Removing the serialVersionUID warning in Eclipse

Looks familiar?

By default Eclipse warns you about not declaring a serialVersionUID for any serializable class you write. But what is the serialVersionUID and what’s the use of it?

http://www.javapractices.com/Topic45.cjp:

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.

http://java.sun.com/j2se/1.5.0/docs/api/java/io/Serializable.html:

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.

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.

A serializable class can declare its own serialVersionUID explicitly by declaring a field named “serialVersionUID” that must be static, final, and of type long:

ANY-ACCESS-MODIFIER static final long serialVersionUID = 42L;

If a serializable class does not explicitly declare a serialVersionUID, then the serialization runtime will calculate a default serialVersionUID value for that class based on various aspects of the class, as described in the Java(TM) Object Serialization Specification.

However, it is strongly recommended that all serializable classes explicitly declare serialVersionUID values, since the default serialVersionUID computation is highly sensitive to class details that may vary depending on compiler implementations, and can thus result in unexpected InvalidClassExceptions during deserialization.

Therefore, to guarantee a consistent serialVersionUID value across different java compiler implementations, a serializable class must declare an explicit serialVersionUID value. It is also strongly advised that explicit serialVersionUID declarations use the private modifier where possible, since such declarations apply only to the immediately declaring class — serialVersionUID fields are not useful as inherited members.

But how do you remove the Eclipse warning regarding the serialVersionUID not being declared for your serializable class?

Go to “Window” > “Preferences”. Type in the upper left search box “errors”. This should filter the options displayed. Browse the tree to “Java” > “Compiler” > “Errors Warnings”. Choose the “Potential programming problems” block and set the first option to “Ignore”. Hit the “Apply” button with sufficient thrust to cause it to succumb to you, the Eclipse master of them all n00bs.

Voila. You want a picture with that?