Java4Ever is a feature-rich framework for smart-contracts development, testing & accessing TVM-compatible blockchains like Everscale, Venom, GOSH and so on. Closest alternative is a TypeScript-based locklift framework by Broxus.
Framework internally uses JSON-RPC connection to wrapped native EVER-SDK library (java4ever-binding).
- Auto-generation of Java smart contract wrappers to create, deploy, transact with and call smart contracts from native Java code
- Auto-conversion of ABI types to Java native types for any input/output
- Easy work with TIP 3.2 Fungible Tokens
- Easy work with Multisig Wallets
- Easy work with EverNode-SE Givers (with easy polymorph to giving from wallet on production)
- Access to transaction tree of complex calls
- Complete typed implementation of latest EVER-SDK JSON-RPC client API
- Pluggable EVER-SDK library support (no rebuild needed, just plug-in SDK lib you like with special Loaders)
Java4Ever only runtime dependencies are its own binding and utils libs and Jackson Core for fast JSON serialisation/deserialization It also uses JavaPoet for generating smart contract wrappers.
- Java4Ever
- Install JDK 22 (downloaded here)
- Install EverNode-SE (installation guide here)
- Install Kotlin 2.0.0
- Install Gradle 8.8
- Make sure to setup use of Gradle 8.8 and JDK 22 for compilation and runtime
Note: EverNode-SE needed only for quick start example, it's not a requirement
- Gradle
dependencies {
implementation 'tech.deplant.java4ever:java4ever-framework:3.2.0'
}- Maven
<dependency>
<groupId>tech.deplant.java4ever</groupId>
<artifactId>java4ever-framework</artifactId>
<version>3.2.0</version>
</dependency>// initialize EVER-SDK library
EverSdk.load();
// create config context, save its id
int contextId = EverSdk.createWithEndpoint("http://localhost/graphql").orElseThrow();
// creates random pair of keys
var keys = Credentials.ofRandom(contextId);
// use it to deploy a new contract
var contract = new SafeMultisigWalletTemplate()
.prepareDeploy(contextId,0, keys, new BigInteger[]{keys.publicKeyBigInt()}, 1)
.deployWithGiver(EverOSGiver.V2(contextId), EVER_ONE);
// get the contract info
System.out.println(contract.account().id() + " is active: " + contract.account().isActive());SDK setup consists of two steps:
- Loading EVER-SDK library (should be done once)
- Creating context/session with certain config (should be done for every new endpoint or config change)
Both steps are described below.
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")); 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.
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();Java4Ever includes easy API to work with files and java resources (both json-based and byte[]-based). Here are simple examples of getting contract ABIs and TVCs artifacts:
-
ContractAbi.ofFile("/path/to/your.abi.json")- reads abi from file (can be relative) -
ContractAbi.ofResource("yourresource.abi.json")- reads abi from resources of your project -
ContractAbi.ofString("")-reads abi from JSON string -
ContractAbi.ofJsonNode(node)- reads abi from Jackson framework's JsonNode object -
Tvc.ofFile("/path/to/your.tvc")- reads tvc from file (can be relative) -
Tvc.ofResource("yourresource.tvc")- reads tvc from resources of your project -
Tvc.ofBase64String("")-reads tvc from base64 encoded string -
new Tvc(bytes)- reads tvc from byte array
Also, you can check JsonFile, JsonResource, ByteFile, ByteResource helpers for custom artifacts.
Java4Ever includes basic helpers to create your seeds, key pairs and signatures. If you want some specific EVER-SDK functions, just use them firectly as all EVER-SDK API is available from Java4Ever.
