warning: [serial] serializable class SomeClass has no definition of serialVersionUID

Question

Eventhough this class is not intended ot set to be serializable, I'm getting this unusual warning! Could someone let me know if you have come across such odd warning?!

C:\Documents and Settings\...filename.java:60: warning: [serial] serializable class SomeClass has no definition of serialVersionUID
public class NewPortalConnection extends javax.swing.JFrame {

Regards

score 54 · Accepted Answer · edited May 23 '17 at 12:25

54

This warning comes when you derive from a class that implements Serializable. In your case, the Serializable parent class is JFrame.

You can suppress this warning with @SuppressWarnings("serial"), or give the class a serialVersionUID: private static final long serialVersionUID = ...; (with a long value for the dots).

There is a discussion here on SO on which is preferable.

edited May 23 '17 at 12:25

Community

1
1

answered Oct 19 '11 at 15:09

S.L. Barth is on codidact.com

8,198
71
51
66

So what do you think I should to do to get rid of this warning??! – Sam Oct 19 '11 at 15:13
I have added your options to the answer. – S.L. Barth is on codidact.com Oct 19 '11 at 15:17
Thanks S.L. Barth for the accurate and spot on answer! You saved me a lot of hasstle! All the best! – Sam Oct 19 '11 at 15:33
Is there any recommended way to derive the unique value? – Kevin Cox Feb 16 '14 at 22:17
1

@KevinCox Not sure what is recommended, but the Eclipse IDE has an option "Add generated serial Version ID". – S.L. Barth is on codidact.com Feb 17 '14 at 06:37

VasiliNovikov · Answer 2 · 2019-03-01T12:17:36.070

7

If you know your application never serializes things, add -Xlint:-serial to command line arguments of javac. For example,

javac -Xlint -Xlint:-serial *****

This way you will have all warnings except "serial".

edited Mar 01 '19 at 12:17

answered Dec 15 '15 at 10:58

VasiliNovikov

9,681
4
44
62

Is there any way to except serial for one folder? – Don Jose Jun 11 '20 at 10:16
@doN I don't know (except multi-stage javac invocation for different folders). I'm not working with java normally anyway, only Scala or Rust, so I'm no expert in these things. – VasiliNovikov Jun 11 '20 at 12:04
Looks like i have to deepdive on the documentation:) – Don Jose Jun 12 '20 at 09:10

score 7 · Answer 3 · answered Oct 19 '11 at 15:12

7

JFrame implements Serializable, so all extending classes also implement Serializable.

Here's a tutorial about Serializable and serialVersionUID, but to really understand the topic you should read Chapter 11 of Effective Java (2nd Ed) by Joshua Bloch

answered Oct 19 '11 at 15:12

Sean Patrick Floyd

292,901
67
465
588

I will definitely read the suggested papers! Thank you Sean! – Sam Oct 19 '11 at 15:32

warning: [serial] serializable class SomeClass has no definition of serialVersionUID

3 Answers3

Linked