### Question:
EthSendTransactionJsonParameters { public String sender() { return sender; } @JsonCreator  EthSendTransactionJsonParameters(@JsonProperty("from") final String sender); @JsonSetter("gas") void gas(final String gas); @JsonSetter("gasPrice") void gasPrice(final String gasPrice); @JsonSetter("nonce") void nonce(final String nonce); @JsonSetter("to") void receiver(final String receiver); @JsonSetter("value") void value(final String value); @JsonSetter("data") void data(final String data); Optional<String> data(); Optional<BigInteger> gas(); Optional<BigInteger> gasPrice(); Optional<String> receiver(); Optional<BigInteger> value(); Optional<BigInteger> nonce(); String sender();  }### Answer:
@Test public void transactionWithInvalidFromCanBeDecoded() { final JsonObject parameters = validEthTransactionParameters(); parameters.put("from", "invalidFromAddress"); final JsonRpcRequest request = wrapParametersInRequest(parameters); final EthSendTransactionJsonParameters txnParams = factory.fromRpcRequestToJsonParam(EthSendTransactionJsonParameters.class, request); assertThat(txnParams.sender()).isEqualTo("invalidFromAddress"); }