Nonserializable Exception in java

[deepali]

I'm getting NonserializableException when I'm converting an object to bytestream. At the following point my code is failing.
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos=null;
oos = new ObjectOutputStream(bos);
//oos.flush();
oos.writeObject(o1);
//Here at the time of calling writeObject() it's giving me the error
Please suggest any solution . Thanks in advance.

[JosAH]

Your object o1 or one of its members doesn't implement the Serializable interface.

kind regards,

Jos