Version 1.0.0
English / 中文
The storing of Digital Assets such as ONT and ONG is handled by the Java SDK using the Account structure, which is outlined below.
address Base58 encoded account address
label Name of account
isDefaultIndicates whether the account is the default
lock Indicates whether the account is locked by the client user - Locked accounts can't spend
algorithm Name of the encryption algorithm used
parameters Encryption parameters
curve Elliptic curve used
key NEP-2 private key - whose value can be null in case of read-only or non-standard addresses
contract Smart contract hash - whose value can be null in case of read-only addresses
encAlg Private key encryption algorithm name - fixed at aes-256-ctr
salt Private key decryption salt
extra Extra information stored by client developer - value can be null
signatureScheme signatureScheme Signature scheme used for transaction signatures
hash Hash algorithm for derived privateKey
public class Account {
public String label = "";
public String address = "";
public boolean isDefault = false;
public boolean lock = false;
public String algorithm = "";
public Map parameters = new HashMap() ;
public String key = "";
@JSONField(name = "enc-alg")
public String encAlg = "aes-256-gcm";
public String salt = "";
public String hash = "sha256";
public String signatureScheme = "SHA256withECDSA";
public Object extra = null;
}
The following code shows some common digital asset functions:
- Create digital asset account
OntSdk ontSdk = OntSdk.getInstance();
Account acct = ontSdk.getWalletMgr().createAccount("password");
//any account or identity, once created is stored in memory only. A write api should be invoked to write to a wallet file.
ontSdk.getWalletMgr().writeWallet();
- Remove digital asset account
ontSdk.getWalletMgr().getWallet().removeAccount(address);
//write to wallet
ontSdk.getWalletMgr().writeWallet();
- Set default digital asset account
ontSdk.getWalletMgr().getWallet().setDefaultAccount(index);
ontSdk.getWalletMgr().getWallet().setDefaultAccount("address");
Note:
index: The account with such index number is set as the default account.
address: The account with such address is set as the default account.
Methods apply to both ONT and ONG assets.
sendTransfer
String sendTransfer (Account sendAcct, String recvAddr, long amount, Account payerAcct, long gaslimit, long gasprice)
Function description: Transfer a certain amount of assets from the sender to the receiver's account.
Parameters:
sendAcct: Sender account
recvAddr: Receiver address
amount: Asset amount
payerAcct: Payment transaction account
gaslimit: Gas limit
gasprice: Gas price
return value: Transaction hash
sendApprove
String sendApprove (Account sendAcct, String recvAddr, long amount, Account payerAcct, long gaslimit, long gasprice)
Function description: SendAcct account allows recvAddr to transfer amount of assets.
Parameters:
sendAcct: Sender account
recvAddr: Receive address
amount: Asset amount
payerAcct: Payment transaction account
gaslimit: Gas limit
gasprice: Gas price
return value: Transaction hash
sendTransferFrom
String sendTransferFrom (Account sendAcct, String fromAddr, String toAddr, long amount, Account payerAcct, long gaslimit, long gasprice)
Function description: The sendAcct account transfers the amount of assets from the fromAddr account to the toAddr account.
Parameters:
sendAcct: Sender account
fromAddr: From address
toAddr: Receive address
amount: Asset amount
payerAcct: Payment transaction account
gaslimit: Gas limit
gasprice: Gas price
return value: Transaction hash
queryBalanceOf
long queryBalanceOf (String address)
Function description: Query the asset balance of the account address.
Parameters:
address：Account address
return value： Balance of address
queryAllowance
long queryAllowance (String fromAddr,String toAddr)
Function description: Query balance of the account address.
Parameters:
fromAddr: From address
toAddr: To address
return value: Asset amount
queryName
String queryName()
Function description: Query asset name information.
return value: Asset name detail information
querySymbol
String querySymbol
Function description: Query asset symbol information.
