Java计算String的SHA-1摘要的十六进制表示

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

public class SHA1Example {
    public static void main(String[] args) {
        String input = "Hello, world!";
        String sha1Hex = sha1Hex(input);
        System.out.println("SHA-1摘要（十六进制）: " + sha1Hex);
    }

    public static String sha1Hex(String input) {
        try {
            MessageDigest md = MessageDigest.getInstance("SHA-1");
            byte[] messageDigest = md.digest(input.getBytes(StandardCharsets.UTF_8));
            return bytesToHex(messageDigest);
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException(e);
        }
    }

    public static String bytesToHex(byte[] bytes) {
        StringBuilder hexString = new StringBuilder();
        for (byte b : bytes) {
            String hex = Integer.toHexString(0xff & b);
            if (hex.length() == 1) {
                hexString.append('0');
            }
            hexString.append(hex);
        }
        return hexString.toString();
    }
}