Java Quickstart Guide

Connect a Java application to SILO with the MinIO Java SDK.

MinIO Java SDK

SILO implements the S3-compatible server contract, so Java applications can use the upstream MinIO Java SDK directly. The SDK supports Java 8 and later; select a runtime that is also supported by your application framework.

This page was verified with SDK 9.0.3. Check the current releases and Maven Central metadata before pinning a version.

Install the package

Add the dependency to Maven:

XML

<dependency>
  <groupId>io.minio</groupId>
  <artifactId>minio</artifactId>
  <version>9.0.3</version>
</dependency>

Or to Gradle:

KOTLIN

implementation("io.minio:minio:9.0.3")

Configure the connection

BASH

export S3_ENDPOINT=http://127.0.0.1:9000
export S3_ACCESS_KEY=silo-admin
export S3_SECRET_KEY=replace-with-a-strong-secret

Unlike some other MinIO SDKs, the Java builder accepts a complete endpoint URL, including the http:// or https:// scheme. Keep credentials outside source control.

Create a bucket and upload an object

JAVA

import io.minio.BucketExistsArgs;
import io.minio.MakeBucketArgs;
import io.minio.MinioClient;
import io.minio.PutObjectArgs;
import java.io.ByteArrayInputStream;
import java.nio.charset.StandardCharsets;

public final class Quickstart {
  private static String required(String name) {
    String value = System.getenv(name);
    if (value == null || value.isBlank()) {
      throw new IllegalStateException(name + " is required");
    }
    return value;
  }

  public static void main(String[] args) throws Exception {
    MinioClient client =
        MinioClient.builder()
            .endpoint(required("S3_ENDPOINT"))
            .credentials(required("S3_ACCESS_KEY"), required("S3_SECRET_KEY"))
            .build();

    String bucket = "java-quickstart";
    String object = "hello.txt";
    byte[] payload = "hello from SILO\n".getBytes(StandardCharsets.UTF_8);

    boolean exists =
        client.bucketExists(BucketExistsArgs.builder().bucket(bucket).build());
    if (!exists) {
      client.makeBucket(MakeBucketArgs.builder().bucket(bucket).build());
    }

    try (ByteArrayInputStream stream = new ByteArrayInputStream(payload)) {
      client.putObject(
          PutObjectArgs.builder()
              .bucket(bucket)
              .object(object)
              .stream(stream, payload.length, -1)
              .contentType("text/plain")
              .build());
    }

    System.out.printf("Uploaded %s: %d bytes%n", object, payload.length);
  }
}

Use the SDK’s Javadoc and maintained examples for presigned URLs, encryption, notifications, object locking, multipart operations, and other APIs.

Production checklist

Use TLS and verify the server certificate and trust store.
Load credentials from a secret manager or protected environment.
Grant the application only the bucket and object permissions it needs.
Pin and test the JDK, SDK, HTTP client, and framework versions together.
Configure timeouts and handle SDK exceptions, retries, streams, and incomplete multipart uploads explicitly.

See Identity and Access Management for server-side policy configuration.