Interface QueryRouter

All Known Implementing Classes:

DefaultQueryRouter, LanguageModelQueryRouter

public interface QueryRouter

Routes the given Query to one or multiple ContentRetrievers.
The goal is to ensure that Content is retrieved only from relevant data sources.
Some potential approaches include:

- Using an LLM (see LanguageModelQueryRouter)
- Using an EmbeddingModel (aka "semantic routing", see EmbeddingModelTextClassifier in the langchain4j module)
- Using keyword-based routing
- Route depending on the user (query.metadata().chatMemoryId()) and/or permissions

See Also:

• DefaultQueryRouter
• LanguageModelQueryRouter

Method Summary

Modifier and Type	Method	Description
Collection<ContentRetriever>	route(Query query)	Routes the given Query to one or multiple ContentRetrievers.
default CompletableFuture<Collection<ContentRetriever>>	routeAsync(Query query)	Non-blocking counterpart of route(Query), invoked by the asynchronous (CompletableFuture/CompletionStage) and reactive (Flow.Publisher) AI Service modes when RAG is configured.

Method Details

route

Collection<ContentRetriever> route(Query query)

Routes the given Query to one or multiple ContentRetrievers.

Parameters:

query - The Query to be routed.

Returns:

A collection of one or more ContentRetrievers to which the Query should be routed.

routeAsync

@Experimental
default CompletableFuture<Collection<ContentRetriever>> routeAsync(Query query)

Non-blocking counterpart of route(Query), invoked by the asynchronous (CompletableFuture/CompletionStage) and reactive (Flow.Publisher) AI Service modes when RAG is configured.

The default implementation returns a failed future carrying AsyncNotSupportedException: a router backed by a blocking LLM call (e.g. LanguageModelQueryRouter) must opt in by overriding this method to stay off the calling thread. A router that cannot be made non-blocking is still usable from these modes via DefaultRetrievalAugmentor, which offloads the blocking route(Query) to its executor.

Parameters:

query - The Query to be routed.

Returns:

A CompletableFuture of one or more ContentRetrievers to route the Query to.

Since:

1.20.0