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convertion of data/objects into bytes so that they can be sent accross http network is serialization

Converting Objects into the tangible(Persistable) form(for ex. strings) is serialization. The purpose is to send object data across the network. The reverse process i.e again converting the same string into the object is deserialization

serialization is the process of converting an object into a sequence of bits so that it can be stored on a storage medium (such as a file, or a memory buffer) or transmitted across a network connection link. When the resulting series of bits is reread according to the serialization format, it can be used to create a semantically identical clone of the original object. For many complex objects, such as those that make extensive use of references this process is not straightforward.

Serialization is a mechanism by which you can save the state of an object by converting it to a byte stream.
Two types:
1.Binary Serializable
2.XML Serializable
Methods:
The serializable interface is an empty interface, it does not contain any methods. So we do not implement any methods.
Use:
Whenever an object is to be sent over the network, objects need to be serialized. Moreover if the state of an object is to be saved, objects need to be serilazed.
Externalizable:
Externalizable is an interface which contains two methods readExternal and writeExternal. These methods give you a control over the serialization mechanism. Thus if your class implements this interface, you can customize the serialization process by implementing these methods.

Regards,
Nithya.R
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