor Summary

Constructors

Constructor	Description
OpenAiTokenCountEstimator(OpenAiChatModelName modelName)	Creates an instance of the OpenAiTokenCountEstimator for a given OpenAiChatModelName.
OpenAiTokenCountEstimator(OpenAiEmbeddingModelName modelName)	Creates an instance of the OpenAiTokenCountEstimator for a given OpenAiEmbeddingModelName.
OpenAiTokenCountEstimator(OpenAiLanguageModelName modelName)	Creates an instance of the OpenAiTokenCountEstimator for a given OpenAiLanguageModelName.
OpenAiTokenCountEstimator(String modelName)	Creates an instance of the OpenAiTokenCountEstimator for a given model name.

Method Summary

Modifier and Type	Method	Description
String	decode(List<Integer> tokens)
List<Integer>	encode(String text)
List<Integer>	encode(String text, int maxTokensToEncode)
int	estimateTokenCountInMessage(ChatMessage message)	Estimates the count of tokens in the given message.
int	estimateTokenCountInMessages(Iterable<ChatMessage> messages)	Estimates the count of tokens in the given messages.
int	estimateTokenCountInText(String text)	Estimates the count of tokens in the given text.

Methods inherited from class java.lang.Object

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

Constructor Details

OpenAiTokenCountEstimator

public OpenAiTokenCountEstimator(OpenAiChatModelName modelName)

Creates an instance of the OpenAiTokenCountEstimator for a given OpenAiChatModelName.

OpenAiTokenCountEstimator

public OpenAiTokenCountEstimator(OpenAiEmbeddingModelName modelName)

Creates an instance of the OpenAiTokenCountEstimator for a given OpenAiEmbeddingModelName.

OpenAiTokenCountEstimator

public OpenAiTokenCountEstimator(OpenAiLanguageModelName modelName)

Creates an instance of the OpenAiTokenCountEstimator for a given OpenAiLanguageModelName.

OpenAiTokenCountEstimator

public OpenAiTokenCountEstimator(String modelName)

Creates an instance of the OpenAiTokenCountEstimator for a given model name.

Method Details

estimateTokenCountInText

public int estimateTokenCountInText(String text)

Description copied from interface: TokenCountEstimator

Estimates the count of tokens in the given text.

Specified by:

estimateTokenCountInText in interface TokenCountEstimator

Parameters:

text - the text.

Returns:

the estimated count of tokens.

estimateTokenCountInMessage

public int estimateTokenCountInMessage(ChatMessage message)

Description copied from interface: TokenCountEstimator

Estimates the count of tokens in the given message.

Specified by:

estimateTokenCountInMessage in interface TokenCountEstimator

Parameters:

message - the message.

Returns:

the estimated count of tokens.

estimateTokenCountInMessages

public int estimateTokenCountInMessages(Iterable<ChatMessage> messages)

Description copied from interface: TokenCountEstimator

Estimates the count of tokens in the given messages.

Specified by:

estimateTokenCountInMessages in interface TokenCountEstimator

Parameters:

messages - the messages.

Returns:

the estimated count of tokens.

encode

public List<Integer> encode(String text)

encode

public List<Integer> encode(String text,
 int maxTokensToEncode)

decode

public String decode(List<Integer> tokens)