Java

Use the Java SDK to store and retrieve data through a local daemon, a background service called antd. The client uses REST by default, with asynchronous and gRPC clients also available.

Install

The Java binding is not published to Maven Central for ant-sdk v0.12.1. Use JDK 17 or later and publish the exact release source to your local Maven repository.

git clone --branch v0.12.1 --depth 1 https://github.com/WithAutonomi/ant-sdk.git
test "$(git -C ant-sdk rev-parse HEAD)" = "f9cd5c5fc08133847909e47e04af186593ccbaee"
cd ant-sdk/antd-java
./gradlew publishToMavenLocal

Add mavenLocal() to your application's repositories and add the locally built artifact:

plugins {
    application
}

repositories {
    mavenLocal()
    mavenCentral()
}

dependencies {
    implementation("com.autonomi:antd-java:0.1.0")
}

java {
    toolchain {
        languageVersion.set(JavaLanguageVersion.of(17))
    }
}

application {
    mainClass.set("Connect")
}

The artifact version is 0.1.0 inside the ant-sdk v0.12.1 release source. The command above publishes only to your local Maven repository.

Connect to antd

Follow Start the Local Daemon to run antd before connecting.

import com.autonomi.antd.AntdClient;

public class Connect {
    public static void main(String[] args) throws Exception {
        try (var client = new AntdClient()) {
            var health = client.health();
            System.out.println("antd version: " + health.version());
        }
    }
}

Expected output:

antd version: <version>

The SDK also provides AsyncAntdClient and GrpcAntdClient.

Store and retrieve data

Start antd in a write-enabled mode before you upload. The public Autonomi Network requires wallet and Ethereum Virtual Machine (EVM) payment configuration. A local development network created with ant dev start includes that configuration.

import com.autonomi.antd.AntdClient;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;

public class Connect {
    public static void main(String[] args) throws Exception {
        try (var client = new AntdClient()) {
            byte[] payload = "Hello, Autonomi!".getBytes(StandardCharsets.UTF_8);
            var result = client.dataPutPublic(payload);
            System.out.println("Stored at: " + result.address());

            byte[] data = client.dataGetPublic(result.address());
            if (!Arrays.equals(data, payload)) {
                throw new IllegalStateException("downloaded data did not match the upload");
            }
            System.out.println("Retrieved: " + new String(data, StandardCharsets.UTF_8));
        }
    }
}

Expected output:

Stored at: <64-character hexadecimal address>
Retrieved: Hello, Autonomi!

Type mappings

Autonomi type	Java type
HealthStatus	com.autonomi.antd.models.HealthStatus
PutResult	com.autonomi.antd.models.PutResult
Raw data	byte[]

Error handling

antd 0.14.0 reports a valid address with no stored data as not found. Handle NotFoundException for this case. The client source is pinned independently to v0.12.1.

import com.autonomi.antd.AntdClient;
import com.autonomi.antd.errors.AntdException;
import com.autonomi.antd.errors.NotFoundException;

public class HandleErrors {
    public static void main(String[] args) throws Exception {
        String missingAddress = "0".repeat(64);

        try (var client = new AntdClient()) {
            client.dataGetPublic(missingAddress);
        } catch (NotFoundException exception) {
            System.out.println("No data is stored at that address");
        } catch (AntdException exception) {
            System.out.println(exception.getMessage());
        }
    }
}

Output when the valid address is not stored:

No data is stored at that address

Full API reference

For all available antd endpoints, see the REST API.