io.neow3j.contract.NeoToken Maven / Gradle / Ivy
package io.neow3j.contract;
import io.neow3j.contract.exceptions.UnexpectedReturnTypeException;
import io.neow3j.crypto.ECKeyPair.ECPublicKey;
import io.neow3j.protocol.Neow3j;
import io.neow3j.protocol.core.response.NeoAccountState;
import io.neow3j.protocol.core.stackitem.StackItem;
import io.neow3j.transaction.TransactionBuilder;
import io.neow3j.types.ContractParameter;
import io.neow3j.types.Hash160;
import io.neow3j.wallet.Account;
import java.io.IOException;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import static io.neow3j.types.ContractParameter.any;
import static io.neow3j.types.ContractParameter.hash160;
import static io.neow3j.types.ContractParameter.integer;
import static io.neow3j.types.ContractParameter.publicKey;
import static io.neow3j.types.StackItemType.ANY;
import static io.neow3j.types.StackItemType.ARRAY;
import static io.neow3j.types.StackItemType.BYTE_STRING;
import static io.neow3j.types.StackItemType.INTEGER;
import static io.neow3j.types.StackItemType.STRUCT;
import static java.util.Arrays.asList;
/**
* Represents the NeoToken native contract and provides methods to invoke its functions.
*/
public class NeoToken extends FungibleToken {
public static final String NAME = "NeoToken";
public static final Hash160 SCRIPT_HASH = calcNativeContractHash(NAME);
public static final int DECIMALS = 0;
public static final String SYMBOL = "NEO";
public static final BigInteger TOTAL_SUPPLY = new BigInteger("100000000");
private static final String UNCLAIMED_GAS = "unclaimedGas";
private static final String REGISTER_CANDIDATE = "registerCandidate";
private static final String UNREGISTER_CANDIDATE = "unregisterCandidate";
private static final String VOTE = "vote";
private static final String GET_CANDIDATES = "getCandidates";
private static final String GET_COMMITTEE = "getCommittee";
private static final String GET_NEXT_BLOCK_VALIDATORS = "getNextBlockValidators";
private static final String SET_GAS_PER_BLOCK = "setGasPerBlock";
private static final String GET_GAS_PER_BLOCK = "getGasPerBlock";
private static final String SET_REGISTER_PRICE = "setRegisterPrice";
private static final String GET_REGISTER_PRICE = "getRegisterPrice";
private static final String GET_ACCOUNT_STATE = "getAccountState";
/**
* Constructs a new {@code NeoToken} that uses the given {@link Neow3j} instance for
* invocations.
*
* @param neow the {@link Neow3j} instance to use for invocations.
*/
public NeoToken(Neow3j neow) {
super(SCRIPT_HASH, neow);
}
/**
* Returns the name of the NeoToken contract.
*
* Doesn't require a call to the Neo node.
*
* @return the name.
*/
@Override
public String getName() {
return NAME;
}
/**
* Returns the symbol of the NeoToken contract.
*
* Doesn't require a call to the Neo node.
*
* @return the symbol.
*/
@Override
public String getSymbol() {
return SYMBOL;
}
/**
* Returns the total supply of the NeoToken contract.
*
* Doesn't require a call to the Neo node.
*
* @return the total supply.
*/
@Override
public BigInteger getTotalSupply() {
return TOTAL_SUPPLY;
}
/**
* Returns the number of decimals of the NEO token.
*
* Doesn't require a call to the Neo node.
*
* @return the number of decimals.
*/
@Override
public int getDecimals() {
return DECIMALS;
}
// region unclaimed gas
/**
* Gets the amount of unclaimed GAS at the given height for the given account.
*
* @param account the account.
* @param blockHeight the block height.
* @return the amount of unclaimed GAS.
* @throws IOException if there was a problem fetching information from the Neo node.
*/
public BigInteger unclaimedGas(Account account, long blockHeight) throws IOException {
return unclaimedGas(account.getScriptHash(), blockHeight);
}
/**
* Gets the amount of unclaimed GAS at the given height for the given account.
*
* @param scriptHash the account's script hash.
* @param blockHeight the block height.
* @return the amount of unclaimed GAS
* @throws IOException if there was a problem fetching information from the Neo node.
*/
public BigInteger unclaimedGas(Hash160 scriptHash, long blockHeight) throws IOException {
ContractParameter accParam = hash160(scriptHash);
ContractParameter heightParam = integer(BigInteger.valueOf(blockHeight));
return callFuncReturningInt(UNCLAIMED_GAS, accParam, heightParam);
}
// endregion unclaimed gas
// region candidate registration
/**
* Creates a transaction script for registering a committee candidate with the given
* public key and initializes a {@link TransactionBuilder} based on this script.
