schu-r Code

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package at.it_open.openbase.security;

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

/**
 *
 * @author roland
 */
public class FileHash {

    public static String getHash(String file) throws IOException {
        StringBuffer hexString = null;
        try {
            MessageDigest md = MessageDigest.getInstance("SHA-512");
            FileInputStream fis = new FileInputStream(file);

            byte[] dataBytes = new byte[1024];

            int nread = 0;
            while ((nread = fis.read(dataBytes)) != -1) {
                md.update(dataBytes, 0, nread);
            }
            fis.close();
            byte[] mdbytes = md.digest();

            hexString = new StringBuffer();
            for (int i = 0; i < mdbytes.length; i++) {
                hexString.append(Integer.toHexString((0xFF & mdbytes[i])));
            }

            return hexString.toString();

        } catch (NoSuchAlgorithmException e) {
        }
        return "";
    }
}