What is serialVersionUID exception class?
The serialization at runtime associates with each serializable class a version number called a serialVersionUID, which is used during deserialization to verify that the sender and receiver of a serialized object have loaded classes for that object that are compatible with respect to serialization.
What does serialVersionUID mean?
The SerialVersionUID can be used during deserialization to verify that the sender and receiver of a serialized object have loaded classes for that object that are compatible w.r.t serialization. If the deserialization object is different than serialization, then it can throw an InvalidClassException.
Is serialVersionUID still needed?
Simply put, we use the serialVersionUID attribute to remember versions of a Serializable class to verify that a loaded class and the serialized object are compatible. Therefore, it is not necessary for different classes to have unique values.
What is serialization exception?
SerializationException A generic exception indicating the problem in serialization or deserialization process. SerialFormat implementors should throw subclasses of this exception at any unexpected event, whether it is a malformed input or unsupported class layout.
Can two classes have same serialVersionUID?
Yes, you can. Serial versions of different classes are independent and do not interfere each other. Eclipse even proposes you to set serialVersionID by default value that is 1L . serialVersionUID is needed to remember versions of the class.
What is the use of serialVersionUID 1L?
The serialVersionUID is a universal version identifier for a Serializable class. Deserialization uses this number to ensure that a loaded class corresponds exactly to a serialized object. If no match is found, then an InvalidClassException is thrown.
How do you declare serialVersionUID?
A serializable class can declare its own serialVersionUID explicitly by declaring a field named serialVersionUID that must be static, final, and of type long.
Where do I find serialVersionUID?
File -> Settings -> Editor -> Inspections -> Java -> Serialization issues : Find serialization class without serialVersionUID and check it. Back to the editor, clicks on the class name, ALT + ENTER (Windows), it will prompts the Add serialVersionUID field option. A new serialVersionUID is auto-generated.
How serialVersionUID is generated when it’s not defined in code?
If class does not contain a serialVersionUID field, its serialVersionUID will be automatically generated by the compiler. Different compilers, or different versions of the same compiler, will generate potentially different values.
Can 2 classes have same serialVersionUID?
Yes, you can. Serial versions of different classes are independent and do not interfere each other. Eclipse even proposes you to set serialVersionID by default value that is 1L .
Why is exception serializable?
All exceptions by default are serializable and that’s a language design decision because the authors wanted exceptions to be capable of being sent across the wire without any special configuration.
What is a serialversionuid and why should I use it?
SerialVersionUID is a unique identifier for each class, JVM uses it to compare the versions of the class ensuring that the same class was used during Serialization is loaded during Deserialization. Specifying one gives more control, though JVM does generate one if you don’t specify.
What happens if you forget to update serialversionuid in Java?
If you do forget to update the field, you might end up with two different versions of a class with different structure but with the same serialVersionUID. If this happens, the default mechanism ( in.defaultReadObject ()) will not detect any difference, and try to de-serialize incompatible data.
When does deserialization result in an invalidclassexception?
If the receiver has loaded a class for the object that has a different serialVersionUID than that of the corresponding sender’s class, then deserialization will result in an InvalidClassException.
What does serialization runtime do in servlet AEM?
The serialization runtime associates with each serializable class a version number, called a serialVersionUID, which is used during deserialization to verify that the sender and receiver of a serialized object have loaded classes for that object that are compatible with respect to serialization.