*
* Note, that the transaction has to be signed with the account corresponding to the public key.
*
* @param candidateKey the public key to register as a candidate.
* @return a transaction builder.
*/
public TransactionBuilder registerCandidate(ECPublicKey candidateKey) {
return invokeFunction(REGISTER_CANDIDATE, publicKey(candidateKey.getEncoded(true)));
}
/**
* Creates a transaction script for registering a validator candidate and initializes a
* {@link TransactionBuilder} based on this script.
*
* @param candidateKey the public key to register as a candidate.
* @return a transaction builder.
*/
public TransactionBuilder unregisterCandidate(ECPublicKey candidateKey) {
return invokeFunction(UNREGISTER_CANDIDATE, publicKey(candidateKey.getEncoded(true)));
}
// endregion candidate registration
// region committee and candidates information
/**
* Gets the public keys of the current committee members.
*
* @return the committee members' public keys.
* @throws IOException if there was a problem fetching information from the
* Neo node.
* @throws UnexpectedReturnTypeException if the return type is not an array or the returned
* array's elements are not public keys.
*/
public List getCommittee() throws IOException {
return callFunctionReturningListOfPublicKeys(GET_COMMITTEE);
}
/**
* Gets the public keys of the currently registered validator candidates and their
* corresponding vote count.
*
* The vote count is based on the summed up NEO balances of the respective candidate's voters.
*
* @return the candidate public keys and their corresponding vote count.
* @throws IOException if there was a problem fetching information from the
* Neo node.
* @throws UnexpectedReturnTypeException if the return type is not an array or the array
* elements are not public keys and node counts.
*/
public Map getCandidates() throws IOException {
StackItem arrayItem = callInvokeFunction(GET_CANDIDATES)
.getInvocationResult().getStack().get(0);
if (!arrayItem.getType().equals(ARRAY)) {
throw new UnexpectedReturnTypeException(arrayItem.getType(), ARRAY);
}
Map validators = new HashMap<>();
for (StackItem valItem : arrayItem.getList()) {
if (!valItem.getType().equals(STRUCT)) {
throw new UnexpectedReturnTypeException(valItem.getType(), STRUCT);
}
ECPublicKey key = extractPublicKey(valItem.getList().get(0));
StackItem nrItem = valItem.getList().get(1);
if (!nrItem.getType().equals(INTEGER)) {
throw new UnexpectedReturnTypeException(nrItem.getType(), INTEGER);
}
validators.put(key, nrItem.getInteger());
}
return validators;
}
/**
* Checks if there is a committee candidate or member with {@code publicKey}.
*
* @param publicKey The candidates public key.
* @return true if the public key belongs to a candidate. False otherwise.
* @throws IOException if there was a problem fetching information from the Neo node.
*/
public boolean isCandidate(ECPublicKey publicKey) throws IOException {
return getCandidates().containsKey(publicKey);
}
/**
* Gets the public keys of the next block's validators.
*
* @return the validators' public keys.
* @throws IOException if there was a problem fetching information from the
* Neo node.
* @throws UnexpectedReturnTypeException if the return type is not an array or the returned
* array's elements are not public keys.
*/
public List getNextBlockValidators() throws IOException {
return callFunctionReturningListOfPublicKeys(GET_NEXT_BLOCK_VALIDATORS);
}
private List callFunctionReturningListOfPublicKeys(String function)
throws IOException {
StackItem arrayItem = callInvokeFunction(function).getInvocationResult().getStack().get(0);
if (!arrayItem.getType().equals(ARRAY)) {
throw new UnexpectedReturnTypeException(arrayItem.getType(), ARRAY);
}
List valKeys = new ArrayList<>();
for (StackItem keyItem : arrayItem.getList()) {
valKeys.add(extractPublicKey(keyItem));
}
return valKeys;
}
private ECPublicKey extractPublicKey(StackItem keyItem) {
if (!keyItem.getType().equals(BYTE_STRING)) {
throw new UnexpectedReturnTypeException(keyItem.getType(), BYTE_STRING);
}
try {
return new ECPublicKey(keyItem.getByteArray());
} catch (IllegalArgumentException e) {
throw new UnexpectedReturnTypeException("Byte array return type did not contain " +
"public key in expected format.", e);
}
}
// endregion committee and candidates information
// region voting
/**
* Creates a transaction script to vote for the given validators and initializes a
* {@link TransactionBuilder} based on this script.
*
* @param voter the account that casts the vote.
* @param candidate the candidate to vote for. If null, then the current vote of the voter is
* withdrawn (see {@link NeoToken#cancelVote(Account)}).
* @return a transaction builder.
