Sha1Test.java

package dev.blucobalt;


import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Locale;

/**
 * @author luke
 * Date: 2021/01/12
 */
public class Sha1Test
{
    public static void main(String[] args)
            throws NoSuchAlgorithmException, IOException
    {
        File test = new File("C:\\Users\\Lukes\\IdeaProjects\\nativetest\\TestFile.txt");
        System.out.println(getSha1(test));
    }
    
    // credit goes to https://gist.github.com/zeroleaf/6809843 for this
    public static String getSha1(File path)
            throws NoSuchAlgorithmException, IOException
    {
        MessageDigest md = MessageDigest.getInstance("SHA-1");
        md.update(Files.readAllBytes(path.toPath()));
        StringBuilder sb = new StringBuilder();
        byte[] digest = md.digest();
        for (byte b : digest)
        {
            int value = b & 0xFF;
            if (value < 16)
            {
                sb.append("0");
            }
            sb.append(Integer.toHexString(value).toUpperCase(Locale.ROOT));
        }
        return sb.toString();
    }
    
}