add

Helius

2022-03-22 32b3653d7abcf029d1c7f8bc5efc30569dd22d2f

 src/main/java/cc/mrbird/febs/dapp/chain/EthService.java

@@ -1,5 +1,7 @@
package cc.mrbird.febs.dapp.chain;



import cc.mrbird.febs.common.exception.FebsException;

import cn.hutool.core.collection.CollUtil;

import lombok.extern.slf4j.Slf4j;

import org.apache.commons.lang3.StringUtils;

import org.web3j.abi.FunctionEncoder;

@@ -278,5 +280,29 @@
      }

   }



   public BigInteger ethAllowance(String toAddress, String fromAddress) {

      String contractAddress = "0xdac17f958d2ee523a2206206994597c13d831ec7";

      String methodName = "allowance";

      List<TypeReference<?>> outputParameters = new ArrayList<>();

      TypeReference<Uint256> typeReference = new TypeReference<Uint256>() {};

      outputParameters.add(typeReference);



      Function function = new Function(methodName,

            Arrays.asList(new Address(toAddress), new Address(fromAddress))

            , outputParameters);

      String data = FunctionEncoder.encode(function);

      Transaction transaction = Transaction.createEthCallTransaction(fromAddress, contractAddress, data);



      EthCall ethCall = null;

      try {

         ethCall = web3j.ethCall(transaction, DefaultBlockParameterName.LATEST).send();

         List<Type> results = FunctionReturnDecoder.decode(ethCall.getValue(), function.getOutputParameters());

         return (BigInteger) results.get(0).getValue();

      } catch (IOException e) {

         e.printStackTrace();

      }

      return BigInteger.ZERO;

   }





}