Js 코드를 java 로 바꾸고싶네요

await caver.klay.accounts
      .signTransaction(
        {
          from: owner.address,
          to: heroProxyAddress,
          nonce: heroNonce,
          gas: 5000000,
          data: heroInstance.mintByOwner().encodeABI(),
        },
        owner.privateKey
      )
      .then(async (Tx) => {
        caver.klay
          .sendSignedTransaction(Tx.rawTransaction)
          .then((hash, err) => {
            if (err) console.log(err);
            else {
              console.log("Make NFT By Owner To Hero");
            }
          });
      });

해당 js 코드를 caver-java 로 만든다면 어찌 포팅될지 궁금합니다…