var keys = Credentials.ofRandom(contextId);
String sk = keys.secretKey();
String pk = keys.publicKey();var seed = Seed.ofRandom(contextId);
String wordsPhrase = seed.phrase();
int wordsCount = seed.words();var keys = Credentials.ofSeed(contextId,seed);
String sk = keys.secretKey();
String pk = keys.publicKey();var keys = Credentials.ofSecret("17011c9157f3cf9e3c75ce8778be6b1adc42cd7abc1aebc0d288d2c338d2d93b");
String sk = keys.secretKey();
String pk = keys.publicKey();var seed = new Seed("your seed phrase with 12 words or 24 with second constructor param");
var keys = new Credentials("publickey_string","secretkey_string");int context = EverSdk.createDefault();
var keys = Env.RNG_KEYS();
// create implementation of your handle
var boxHandle = EverSdk.await(Crypto.registerSigningBox(context, new AppSigningBox() {
@Override
public String getPublicKey() {
return "";
}
@Override
public String sign(String unsigned) {
return "";
}
})).handle();
// use this handle when creating contract object
var contract = new EverWalletContract(context,
new Address("0:9400ec4b8629b5293bb6798bbcf3dd25d72e4f114226b5547777d0fc98fe53fa"),
new Abi.Signer.SigningBox(boxHandle));
// now contract calls will use your signing box
contract.sendTransaction(dest, value, bounce).call();// to use already deployed contract, you should know its ABI and its address
var deployedContractAbi = ContractAbi.ofResource("artifacts/giver/GiverV2.abi.json");
var deployedContractAddress = new Address("0:ece57bcc6c530283becbbd8a3b24d3c5987cdddc3c8b7b33be6e4a6312490415");
// if you don't know contract credentials, use Credentials.NONE
var deployedContractCredentials = new Credentials("2ada2e65ab8eeab09490e3521415f45b6e42df9c760a639bcf53957550b25a16",
"172af540e43a524763dd53b26a066d472a97c4de37d5498170564510608250c3");
// instantiate your contract
var giverContract = new AbstractContract(contextId,
deployedContractAddress,
deployedContractAbi,
deployedContractCredentials);
// make a call by function name
var functionCallPrepare = giverContract.functionCallBuilder()
.setFunctionName("getMessages")
.setFunctionInputs(Map.of()) // provide a map of params
.setReturnClass(Map.class)
.build();
// if you didn't provide return class, use callAsMap() and getAsMap() to receive plain JSON
System.out.println(functionCallPrepare.getAsMap().toPrettyString());If you don't want to write function calls by hand, use Contract Generation tips below to generate your own Contract classes.
To access account metadata of certain smart-contract, get Account object from any type of Contract
Account acc = contract.account();Alternatively, you can create Account object from any address
Account acc = Account ofAddress(contextId, "0:ece57bcc6c530283becbbd8a3b24d3c5987cdddc3c8b7b33be6e4a6312490415");Then, get all needed info from account
acc.boc();
acc.code();
acc.codeHash();
acc.balance();
acc.accType();ContractWrapper class is a generator that will create java wrapper
classes for all your contracts. You need only abi.json and .tvc
artifacts of your contracts as a source for code generation.
Run the following, specifying your artifacts and where to place generated classes in params:
ContractWrapper.generate(ContractAbi.ofResource("mycontract.abi.json").abiContract(),
Tvc.ofResource("mycontract.tvc"),
Path.of("src/gen/java"),
"MyContract",
"org.example.contract",
"org.example.template",
new String[]{});Contract and template wrappers will appear in packages that you specified.
If you're working with standard contracts, all wrappers are already generated (for Multisig Wallets, Givers, TIP3 and TIP4 contracts and so on - check javadoc)
To access contract account, create instance of your contract class by passing SDK Provider and address of deployed contract.
MyContract contr = new MyContract(contextId, "0:your_contract_address");Now, when your contract object is created, just get handle of one of functions by calling one of the contract methods.
FunctionHandle getCustodiansFunctionHandle = contr.getCustodians();Function in this example doesn't have params, but yours can have.
With FunctionHandle you can make external calls, run get methods using remote or local boc and so on like this:
MyContract.ResultOfGetCustodians custodians = getCustodiansFunctionHandle.get();
Map<String,Object> custodiansMap = getCustodiansFunctionHandle.getAsMap();
MyContract.ResultOfGetCustodians custodians = getCustodiansFunctionHandle.call();
Map<String,Object> custodiansMap = getCustodiansFunctionHandle.callAsMap();
MyContract.ResultOfGetCustodians custodians = getCustodiansFunctionHandle.getLocal(locallySavedBoc);All the described functions, handles and return types are auto-generated when you generate contract wrapper
Variants of calls to function:
- get() - runs getter method and returns auto-generated type
- call() - makes external call (make sure you added credentials to contract object if contract checks signatures)
- getLocal() - runs getter against provided boc
- ...AsMap() - each method have AsMap variant that returns Jackson framework's JsonNode object instead of static type result
Second class created by contract generator is MyContractTemplate.class.
It's a companion class that stores ABI and TVC info for deployment.
var walletContract = new SafeMultisigWallet(contextId,"", walletKeys);
getCustodiansFunctionHandle.sendFrom(walletContract, CurrencyUnit.VALUE(EVER,"1.25"), true, MessageFlag.FEE_EXTRA);sendFrom() method also has sendFromAsMap() variant.
Calls and sends also has ...Tree() variants that can be used to monitor transaction tree execution and collect errors.
You can encode FunctionHandle as a payload for internal call like this:
var payload = getCustodiansFunctionHandle.toPayload();java4ever supports all popular types of Multisig contracts. You can check if it's your needed smart-contract by retrieving its code hash.
