java md5sum file

gistfile1.txt

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

public class TestCheckSum {

    public static void main(String args[]) throws Exception {
        String datafile = "c:\\INSTLOG.TXT";
        MessageDigest md = MessageDigest.getInstance("SHA1");
        FileInputStream fis = new FileInputStream(datafile);
        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 format
        StringBuffer sb = new StringBuffer("");
        for (int i = 0; i < mdbytes.length; i++) {
            sb.append(Integer.toString((mdbytes[i] & 0xff) + 0x100, 16).substring(1));
        }
        System.out.println("Digest(in hex format):: " + sb.toString());
    }
}