Posted in: Java Serialization
This is quite a common question basically interviewer is trying to know that whether you are familiar with usage of readObject (), writeObject (), readExternal () and writeExternal () or not. Java Serialization is done by java.io.ObjectOutputStream class. That class is a filter stream which is wrapped around a lower-level byte stream to handle the serialization mechanism. To store any object via serialization mechanism we call objectOutputStream.writeObject (saveThisobject) and to deserialize that object we call ObjectInputStream.readObject () method. Call to writeObject () method trigger serialization process in java. one important thing to note about readObject() method is that it is used to read bytes from the persistence and to create object from those bytes and its return an Object which needs to be casted on correct type.