Java tutorial
import java.io.ByteArrayOutputStream; import java.io.DataOutputStream; import java.math.BigInteger; import java.security.MessageDigest; public class Main { public static void main(String[] args) throws Exception { ByteArrayOutputStream baos = new ByteArrayOutputStream(); DataOutputStream dos = new DataOutputStream(baos); MessageDigest md = MessageDigest.getInstance("MD5"); SomeObject testObject = new SomeObject(); dos.writeInt(testObject.count); dos.writeLong(testObject.product); dos.writeDouble(testObject.stdDev); dos.writeUTF(testObject.name); dos.writeChar(testObject.delimiter); dos.flush(); byte[] hashBytes = md.digest(baos.toByteArray()); BigInteger testObjectHash = new BigInteger(hashBytes); System.out.println("Hash " + testObjectHash); dos.close(); } } class SomeObject { int count = 200; long product = 1; double stdDev = 1.456d; String name = "Name"; char delimiter = '\n'; }