Connect to the Milvus Vector Database Using the Milvus Java SDK

This tutorial demonstrates how to connect and interact with the Milvus vector database using the Milvus Java SDK.

Prerequisites:

Java Development Kit (JDK) 11 or later
Apache Maven
A running instance of Milvus

Setting Up the Project

First, set up a new Maven project. In the “pom.xml” file of your project, include the Milvus Java SDK dependency:

<dependency>

<groupId>io.milvus</groupId>

<artifactId>milvus-sdk-java</artifactId>

<version>2.2.x</version>

</dependency>

NOTE: For compatibility, ensure that the version matches the version of your Milvus instance.

Connect to the Milvus Server

To interact with Milvus, create an instance of “MilvusServiceClient”:

import io.milvus.client.*;

final MilvusServiceClient milvusClient = new MilvusServiceClient(

ConnectParam.newBuilder()

.withHost("localhost")

.withPort(19530)

.build()

);

Make sure to replace the localhost and 19530 with your Milvus server’s host and port if it runs on a different hostname or port.

Create a Collection

Create a collection with a float vector field:

FieldType fieldType1 = FieldType.newBuilder()

.withName("book_id")

.withDataType(DataType.Int64)

.withPrimaryKey(true)

.withAutoID(false)

.build();

FieldType fieldType2 = FieldType.newBuilder()

.withName("word_count")

.withDataType(DataType.Int64)

.build();

FieldType fieldType3 = FieldType.newBuilder()

.withName("book_intro")

.withDataType(DataType.FloatVector)

.withDimension(2)

.build();

CreateCollectionParam createCollectionReq = CreateCollectionParam.newBuilder()

.withCollectionName("book")

.withDescription("Test book search")

.withShardsNum(2)

.addFieldType(fieldType1)

.addFieldType(fieldType2)

.addFieldType(fieldType3)

.withEnableDynamicField(true)

.build();

This creates a basic collection with the schema data to store the book information.

Insert the Data

You can then insert some sample vector data as follows:

Random ran = new Random();

List<Long> book_id_array = new ArrayList<>();

List<Long> word_count_array = new ArrayList<>();

List<List<Float>> book_intro_array = new ArrayList<>();

for (long i = 0L; i < 2000; ++i) {

book_id_array.add(i);

word_count_array.add(i + 10000);

List<Float> vector = new ArrayList<>();

for (int k = 0; k < 2; ++k) {

vector.add(ran.nextFloat());

}

book_intro_array.add(vector);

}

This uses the Java random features to add a random data.

Conclusion

With the Milvus Java SDK, you can interact with the Milvus vector database using Java. This tutorial covered the basics including connecting to a Milvus server, creating a collection, and inserting the data.