Java Client - Qdrant

Installation

Add to your pom.xml (Maven):

<dependency>
    <groupId>io.qdrant</groupId>
    <artifactId>client</artifactId>
    <version>1.11.0</version>
</dependency>

Or to your build.gradle (Gradle):

implementation 'io.qdrant:client:1.11.0'

Quick Start

import io.qdrant.client.QdrantClient;
import io.qdrant.client.QdrantGrpcClient;
import io.qdrant.client.grpc.Collections.*;
import io.qdrant.client.grpc.Points.*;
import static io.qdrant.client.PointIdFactory.id;
import static io.qdrant.client.ValueFactory.value;
import static io.qdrant.client.VectorsFactory.vectors;

import java.util.List;
import java.util.Map;
import java.util.concurrent.ExecutionException;

public class QdrantExample {
    public static void main(String[] args) 
            throws InterruptedException, ExecutionException {
        
        // Connect to Qdrant
        QdrantClient client = new QdrantClient(
            QdrantGrpcClient.newBuilder("localhost", 6334, false).build()
        );

        // Create collection
        client.createCollectionAsync(
            "my_collection",
            VectorParams.newBuilder()
                .setSize(384)
                .setDistance(Distance.Cosine)
                .build()
        ).get();

        // Upsert points
        client.upsertAsync(
            "my_collection",
            List.of(
                PointStruct.newBuilder()
                    .setId(id(1))
                    .setVectors(vectors(0.05f, 0.61f, 0.76f, 0.74f))
                    .putAllPayload(Map.of(
                        "city", value("Berlin"),
                        "country", value("Germany")
                    ))
                    .build(),
                PointStruct.newBuilder()
                    .setId(id(2))
                    .setVectors(vectors(0.19f, 0.81f, 0.75f, 0.11f))
                    .putAllPayload(Map.of(
                        "city", value("London"),
                        "country", value("UK")
                    ))
                    .build()
            )
        ).get();

        // Search
        List<ScoredPoint> searchResult = client.searchAsync(
            SearchPoints.newBuilder()
                .setCollectionName("my_collection")
                .addAllVector(List.of(0.2f, 0.1f, 0.9f, 0.7f))
                .setLimit(3)
                .setWithPayload(WithPayloadSelector.newBuilder()
                    .setEnable(true)
                    .build())
                .build()
        ).get();

        for (ScoredPoint point : searchResult) {
            System.out.println("ID: " + point.getId() + ", Score: " + point.getScore());
            System.out.println("Payload: " + point.getPayloadMap());
        }

        client.close();
    }
}

Repository

GitHub Repository

Official Java client: qdrant/java-client

Client Initialization

Basic Connection

import io.qdrant.client.QdrantClient;
import io.qdrant.client.QdrantGrpcClient;

// Connect to local instance
QdrantClient client = new QdrantClient(
    QdrantGrpcClient.newBuilder("localhost", 6334, false).build()
);

// Connect to Qdrant Cloud
QdrantClient cloudClient = new QdrantClient(
    QdrantGrpcClient.newBuilder(
        "your-cluster.cloud.qdrant.io",
        6334,
        true // Use TLS
    )
    .withApiKey("your-api-key")
    .build()
);

With Custom Options

import io.grpc.ManagedChannelBuilder;
import io.qdrant.client.QdrantClient;
import io.qdrant.client.QdrantGrpcClient;

import java.util.concurrent.TimeUnit;

QdrantGrpcClient grpcClient = QdrantGrpcClient.newBuilder(
    "localhost",
    6334,
    false
)
.withTimeout(30, TimeUnit.SECONDS)
.build();

QdrantClient client = new QdrantClient(grpcClient);

Collection Management

Create Collection

import io.qdrant.client.grpc.Collections.*;

client.createCollectionAsync(
    CreateCollection.newBuilder()
        .setCollectionName("my_collection")
        .setVectorsConfig(VectorsConfig.newBuilder()
            .setParams(VectorParams.newBuilder()
                .setSize(768)
                .setDistance(Distance.Cosine)
                .setOnDisk(false)
                .setHnswConfig(HnswConfigDiff.newBuilder()
                    .setM(16)
                    .setEfConstruct(100)
                    .setFullScanThreshold(10000)
                    .build())
                .build())
            .build())
        .setReplicationFactor(2)
        .setWriteConsistencyFactor(1)
        .build()
).get();

