Java Digest digest(Serializable object)

Description

digest

License

Open Source License

Declaration

public static String digest(Serializable object) throws IOException, NoSuchAlgorithmException 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class Main {
    public static String digest(Serializable object) throws IOException, NoSuchAlgorithmException {
        assert object != null;
        try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream()) {
            try (ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream)) {
                objectOutputStream.writeObject(object);
                return createChecksumHex(outputStream.toByteArray());
            }/*from w  ww  .  jav  a 2 s  .  c om*/
        }
    }

    public static String createChecksumHex(byte[] bytes) throws NoSuchAlgorithmException, IOException {
        return createChecksumHex(bytes, new byte[0]);
    }

    public static String createChecksumHex(byte[] bytes, byte[] additionalBytes)
            throws NoSuchAlgorithmException, IOException {
        byte[] b = createChecksum(bytes, additionalBytes);
        String result = "";
        for (int i = 0; i < b.length; i++) {
            result += Integer.toString((b[i] & 0xff) + 0x100, 16).substring(1);
        }
        return result;
    }

    public static byte[] createChecksum(byte[] bytes, byte[] additionalBytes)
            throws IOException, NoSuchAlgorithmException {
        assert bytes != null;
        try (InputStream fis = new ByteArrayInputStream(bytes)) {
            byte[] buffer = new byte[1024];
            MessageDigest md = MessageDigest.getInstance("MD5");
            int bytesRead;
            do {
                bytesRead = fis.read(buffer);
                if (bytesRead > 0) {
                    md.update(buffer, 0, bytesRead);
                }
            } while (bytesRead != -1);
            if (additionalBytes != null && additionalBytes.length != 0) {
                md.update(additionalBytes);
            }
            return md.digest();
        }
    }
}

Related

1. digest(final String password)
2. digest(InputStream input, String algorithm)
3. digest(InputStream is, String digestAlgorithm)
4. digest(MessageDigest digest, InputStream data)
5. digest(MessageDigest method, File f)
6. digest(String alg, byte[] plainByte)
7. digest(String algorithm, byte[] bytes)
8. digest(String algorithm, byte[] data)
9. digest(String algorithm, String data)