问题
I am returning an array of struct from solidity function as below.
pragma solidity ^0.4.21;
pragma experimental ABIEncoderV2;
function getPurchaseOrderForVendor(string vendorNameInput) constant returns (PurchaseOrderStruct[])
It is compiled to abi and bin files. The issue is with creating wrapper files for the contract using web3j(v3.3.1). Im getting the below errors.
Generating com.contract.InvoiceSettlement_sol_InvoiceSettlement ...
Exception in thread "main" java.lang.UnsupportedOperationException:
Unsupported type
encountered: tuple
at org.web3j.abi.datatypes.generated.AbiTypes.getType(AbiTypes.java:221)
at org.web3j.codegen.SolidityFunctionWrapper.buildTypeName(SolidityFunct
ionWrapper.java:851)
at org.web3j.codegen.SolidityFunctionWrapper.buildTypeNames(SolidityFunc
tionWrapper.java:508)
at org.web3j.codegen.SolidityFunctionWrapper.buildFunction(SolidityFunct
ionWrapper.java:523)
at org.web3j.codegen.SolidityFunctionWrapper.buildFunctionDefinitions(So
lidityFunctionWrapper.java:216)
at org.web3j.codegen.SolidityFunctionWrapper.generateJavaFiles(SolidityF
unctionWrapper.java:112)
at org.web3j.codegen.SolidityFunctionWrapper.generateJavaFiles(SolidityF
unctionWrapper.java:94)
at org.web3j.codegen.SolidityFunctionWrapperGenerator.generate(SolidityF
unctionWrapperGenerator.java:123)
at org.web3j.codegen.SolidityFunctionWrapperGenerator.main(SolidityFunct
ionWrapperGenerator.java:87)
at org.web3j.codegen.SolidityFunctionWrapperGenerator.run(SolidityFuncti
onWrapperGenerator.java:48)
at org.web3j.console.Runner.main(Runner.java:38)
回答1:
Solidity does not support returning structs in external calls. It is only allowed in internal function calls. You need to decompose the struct and return the elements via a tuple.
Source: Solidity documentation
来源：https://stackoverflow.com/questions/49428518/web3j-v3-3-1-error-while-generating-compiled-solidity-smart-contracts-which-re