Create with Multiple Vectors

import java.util.Map;

client.createCollectionAsync(
    CreateCollection.newBuilder()
        .setCollectionName("multi_vector")
        .setVectorsConfig(VectorsConfig.newBuilder()
            .setParamsMap(VectorParamsMap.newBuilder()
                .putAllMap(Map.of(
                    "text", VectorParams.newBuilder()
                        .setSize(768)
                        .setDistance(Distance.Cosine)
                        .build(),
                    "image", VectorParams.newBuilder()
                        .setSize(512)
                        .setDistance(Distance.Euclid)
                        .build()
                ))
                .build())
            .build())
        .build()
).get();

Get Collection Info

CollectionInfo info = client.getCollectionInfoAsync("my_collection").get();

System.out.println("Status: " + info.getStatus());
System.out.println("Vectors count: " + info.getVectorsCount());
System.out.println("Points count: " + info.getPointsCount());

List Collections

import io.qdrant.client.grpc.Collections.CollectionDescription;

List<CollectionDescription> collections = client.listCollectionsAsync().get();

for (CollectionDescription collection : collections) {
    System.out.println(collection.getName());
}

Delete Collection

client.deleteCollectionAsync("my_collection").get();

Point Operations

Upsert Points

import io.qdrant.client.grpc.Points.*;
import static io.qdrant.client.PointIdFactory.id;
import static io.qdrant.client.ValueFactory.value;
import static io.qdrant.client.VectorsFactory.vectors;

import java.util.List;
import java.util.Map;

client.upsertAsync(
    "my_collection",
    List.of(
        PointStruct.newBuilder()
            .setId(id(1))
            .setVectors(vectors(0.05f, 0.61f, 0.76f, 0.74f))
            .putAllPayload(Map.of(
                "title", value("Document 1"),
                "category", value("technology"),
                "views", value(1500),
                "tags", value(List.of("ai", "ml", "vector-db"))
            ))
            .build(),
        PointStruct.newBuilder()
            .setId(id(2))
            .setVectors(vectors(0.19f, 0.81f, 0.75f, 0.11f))
            .putAllPayload(Map.of(
                "title", value("Document 2")
            ))
            .build()
    ),
    true // wait
).get();

Upsert with UUID

import java.util.UUID;
import static io.qdrant.client.PointIdFactory.id;

UUID uuid = UUID.randomUUID();

client.upsertAsync(
    "my_collection",
    List.of(
        PointStruct.newBuilder()
            .setId(id(uuid))
            .setVectors(vectors(0.1f, 0.2f, 0.3f))
            .putAllPayload(Map.of("key", value("value")))
            .build()
    )
).get();

Batch Upsert

import java.util.ArrayList;
import java.util.List;
import java.util.Random;

int batchSize = 100;
int totalPoints = 10000;
Random random = new Random();

for (int i = 0; i < totalPoints; i += batchSize) {
    List<PointStruct> points = new ArrayList<>();
    
    for (int j = i; j < i + batchSize && j < totalPoints; j++) {
        float[] vector = new float[384];
        for (int k = 0; k < 384; k++) {
            vector[k] = random.nextFloat();
        }
        
        points.add(
            PointStruct.newBuilder()
                .setId(id(j))
                .setVectors(vectors(vector))
                .putAllPayload(Map.of("index", value(j)))
                .build()
        );
    }
    
    client.upsertAsync("my_collection", points, false).get();
}

Get Points

import static io.qdrant.client.PointIdFactory.id;
import static io.qdrant.client.WithPayloadSelectorFactory.enable;
import static io.qdrant.client.WithVectorsSelectorFactory.enable;

