OBJECTINPUTSTREAM AND OBJECTOUTPUTSTREAM IN JAVA

These two classes are used to store object’s state permanently in files or send to remote computer via network.

ObjectInputStream – It is a subclass of ObjectInput interface. It implements the following method to read object from underline input stream – public Object readObject() throws IOException

ObjectOutputStream – It is a subclass of ObjectOutput interface. It implements the following method to write object to underline OutputStream – public void writeObject(Object ob) throws IOException

Note – To write or store object in external world it must be of type java.io.Serializable interface. It means this object’s class must be a subclass of java.io.Serializable interface, else writeObject() methods throws java.io.NotSerializableException

Note – Objects like DIS and DOS, OIS and OOS cannot be used to connect to source and destination directly. Hence, their constructors take other input and output stream class objects.