SerialVersionUID

 The serialization process at runtime associates an id with each Serializable class which is known as SerialVersionUID. It is used to verify the sender and receiver of the serialized object. The sender and receiver must be the same. To verify it, SerialVersionUID is used. The sender and receiver must have the same SerialVersionUID, otherwise, InvalidClassException will be thrown when you deserialize the object. We can also declare our own SerialVersionUID in the Serializable class. To do so, you need to create a field SerialVersionUID and assign a value to it. It must be of the long type with static and final. It is suggested to explicitly declare the serialVersionUID field in the class and have it private also. For example:

  1. private static final long serialVersionUID=1L;  
import java.io.Serializable;    
class Employee implements Serializable{    
 private static final long serialVersionUID=1L;    
 int id;    
 String name;    
 public Student(int id, String name) {    
  this.id = id;    
  this.name = name;    
 }    
} 


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