List<RetrievedPoint> points = client.retrieveAsync(
    "my_collection",
    List.of(id(1), id(2), id(3)),
    enable(true), // with_payload
    enable(true), // with_vectors
    null
).get();

for (RetrievedPoint point : points) {
    System.out.println("ID: " + point.getId());
    System.out.println("Vectors: " + point.getVectors());
    System.out.println("Payload: " + point.getPayloadMap());
}

Delete Points

import io.qdrant.client.grpc.Points.*;
import static io.qdrant.client.PointIdFactory.id;
import static io.qdrant.client.ConditionFactory.matchKeyword;

// Delete by IDs
client.deleteAsync(
    "my_collection",
    List.of(id(1), id(2), id(3)),
    true, // wait
    null,
    null
).get();

// Delete by filter
client.deleteAsync(
    "my_collection",
    Filter.newBuilder()
        .addMust(matchKeyword("category", "outdated"))
        .build(),
    true,
    null
).get();

Search Operations

Basic Search

import io.qdrant.client.grpc.Points.*;
import static io.qdrant.client.WithPayloadSelectorFactory.enable;

import java.util.List;

List<ScoredPoint> results = client.searchAsync(
    SearchPoints.newBuilder()
        .setCollectionName("my_collection")
        .addAllVector(List.of(0.2f, 0.1f, 0.9f, 0.7f))
        .setLimit(10)
        .setWithPayload(enable(true))
        .build()
).get();

for (ScoredPoint result : results) {
    System.out.println("ID: " + result.getId() + ", Score: " + result.getScore());
    System.out.println("Payload: " + result.getPayloadMap());
}

Search with Filtering

import static io.qdrant.client.ConditionFactory.*;

List<ScoredPoint> results = client.searchAsync(
    SearchPoints.newBuilder()
        .setCollectionName("my_collection")
        .addAllVector(List.of(0.2f, 0.1f, 0.9f, 0.7f))
        .setFilter(Filter.newBuilder()
            .addMust(matchKeyword("category", "technology"))
            .addMust(range("views", 
                Range.newBuilder()
                    .setGte(1000.0)
                    .setLt(10000.0)
                    .build()))
            .build())
        .setLimit(5)
        .setScoreThreshold(0.7f)
        .build()
).get();

Search with Parameters

List<ScoredPoint> results = client.searchAsync(
    SearchPoints.newBuilder()
        .setCollectionName("my_collection")
        .addAllVector(List.of(0.2f, 0.1f, 0.9f, 0.7f))
        .setLimit(20)
        .setParams(SearchParams.newBuilder()
            .setHnswEf(128)
            .setExact(false)
            .setQuantization(QuantizationSearchParams.newBuilder()
                .setIgnore(false)
                .setRescore(true)
                .setOversampling(2.0)
                .build())
            .build())
        .build()
).get();

Batch Search

import io.qdrant.client.grpc.Points.*;

List<List<ScoredPoint>> batchResults = client.searchBatchAsync(
    "my_collection",
    List.of(
        SearchPoints.newBuilder()
            .addAllVector(List.of(0.2f, 0.1f, 0.9f))
            .setLimit(5)
            .build(),
        SearchPoints.newBuilder()
            .addAllVector(List.of(0.5f, 0.3f, 0.2f))
            .setLimit(10)
            .build()
    ),
    null
).get();

for (int i = 0; i < batchResults.size(); i++) {
    System.out.println("Results for query " + i + ":");
    for (ScoredPoint point : batchResults.get(i)) {
        System.out.println("  ID: " + point.getId() + ", Score: " + point.getScore());
    }
}

Recommendations

import static io.qdrant.client.PointIdFactory.id;

List<ScoredPoint> results = client.recommendAsync(
    RecommendPoints.newBuilder()
        .setCollectionName("my_collection")
        .addAllPositive(List.of(id(1), id(2), id(3)))
        .addAllNegative(List.of(id(10)))
        .setLimit(10)
        .setWithPayload(enable(true))
        .build()
).get();

for (ScoredPoint result : results) {
    System.out.println("ID: " + result.getId() + ", Score: " + result.getScore());
}

Query API (Universal)

import io.qdrant.client.grpc.Points.*;
import static io.qdrant.client.QueryFactory.nearest;

