File to SHA1

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package test;

import java.io.FileInputStream;
import java.io.IOException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class FileToSHA1 {

    public static void main(String[] args) throws Exception {
        String str = ToSHA1("D:/Coding/HashCalc.exe");
        System.out.println(str);
    }

    private static String ToSHA1(String FilePath) throws Exception {
        MessageDigest md = MessageDigest.getInstance("SHA1");
        FileInputStream fis = new FileInputStream(FilePath);
        byte[] dataBytes = new byte[1024];
        int nread = 0;
        while ((nread = fis.read(dataBytes)) != -1) {
            md.update(dataBytes, 0, nread);
        };
        byte[] mdbytes = md.digest();
        //convert the byte to hex
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < mdbytes.length; i++) {
            sb.append(Integer.toString((mdbytes[i] & 0xff) + 0x100, 16).substring(1));
        }
        return sb.toString();
    }
}