* @throws IOException if there was a problem fetching information from the Neo node.
*/
public TransactionBuilder vote(Account voter, ECPublicKey candidate) throws IOException {
return vote(voter.getScriptHash(), candidate);
}
/**
* Creates a transaction script to vote for the given validators and initializes a
* {@link TransactionBuilder} based on this script.
*
* @param voter the account that casts the vote.
* @param candidate the candidate to vote for. If null, then the current vote of the voter is
* withdrawn (see {@link NeoToken#cancelVote(Hash160)}).
* @return a transaction builder.
* @throws IOException if there was a problem fetching information from the Neo node.
*/
public TransactionBuilder vote(Hash160 voter, ECPublicKey candidate) throws IOException {
if (candidate == null) {
return invokeFunction(VOTE, hash160(voter), any(null));
}
return invokeFunction(VOTE, hash160(voter), publicKey(candidate.getEncoded(true)));
}
/**
* Creates a transaction script to cancel the vote of {@code voter} and initializes a
* transaction Builder based on the script.
*
* @param voter the account for which to cancel the vote.
* @return a transaction builder
* @throws IOException if there was a problem fetching information from the Neo node.
*/
public TransactionBuilder cancelVote(Hash160 voter) throws IOException {
return vote(voter, null);
}
/**
* Creates a transaction script to cancel the vote of {@code voter} and initializes a
* transaction Builder based on the script.
*
* @param voter the account for which to cancel the vote.
* @return a transaction builder
* @throws IOException if there was a problem fetching information from the Neo node.
*/
public TransactionBuilder cancelVote(Account voter) throws IOException {
return cancelVote(voter.getScriptHash());
}
/**
* Builds a script to vote for a candidate.
*
* @param voter the account that casts the vote.
* @param candidate the candidate to vote for. If null, then the current vote of the voter is
* withdrawn (see {@link NeoToken#cancelVote(Hash160)}).
* @return the script.
*/
public byte[] buildVoteScript(Hash160 voter, ECPublicKey candidate) {
if (candidate == null) {
return buildInvokeFunctionScript(VOTE, hash160(voter), any(null));
}
return buildInvokeFunctionScript(VOTE, hash160(voter),
publicKey(candidate.getEncoded(true)));
}
// endregion voting
// region network settings
/**
* Gets the number of GAS generated in each block.
*
* @return the max GAS amount per block.
* @throws IOException if there was a problem fetching information from the Neo node.
*/
public BigInteger getGasPerBlock() throws IOException {
return callFuncReturningInt(GET_GAS_PER_BLOCK);
}
/**
* Creates a transaction script to set the number of GAS generated in each block and
* initializes a {@link TransactionBuilder} based on this script.
*
* This contract invocation can only be successful if it is signed by the network committee.
*
* @param gasPerBlock the maximum amount of GAS in one block.
* @return the transaction builder.
*/
public TransactionBuilder setGasPerBlock(BigInteger gasPerBlock) {
return invokeFunction(SET_GAS_PER_BLOCK, integer(gasPerBlock));
}
/**
* Gets the price to register as a candidate.
*
* @return the price to register as a candidate.
* @throws IOException if there was a problem fetching information from the Neo node.
*/
public BigInteger getRegisterPrice() throws IOException {
return callFuncReturningInt(GET_REGISTER_PRICE);
}
/**
* Creates a transaction script to set the price for candidate registration and initializes a
* {@link TransactionBuilder} based on this script.
*
* This contract invocation can only be successful if it is signed by the network committee.
*
* @param registerPrice the price to register as a candidate.
* @return the transaction builder.
*/
public TransactionBuilder setRegisterPrice(BigInteger registerPrice) {
return invokeFunction(SET_REGISTER_PRICE, integer(registerPrice));
}
// endregion network settings
/**
* Gets the state of an account.
*
* @param account the account to get the state from.
* @return the account state.
* @throws IOException if there was a problem fetching information from the Neo node.
*/
public NeoAccountState getAccountState(Hash160 account) throws IOException {
StackItem result = callInvokeFunction(GET_ACCOUNT_STATE, asList(hash160(account)))
.getInvocationResult().getStack().get(0);
if (result.getType().equals(ANY)) {
return NeoAccountState.withNoBalance();
}
List state = result.getList();
BigInteger balance = state.get(0).getInteger();
BigInteger updateHeight = state.get(1).getInteger();
StackItem publicKeyItem = state.get(2);
if (publicKeyItem.getType().equals(ANY)) {
return NeoAccountState.withNoVote(balance, updateHeight);
}
return new NeoAccountState(balance, updateHeight,
new ECPublicKey(publicKeyItem.getHexString()));
}
}