Java基于secp256k1生成公私钥对

```
/**
 *  secp256k1 加解密
 *  <see>https://www.xfqiao.com/api/android-zh/java/security/KeyPairGenerator.html</see>
 *  <see>https://docs.oracle.com/javase/8/docs/api/java/security/KeyPairGenerator.html</see>
 * @author
 * @date 2022年11月23日21:37:46
 */
public class KeyPairUtil {

    /**
     * 生成 公钥 私钥 对
     * @param stdName  eg: secp256k1
     * @return
     * @throws NoSuchAlgorithmException
     * @throws InvalidAlgorithmParameterException
     */
    public static KeyPair createKeyPairGenerator(String stdName) throws NoSuchAlgorithmException, InvalidAlgorithmParameterException {
        // 生成秘钥，在实际业务中，应该加载秘钥
        KeyPairGenerator kpg = KeyPairGenerator.getInstance("EC");

        ECGenParameterSpec m = new ECGenParameterSpec(stdName);

        kpg.initialize(m);

        KeyPair keyPair = kpg.generateKeyPair();
        return  keyPair;
    }

    /**
     * 签名
     * @param algorithm
     * @param data
     * @param key
     * @return
     * @throws Exception
     */
    public static byte[] sign(String algorithm, byte[] data, PrivateKey key) throws Exception {
        Signature signer = Signature.getInstance(algorithm);
        signer.initSign(key);
        signer.update(data);
        return (signer.sign());
    }

    /**
     * 验签
     * @param algorithm
     * @param data
     * @param key
     * @param sig
     * @return
     * @throws Exception
     */
    public static boolean verifySign(String algorithm, byte[] data, PublicKey key, byte[] sig) throws Exception {
        Signature signer = Signature.getInstance(algorithm);
        signer.initVerify(key);
        signer.update(data);
        return (signer.verify(sig));
    }
}
```