Hi,
I have a class that implements java.io.Serializable interface.So all the variables in that class is serilaizable. But i want to make some of the variables are should not serializable. Is it possible?
thanks, Ravi
views:
68answers:
2
+4
A:
Mark those variables as transient.
e.g.
class A implements Serializable{
int a;
transient int b;
}
When an object of A is serialized, the transient field b will not be serialized.
missingfaktor
2010-01-09 20:19:31
Thanks Grey..But any other way?
Ravi K Chowdary
2010-01-09 20:21:36
What's wrong with `transient`? How else would you want to do it?
skaffman
2010-01-09 20:22:54
You can write your own custom readObject and writeObject and serialize what you like how you like. But one keyword is simpler.
Peter Lawrey
2010-01-09 20:25:36
or maybe `java.io.Externalizable`?
missingfaktor
2010-01-09 20:27:23
@peter: Great job..Thanks a lot
Ravi K Chowdary
2010-01-09 20:28:37
Peter Lawrey: You should be always calling `defaultReadObject`, `defaultWriteObject`, `getFields` or `putFields` (might have got the names wrong - compiler will tell you) at the start of your `readObject`/`writeObject`. kalyaniRavi: There is another way involving a `static final` field name `serialPersistentFields` (something like that - if you misspell it, the compiler will not tell you!).
Tom Hawtin - tackline
2010-01-09 20:55:08
+1
A:
If you don't want to use transient (why not?), you can implement Externalizable and implement your own protocol:
public class Spaceship implements Externalizable {
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
// ...
}
public void writeExternal(ObjectOutput out) throws IOException {
// ...
}
}
If that's too extreme, maybe you just want to customize the serialization a bit? Keep implementing Serializable and implement your own writeObject and readObject methods.
Here's a bunch of examples: http://java.sun.com/developer/technicalArticles/Programming/serialization/
ZoogieZork
2010-01-09 20:30:59