MyClass NotSerializableException

Question

I created a class named Components. It has some components like Button, TextArea, VerticalLayout, etc. I didn't make this class serializable because I don't need to, but when I start the server (I use Tomcat), I get this error:

java.io.NotSerializableException: com.vaadin13.Components
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1184)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1378)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1174)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1378)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1174)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at java.util.ArrayList.writeObject(ArrayList.java:766)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
...

Why does this error appear when my class isn't Serializable, and how do I fix it?

'I didn't make this class serializable because I don't need to': well. yes you *do* need to, and here is the proof. It happens *because* your class isn't `Serializable`, and the way to fix it is to *make* it implement `Serializable`. Surely this is obvious? — user207421, Mar 12 '19 at 04:24
https://stackoverflow.com/questions/13895867/java-io-notserializableexception — xingbin, Mar 12 '19 at 04:25
In Vaadin 8 i didn't get this error. It begins in Vaadin 10. — Champ, Mar 12 '19 at 07:32
So soemthing changed. So make it `Serializable`. What's the mystery? — user207421, Mar 12 '19 at 07:50

score 1 · Accepted Answer · edited Mar 12 '19 at 04:32

1

To fix this error implement the Serializable interface and give it an id.

 Public class Foo implements Serializable {
     private static final long serialversionUID = 1L; // example
      //code then
 }

edited Mar 12 '19 at 04:32

user207421

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answered Mar 12 '19 at 04:26

midugh

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Can you tell me please why we need that variable serialversionUID? – Champ Mar 12 '19 at 14:11
You ll find the answer here : https://stackoverflow.com/questions/285793/what-is-a-serialversionuid-and-why-should-i-use-it – midugh Mar 12 '19 at 14:36

MyClass NotSerializableException

1 Answers1