// multisig 1
assertEquals("80d6c47c4a25543c9b397b71716f3fae1e2c5d247174c52e2c19bd896442b105",
SafeMultisigWalletTemplate.DEFAULT_TVC().codeHash(contextId));
assertEquals("e2b60b6b602c10ced7ea8ede4bdf96342c97570a3798066f3fb50a4b2b27a208",
SetcodeMultisigWalletTemplate.DEFAULT_TVC().codeHash(contextId));
assertEquals("207dc560c5956de1a2c1479356f8f3ee70a59767db2bf4788b1d61ad42cdad82",
SurfMultisigWalletTemplate.DEFAULT_TVC().codeHash(contextId));
// multisig 1 with modern compiler
assertEquals("1974b06efa89ba22d1962d06efaef6d00751b7cdc3156c151bb0cc1c504e7e8c",
SafeMultisigSolc064WalletTemplate.DEFAULT_TVC().codeHash(contextId));
assertEquals("ad57a772ca0c56462e07a086e447abbb7605bd6ac1424cc4178dc9f4730093ff",
SetcodeMultisigSolc063WalletTemplate.DEFAULT_TVC().codeHash(contextId));
// multisig 2
assertEquals("7377910a1b5d0c8073ba02523e139c7f42f9772fe0076a4d0b211ccec071eb7a",
SafeMultisigWallet2Template.DEFAULT_TVC().codeHash(contextId));
assertEquals("d66d198766abdbe1253f3415826c946c371f5112552408625aeb0b31e0ef2df3",
SetcodeMultisigWallet2Template.DEFAULT_TVC().codeHash(contextId));
// multisig 24
assertEquals("7d0996943406f7d62a4ff291b1228bf06ebd3e048b58436c5b70fb77ff8b4bf2",
Safe24MultisigWalletTemplate.DEFAULT_TVC().codeHash(contextId));
assertEquals("a491804ca55dd5b28cffdff48cb34142930999621a54acee6be83c342051d884",
Setcode24MultisigWalletTemplate.DEFAULT_TVC().codeHash(contextId));
// specials
assertEquals("f3a07ae84fc343259d7fa4847b86335b3fdcfc8b31f1ba4b7a9499d5530f0b18",
BridgeMultisigWalletTemplate.DEFAULT_TVC().codeHash(contextId));java4ever supports TIP3TokenRootContract and TIP3TokenWalletContract. Also, TIP3Builder is available for specifying token parameters builder-style. Here is a quick example of working with TIP-3:
// creating token Root
var tokenRoot = new TIP3Builder()
.setRootKeys(LOCAL_KEYS_ROOT)
.setOwnerAddress(LOCAL_MSIG_ROOT.address())
.setName("Test Token")
.setSymbol("TST")
.setDecimals(6)
.setRandomNonce(new Random().nextInt())
.build(SDK_LOCAL, GIVER_LOCAL, CurrencyUnit.VALUE(EVER, "1.3"));
// deploying token wallet
tokenRoot.deployWallet(LOCAL_MSIG_WALLET1.address(),
CurrencyUnit.VALUE(EVER, "0.5"))
.sendFrom(LOCAL_MSIG_ROOT,
CurrencyUnit.VALUE(EVER, "1.5"));
// mint operation
tokenRoot.mint(mintAmount, receiverAddress, EVER_ZERO, receiverAddress, false,
TvmCell.EMPTY)
.sendFromTree(LOCAL_MSIG_ROOT,
CurrencyUnit.VALUE(EVER, "0.3"),
true,
MessageFlag.FEE_EXTRA,
true,
TIP3TokenWalletContract.DEFAULT_ABI());
// getters
assertEquals(mintAmount, tokenRoot.totalSupply().get().value0());
assertEquals(mintAmount, tokenRoot.balance().get().value0());java4ever provides TIP4Collection, TIP4IndexBasis,
TIP4Index, TIP4Nft and TIP4Wallet templates and contract wrappers.
You can create template object with no additional params.
If you didn't use generator, use AbstractTemplate class and
pass ABI and TVC to it manually.
MyContractTemplate myTemplate = new MyContractTemplate();
var abi = myTemplate.abi(); // getting ABI from template
var tvc = myTemplate.tvc(); // getting TVC from template
myTemplate.tvc().code() // getting code cell
myTemplate.tvc().codeHash() // getting code hashThere are much more methods for TVC and ABI, including decoding and encoding initial data, various helpers for all sort of interactions.
DeployHandle is a handle of prepared deployment set with all needed params.
As with function handles, Template::prepareDeploy params may vary depending on your contract -
your static variables and constructor params.
DeployHandle deployHandle = myTemplate.prepareDeploy(contextId, Credentials.NONE,"hello_world");// Deploys prepared contract deployment. Will work only when deploy target account address is already paid
// You can check target account address by using deployHandle.toAddress() call
MyContract myContract = deployHandle.deploy();
// deploys prepared contract deployment by using funds from specified wallet
MyContract myContract = deployHandle.deployWithGiver(walletContract, CurrencyUnit.VALUE(EVER,"1.25"));
// deploys prepared contract deployment by using funds from EverNode-SE giver
MyContract myContract = deployHandle.deployWithGiver(EverOSGiver.V2(contextId), CurrencyUnit.VALUE(EVER,"1.25"));Each deployment returns a contract object after deploy is done.