List<ScoredPoint> results = client.queryAsync(
    QueryPoints.newBuilder()
        .setCollectionName("my_collection")
        .setQuery(nearest(0.1f, 0.2f, 0.3f, 0.4f))
        .setLimit(10)
        .setWithPayload(enable(true))
        .build()
).get();

Payload Operations

Set Payload

import static io.qdrant.client.PointIdFactory.id;
import static io.qdrant.client.ValueFactory.value;

client.setPayloadAsync(
    "my_collection",
    Map.of(
        "new_field", value("value"),
        "updated_at", value("2024-01-01")
    ),
    List.of(id(1), id(2), id(3)),
    null,
    null,
    null
).get();

Overwrite Payload

client.overwritePayloadAsync(
    "my_collection",
    Map.of("only_field", value("value")),
    List.of(id(1), id(2)),
    null,
    null,
    null
).get();

Delete Payload Keys

client.deletePayloadAsync(
    "my_collection",
    List.of("old_field", "deprecated"),
    List.of(id(1), id(2), id(3)),
    null,
    null,
    null
).get();

Clear Payload

client.clearPayloadAsync(
    "my_collection",
    List.of(id(1), id(2), id(3)),
    null,
    null,
    null
).get();

Scroll (Pagination)

import io.qdrant.client.grpc.Points.*;

PointId offset = null;
List<RetrievedPoint> allPoints = new ArrayList<>();

while (true) {
    List<RetrievedPoint> points = client.scrollAsync(
        ScrollPoints.newBuilder()
            .setCollectionName("my_collection")
            .setLimit(100)
            .setOffset(offset != null ? offset : PointId.getDefaultInstance())
            .setWithPayload(enable(true))
            .build()
    ).get();

    allPoints.addAll(points);
    
    if (points.isEmpty() || points.size() < 100) {
        break;
    }
    
    offset = points.get(points.size() - 1).getId();
}

System.out.println("Total points: " + allPoints.size());

Payload Indexing

import io.qdrant.client.grpc.Points.*;

// Create keyword index
client.createPayloadIndexAsync(
    "my_collection",
    "category",
    PayloadSchemaType.Keyword,
    null,
    null,
    null
).get();

// Create text index
client.createPayloadIndexAsync(
    "my_collection",
    "description",
    PayloadSchemaType.Text,
    PayloadIndexParams.newBuilder()
        .setTextIndexParams(TextIndexParams.newBuilder()
            .setTokenizer(TokenizerType.Word)
            .setLowercase(true)
            .setMinTokenLen(2)
            .setMaxTokenLen(20)
            .build())
        .build(),
    null,
    null
).get();

// Delete index
client.deletePayloadIndexAsync(
    "my_collection",
    "category",
    null,
    null
).get();

Count Points

import io.qdrant.client.grpc.Points.*;

long count = client.countAsync(
    CountPoints.newBuilder()
        .setCollectionName("my_collection")
        .setExact(true)
        .build()
).get();

System.out.println("Total points: " + count);

Error Handling

import io.grpc.StatusRuntimeException;
import io.grpc.Status;

try {
    CollectionInfo info = client.getCollectionInfoAsync("nonexistent").get();
} catch (ExecutionException e) {
    if (e.getCause() instanceof StatusRuntimeException) {
        StatusRuntimeException grpcException = (StatusRuntimeException) e.getCause();
        
        if (grpcException.getStatus().getCode() == Status.Code.NOT_FOUND) {
            System.out.println("Collection not found");
        } else {
            System.err.println("gRPC error: " + grpcException.getStatus());
        }
    } else {
        System.err.println("Unexpected error: " + e.getMessage());
    }
}

CompletableFuture Support

import java.util.concurrent.CompletableFuture;
import java.util.List;

// All async methods return CompletableFuture
CompletableFuture<List<ScoredPoint>> searchFuture = client.searchAsync(
    SearchPoints.newBuilder()
        .setCollectionName("my_collection")
        .addAllVector(List.of(0.2f, 0.1f, 0.9f))
        .setLimit(10)
        .build()
);