return value：Symbol information
queryDecimals
long queryDecimals()
Function description: Query the accuracy of assets
return value：decimal
queryTotalSupply
long queryTotalSupply()
Function description： Query the total supply of assets
return value：total Supply
//get sdk instance
OntSdk sdk = OntSdk.getInstance();
sdk.setRpc(url);
sdk.openWalletFile("OntAssetDemo.json");
//get ontAssetTx instance
ont = sdk.nativevm().ont()
//transfer
com.github.ontio.account.Account account1 = new com.github.ontio.account.Account(privateKey,SignatureScheme.SHA256WITHECDSA);
ont.sendTransfer(account1,"TA4pCAb4zUifHyxSx32dZRjTrnXtxEWKZr",10000,account1,ontSdk.DEFAULT_GAS_LIMIT,0);
NEP-5 document：
https://github.com/neo-project/proposals/blob/master/nep-5.mediawiki
Digital assets template:
https://github.com/neo-project/examples/tree/master/ICO_Template
| Function | Params | Returns | Description |
|---|---|---|---|
| sendInit | boolean preExec | String | If true, it indicates that the pre-execution is to test whether it has been initialized. If it is false, the contract parameters are initialized. |
| sendTransfer | String sendAddr, String password, String recvAddr, int amount | String | Transfer assets |
| sendBalanceOf | String addr | String | Get account balance |
| sendTotalSupply | String | Get total supply | |
| sendName | String | Get name | |
| sendDecimals | String | Get accuracy | |
| sendSymbol | String | Query token abbreviation |
using Neo.SmartContract.Framework;
using Neo.SmartContract.Framework.Services.Neo;
using Neo.SmartContract.Framework.Services.System;
using System;
using System.ComponentModel;
using System.Numerics;
namespace Nep5Template
{
public class Nep5Template : SmartContract
{
//Token Settings
public static string Name() => "Nep5Template Token";
public static string Symbol() => "TMP";
public static readonly byte[] community = "AXK2KtCfcJnSMyRzSwTuwTKgNrtx5aXfFX".ToScriptHash();
public static byte Decimals() => 8;
private const ulong factor = 100000000; //decided by Decimals()
//ICO Settings
private const ulong totalAmount = 1000000000 * factor;
private const ulong communityCap = 1000000000 * factor;
[DisplayName("transfer")]
public static event Action<byte[], byte[], BigInteger> Transferred;
public static Object Main(string operation, params object[] args)
{
if (Runtime.Trigger == TriggerType.Application)
{
if (operation == "init") return Init();
if (operation == "totalSupply") return TotalSupply();
if (operation == "name") return Name();
if (operation == "symbol") return Symbol();
if (operation == "transfer")
{
if (args.Length != 3) return false;
byte[] from = (byte[])args[0];
byte[] to = (byte[])args[1];
BigInteger value = (BigInteger)args[2];
return Transfer(from, to, value);
}
if (operation == "balanceOf")
{
if (args.Length != 1) return 0;
byte[] account = (byte[])args[0];
return BalanceOf(account);
}
if (operation == "decimals") return Decimals();
}
return false;
}
// init
public static bool Init()
{
byte[] total_supply = Storage.Get(Storage.CurrentContext, "totalSupply");
if (total_supply.Length != 0) return false;
Storage.Put(Storage.CurrentContext, community, communityCap);
Transferred(null, community, communityCap);
Storage.Put(Storage.CurrentContext, "totalSupply", totalAmount);
return true;
}
// get the total token supply
// Get the total number of issued tokens
public static BigInteger TotalSupply()
{
Runtime.CheckSig(new byte[1]{ 1 }, new byte[]{2},new byte[]{ 3});
return Storage.Get(Storage.CurrentContext, "totalSupply").AsBigInteger();
}
// function that is always called when someone wants to transfer tokens.
// transfer token
public static bool Transfer(byte[] from, byte[] to, BigInteger value)
{
if (value <= 0) return false;
if (!Runtime.CheckWitness(from)) return false;
if (from == to) return true;
BigInteger from_value = Storage.Get(Storage.CurrentContext, from).AsBigInteger();
if (from_value < value) return false;
if (from_value == value)
Storage.Delete(Storage.CurrentContext, from);
else
Storage.Put(Storage.CurrentContext, from, from_value - value);
BigInteger to_value = Storage.Get(Storage.CurrentContext, to).AsBigInteger();
Storage.Put(Storage.CurrentContext, to, to_value + value);
Transferred(from, to, value);
return true;
}
// get the account balance of another account with address
// Get the token's balance based on the address
public static BigInteger BalanceOf(byte[] address)
{
return Storage.Get(Storage.CurrentContext, address).AsBigInteger();
}
}
}