web3j

1.根据私钥获取密钥

public static void main(String[] args) {

        String priKey = "45e62c6b91ae6bc0e1a69ba630eea7ad50ef42411358b3c4784c0da01092423a";
        String pubKey = "0207c200b9751a48313ee8e5fd01c9925659d290abd6e0dbfbdef73f518af560cc";

        Credentials credentials = Credentials.create(priKey);
        BigInteger publicKey = credentials.getEcKeyPair().getPublicKey();

        Long l = System.currentTimeMillis();

        String s = l.toString();
        Sign.SignatureData signMessage = Sign.signMessage(s.getBytes(), credentials.getEcKeyPair());

        System.out.println("公钥：" + publicKey);
        System.out.println("地址：" + credentials.getAddress());
        System.out.println("content" + s);
        System.out.println("0x" + Hex.toHexString(signMessage.getR()) + Hex.toHexString(signMessage.getS()) + Hex.toHexString(signMessage.getV()));
    }```


private boolean verifySignResult(String userPublicKey, String content, String signature) {
        // 公钥去解析密文
        byte[] bytes = Hash.sha3(content.getBytes());
//        byte[] loginHashBytes = Hex.decode(content);
//        byte[] messageHash = Sign.getEthereumMessageHash(loginHashBytes);

        //还原r,s,v
        byte[] r = Hex.decode(signature.substring(2, 66));
        byte[] s = Hex.decode(signature.substring(66, 130));
        byte[] v = Hex.decode(signature.substring(130, 132));

        Sign.SignatureData signatureData = new Sign.SignatureData(v, r, s);

        //获得被签名的原文
        String publicKey = null;
        try {
            publicKey = Sign.signedMessageHashToKey(bytes, signatureData).toString();
        } catch (SignatureException e) {
            e.printStackTrace();
        }

        //还原时间戳原文
//        String timeStamp = bigInteger.toString();
        //还原时间戳
//        log.info("timeStamp={}", timeStamp);
        return userPublicKey.equals(publicKey);
    }

private static boolean verify(String userPublicKey, String content, String signature) {
        byte[] s = Hash.sha3(content.getBytes());
        byte[] bytes = Numeric.hexStringToByteArray(signature);
        byte v = bytes[64];
        if (v < 27) {
            v += 27;
        }
        Sign.SignatureData signatureData = new Sign.SignatureData(v, Arrays.copyOfRange(bytes, 0, 32),
                Arrays.copyOfRange(bytes, 32, 64));
        boolean match = false;
        for (int i = 0; i < 4; i++) {
            BigInteger publicKey = Sign.recoverFromSignature(
                    (byte) i,
                    new ECDSASignature(new BigInteger(1, signatureData.getR()), new BigInteger(1, signatureData.getS())),
                    s);
            if (publicKey != null) {
                match = userPublicKey.equals(publicKey.toString());
                if (match) {
                    return match;
                }
            }
        }
        return match;
    }