EVER-SDK for Java

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This is a Java binding project for EVER-SDK library that is compatible with Everscale, Venom, GOSH & TON blockchain networks. Binding calls JSON-RPC interface of EVER-SDK. Native calls are based on modern Foreign Function & Memory API.

This artifact provides full binding functionality, but doesn't include higher level helpers for development, tests or fast prototyping. Try our larger Java4Ever framework that is based on this binding for easier work with TVM blockchains.

Goals

• Provide Java binding for EVER-SDK based on modern Java native memory access
• Support any modern versions of EVER-SDK without rebuild of binding itself
• Support custom EVER-SDK binaries

Quick start

Prerequisites

• Install JDK 22 (link)

Add java4ever to your Maven of Gradle setup:

• Gradle

dependencies {
    implementation 'tech.deplant.java4ever:java4ever-binding:3.0.0'
}

• Maven

<dependency>
    <groupId>tech.deplant.java4ever</groupId>
    <artifactId>java4ever-binding</artifactId>
    <version>3.0.0</version>
</dependency>

Examples and Guides

Setting up SDK

SDK setup consists of two steps:

1. Loading EVER-SDK library (should be done once)
2. Creating context/session with certain config (should be done for every new endpoint or config change)

Both steps are described below.

Loading EVER-SDK library

To load EVER-SDK connection to JVM, use EverSdk.load() static method. Loaded EVER-SDK is a singleton, you can't use other version of library simultaneously. Java4Ever stores wrapped copy of actual EVER-SDK libraries in its resources. To load wrapped library, run:

EverSdk.load();

Note: We found problems with loading library from resources using Spring's fatJar bundles. Please, use alternative loaders if you use fatJar too.

If you want to use custom binaries or version, you should use other loaders. All loaders are just ways to reach library, so you should get/build ton_client library first. You can find EverX precompiled EVER-SDK files here. Here are the examples of loader options:

// loads library from path saved in environment variable
EverSdk.load(AbsolutePathLoader.ofSystemEnv("TON_CLIENT_LIB")); 
// loads library from ~ (user home)
EverSdk.load(AbsolutePathLoader.ofUserDir("libton_client.so")); 
// loads from any absolute path
EverSdk.load(new AbsolutePathLoader(Path.of("/home/ton/lib/libton_client.so"))); 
// loads library from java.library.path JVM argument
EverSdk.load(new JavaLibraryPathLoader("ton_client")); 

Creating config context and specifying endpoints

Context configuration is needed to provide EVER-SDK library with your endpoints, timeouts and other settings. You can find a list of endpoints here: https://docs.evercloud.dev/products/evercloud/networks-endpoints If you're working with Everscale mainnet, here you can register your app and receive "ProjectID" part of the URL: https://dashboard.evercloud.dev/

// creates default EVER-SDK context without specifying endpoints
int contextId1 = EverSdk.createDefault(); 
// creates default EVER-SDK with specified endpoint
int contextId2 = EverSdk.createWithEndpoint("http://localhost/graphql"); 
// creates EVER-SDK context from ready JSON string
int contextId4 = EverSdk.createWithJson(configJsonString);

Save your contextId, you will use this id to call EVER-SDK methods.

Configuring SDK with Builder

Alternatively, you can call EverSdk.builder() that provides builder methods for all config values of EVER-SDK. Thus you can easily configure only needed parts of library.

int contextId3 = EverSdk.builder()
                       .networkEndpoints("http://localhost/graphql")
                       .networkQueryTimeout(300_000L)
                       .build();

Calling EVER-SDK methods

It's very simple, just type ModuleName.methodName (list of modules and methods is here: EVER-SDK API Summary ). Note that method names are converted from snake_case to camelCase. Then pass EverSdkContext object as 1st parameter. That's all.

int contextId = TestEnv.newContextEmpty();
var asyncResult = Client.version(contextId);
var syncResult = EverSdk.await(asyncResult);
System.out.println("EVER-SDK Version: " + syncResult.version());

Notes

Custom EVER-SDK libs

EVER-SDK libs are included in the distribution, but if you want to use custom one - build EVER-SDK binary lib "ton_client"(.so/.dll) yourself (or get precompiled one)

Logging

java4ever-binding uses the JDK Platform Loggging (JEP 264: Platform Logging API and Service), so can be easily bridged to any logging framework.