aws java sdk 2

import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.s3.S3Client;
import software.amazon.awssdk.services.s3.model.GetObjectRequest;

import java.io.IOException;

public class S3ReadImg {
    public static void main(String[] args) throws IOException {

        S3Client s3 = S3Client.builder()
                .region(Region.EU_WEST_1) //
                .build(); // Might change for you

        GetObjectRequest getObjectRequest = GetObjectRequest.builder()
                .bucket("my_bucket_name")
                .key("four.bmp") // also tested for image types png, jpg, gif
                .build();

        byte[] objectResponse = s3.getObject(getObjectRequest).readAllBytes();

        String encodedfile = new String(java.util.Base64.getEncoder().encode(objectResponse), java.nio.charset.StandardCharsets.UTF_8);

    }
}