// Chain operations
searchFuture
    .thenApply(results -> {
        System.out.println("Found " + results.size() + " results");
        return results;
    })
    .thenAccept(results -> {
        results.forEach(point -> 
            System.out.println("ID: " + point.getId())
        );
    })
    .exceptionally(ex -> {
        System.err.println("Search failed: " + ex.getMessage());
        return null;
    });

Reactive Programming

import io.reactivex.rxjava3.core.Observable;
import java.util.concurrent.CompletableFuture;

// Convert CompletableFuture to Observable
Observable<List<ScoredPoint>> searchObservable = 
    Observable.fromCompletionStage(
        client.searchAsync(
            SearchPoints.newBuilder()
                .setCollectionName("my_collection")
                .addAllVector(List.of(0.2f, 0.1f, 0.9f))
                .setLimit(10)
                .build()
        )
    );

searchObservable
    .flatMapIterable(results -> results)
    .filter(point -> point.getScore() > 0.7)
    .subscribe(
        point -> System.out.println("ID: " + point.getId()),
        error -> System.err.println("Error: " + error),
        () -> System.out.println("Completed")
    );

Spring Boot Integration

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import io.qdrant.client.QdrantClient;
import io.qdrant.client.QdrantGrpcClient;

@Configuration
public class QdrantConfig {
    
    @Bean
    public QdrantClient qdrantClient() {
        return new QdrantClient(
            QdrantGrpcClient.newBuilder("localhost", 6334, false).build()
        );
    }
}

// Service class
import org.springframework.stereotype.Service;

@Service
public class SearchService {
    
    private final QdrantClient client;
    
    public SearchService(QdrantClient client) {
        this.client = client;
    }
    
    public List<ScoredPoint> search(float[] vector) 
            throws InterruptedException, ExecutionException {
        return client.searchAsync(
            SearchPoints.newBuilder()
                .setCollectionName("my_collection")
                .addAllVector(Arrays.stream(vector)
                    .boxed()
                    .collect(Collectors.toList()))
                .setLimit(10)
                .build()
        ).get();
    }
}

Best Practices

Performance tips:

Reuse QdrantClient instances (singleton pattern)
Use CompletableFuture for async operations
Leverage batch operations for bulk inserts
Configure appropriate timeouts for long operations
Always close the client when done

Common issues:

Always handle ExecutionException for async operations
Use appropriate gRPC error handling
Ensure vector dimensions match collection config
Don’t forget to call .get() on async methods

Next Steps

Python Client

Python client documentation

gRPC API

Learn about gRPC protocol

Overview

REST API

gRPC API

Client Libraries

​Installation

​Quick Start

​Repository

GitHub Repository

​Client Initialization

​Basic Connection

​With Custom Options

​Collection Management

​Create Collection

​Create with Multiple Vectors

​Get Collection Info

​List Collections

​Delete Collection

​Point Operations

​Upsert Points

​Upsert with UUID

​Batch Upsert

​Get Points

​Delete Points

​Search Operations

​Basic Search

​Search with Filtering

​Search with Parameters

​Batch Search

​Recommendations

​Query API (Universal)

​Payload Operations

​Set Payload

​Overwrite Payload

​Delete Payload Keys

​Clear Payload

​Scroll (Pagination)

​Payload Indexing

​Count Points

​Error Handling

​CompletableFuture Support

​Reactive Programming

​Spring Boot Integration

​Best Practices

​Next Steps

Python Client

gRPC API

Installation

Quick Start

Repository

Client Initialization

Basic Connection

With Custom Options

Collection Management

Create Collection

Create with Multiple Vectors

Get Collection Info

List Collections

Delete Collection

Point Operations

Upsert Points

Upsert with UUID

Batch Upsert

Get Points

Delete Points

Search Operations

Basic Search

Search with Filtering

Search with Parameters

Batch Search

Recommendations

Query API (Universal)

Payload Operations

Set Payload

Overwrite Payload

Delete Payload Keys

Clear Payload

Scroll (Pagination)

Payload Indexing

Count Points

Error Handling

CompletableFuture Support

Reactive Programming

Spring Boot Integration

Best Practices

Next Steps