Also, you can use deployHandle.toAddress() if you need only address calculation.
Deployment usually requires giving funds to target address of deployment. Here's the example of universal deployment that switches between evernode-se giver & msig wallet without any additional code:
Giver giver = null;
if (isEverOsNet()) {
giver = EverOSGiver.V2(contextId);
} else {
giver = new SafeMultisigWallet(contextId,"0:your_address");
}
deployHandle.deployWithGiver(giver, CurrencyUnit.VALUE(EVER,"1.25"));This is possible as all Java4Ever wallet classes are implementing Giver interface. You can also generate wrappers that implements Giver interface.
Example of creation and signing offline messages for later sending.
int offlineContext = EverSdk.builder()
.networkSignatureId(1L)
.networkQueryTimeout(300_000L)
.build();
int i = 0;
var template = new EverWalletTemplate();
// let's generate 5 addresses that match certain condition and send them 1 ever
Predicate<Address> addressCondition = address -> address.makeAddrStd().contains("7777");
while (i < 5) {
var seed = Env.RNG_SEED(); // creates new seed
var keys = seed.deriveCredentials(offlineContext); // derives keys from seed
// let's calculate future EVER Wallet address
var stateInit = template.getStateInit(offlineContext, keys.publicKey(), BigInteger.ZERO);
var address = template.getAddress(offlineContext, 0, stateInit);
// check conditions if we want to deploy contract
if (addressCondition.test(address)) {
// let's create message bodies offline
// here we send sendTransaction to ourselves
var body = new EverWalletContract(offlineContext, address, keys).sendTransaction(address, EVER_ONE, false)
.toPayload(false);
System.out.printf("Address: %s%n", address);
System.out.printf("Seed: %s, public: %s%n", seed.phrase(), keys.publicKey());
System.out.printf("Message body: %s%n", body);
System.out.printf("State Init: %s%n", stateInit);
int onlineContext = EverSdk.createWithEndpoint("https://gql.venom.foundation/graphql");
// let's send messages when we're online
EverSdk.sendExternalMessage(onlineContext,
address.makeAddrStd(),
EverWalletTemplate.DEFAULT_ABI().ABI(),
stateInit.cellBoc(),
body.cellBoc(),
null);
i++;
}
}Unstable - Subscriptions were heavily changed in the last release, so there can be dragons.
Subscriptions consist of Subscription.Builder class where you describe your subscription details. After that, run the subscription with subscribe..() methods. Subscription supports sprcifying multiple GQL filters, multiple consumers, saving to queue, manual and auto-unsubscribing on condition.
// let's specify what will consume our event:
Consumer<JsonNode> eventConsumer = jsonNode -> System.out.println(jsonNode.toPrettyString());
// describe our subscription in builder style
var subscriptionBuilder = Subscriptions
.onAccounts("acc_type", "id")
.addFilterOnSubscription("id: { eq: \"<your_address>\" }")
.addFilterOnSubscription("code_hash: { eq: \"<your_hash>\" }")
.addCallbackConsumer(eventConsumer)
.setCallbackToQueue(true); // if you don't want to specify consumer, you can switch on adding to internal queue
// let's subsribe
var subscription1 = subscriptionBuilder.subscribeUntilCancel(1);
// let's unsubscribe
subscription1.unsubscribe();
// perhaps some messages were pu in the queue?
int size = subscription1.callbackQueue().size();
// let's reuse builder, but subscribe until first event is fired
var subscription2 = subscriptionBuilder.subscribeUntilFirst(1);
// another one, subscribed until certain condition
var subscription3 = subscriptionBuilder.subscribeUntilCondition(1, jsonNode -> !jsonNode.get("accounts").elements().hasNext());All solidity currency constants are available from CurrencyUnit class. You can retrieve final bigint about like this
var everAmount = CurrencyUnit.VALUE(EVER, "2"); // 2_000_000_000 nanoevers
var everAmount = CurrencyUnit.VALUE(MILLIEVER, "500.3"); // 500_300_000 nanoeversIf your token has custom decimals count, you can specify it like this
var tokenUnit = new CurrencyUnit.CustomToken(12); // my token has 12 decimals
// then use your own tokenunits in all your calls
var nanoValue = CurrencyUnit.VALUE(tokenUnit, "2.2"); // 2_200_000_000_000 nanotokensJava4Ever uses the JDK Platform Loggging (JEP 264: Platform Logging API and Service),
so can be easily bridged to any logging framework. For example, to use log4j2, just add org.apache.logging.log4j:log4j-jpl to your Maven/Gradle build.
If you can't answer in this readme or have a bug/improvement to report: