Java J2ee Planet

Serialization is another important topic that needs to be well prepared whe n you are going fro interview. We have collected important topics that are asked by interview panel of one of the major companies. Just check them below How many methods in the Serializable interface? Which methods of Serializable interface should I implement? There is no method in the Serializable interface. It’s an empty interface which does not contain any methods. The Serializable interface acts as a marker, telling the object serialization tools that the class is serializable. So we do not implement any methods.  What is the difference between Serializalble and Externalizable interface? How can you control over the serialization process i.e. how can you customize the seralization process? When you use Serializable interface, your class is serialized automatically by default. But you can override writeObject() and readObject() two methods to control more complex object serailization process. When ...

Q1) What is Serialization? Ans) Serializable is a marker interface. When an object has to be transferred over a network ( typically through rmi or EJB) or persist the state of an object to a file, the object Class needs to implement Serializable interface. Implementing this interface will allow the object converted into bytestream and transfer over a network. Q2) What is use of serialVersionUID? Ans) During object serialization, the default Java serialization mechanism writes the metadata about the object, which includes the class name, field names and types, and superclass. This class definition is stored as a part of the serialized object. This stored metadata enables the deserialization process to reconstitute the objects and map the stream data into the class attributes with the appropriate type Everytime an object is serialized the java serialization mechanism automatically computes a hash value. ObjectStreamClass's computeSerialVersionU...