Bad performance HmacSM3Signer#hash

Source file: https://github.com/aliyun/aliyun-openapi-java-sdk/blob/master/aliyun-java-sdk-core/src/main/java/com/aliyuncs/auth/signers/HmacSM3Signer.java

new BouncyCastleProvider() is very heavy, BouncyCastleProvider should use as singleton, here is the simple benchmark test code:

import org.bouncycastle.jce.provider.BouncyCastleProvider;

import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Base64;

public class Tt {

    public static void main(String[] args) throws NoSuchAlgorithmException, InterruptedException {
        long t1 = System.currentTimeMillis();
        for (int i = 0; i < 1000; i++) {
            String digest = Base64.getEncoder().encodeToString(hash("test".getBytes(StandardCharsets.UTF_8)));
            AssertUtil.isTrue("VeEukWUNL+xW7HTh0+Tdv84u86ZYkMKhns+IowfnaiM=".equals(digest));
        }
        System.out.println((System.currentTimeMillis() - t1) + " ms");

        long t2 = System.currentTimeMillis();
        for (int i = 0; i < 1000; i++) {
            String digest = Base64.getEncoder().encodeToString(hash2("test".getBytes(StandardCharsets.UTF_8)));
            AssertUtil.isTrue("VeEukWUNL+xW7HTh0+Tdv84u86ZYkMKhns+IowfnaiM=".equals(digest));
        }
        System.out.println((System.currentTimeMillis() - t2) + " ms");
    }

    private static String HASH_SM3 = "SM3";
    private static BouncyCastleProvider PROVIDER = new BouncyCastleProvider();

    public static byte[] hash(byte[] raw) throws NoSuchAlgorithmException {
        if (null == raw) {
            return null;
        }
        BouncyCastleProvider provider = new BouncyCastleProvider();
        MessageDigest digest = MessageDigest.getInstance(HASH_SM3, provider);
        return digest.digest(raw);
    }

    public static byte[] hash2(byte[] raw) throws NoSuchAlgorithmException {
        if (null == raw) {
            return null;
        }
        MessageDigest digest = MessageDigest.getInstance(HASH_SM3, PROVIDER);
        return digest.digest(raw);
    }
}

Outputs:

2760 ms
4 ms

The affected source is aliyun-java-sdk-core/src/main/java/com/aliyuncs/auth/signers/HmacSM3Signer.java. Start by reading HmacSM3Signer#hash and compare its provider construction with the singleton approach in the supplied benchmark. Done means preserving the expected SM3 digest while avoiding repeated BouncyCastleProvider construction and confirming the performance difference with the benchmark.