implements Serializable

Serializability of a class is enabled by the class implementing the java.io.Serializable interface. Classes that do not implement this interface will not have any of their state serialized or deserialized. All subtypes of a serializable class are themselves serializable. The serialization interface has no methods or fields and serves only to identify the semantics of being serializable.

http://java.sun.com/docs/books/tutorial/essential/io/objectstreams.html

cotton.ma at 2007-7-12 10:41:31 >

Quick demo of "implements Serializable" versus not:

import java.io.*;

class S implements Serializable {}

class NotS {}

public class SerializableTest {

public static void main(String[] args) {

test(new S());

test(new NotS());

}

static void test(Object o) {

try {

ByteArrayOutputStream baos = new ByteArrayOutputStream(); //just for a sink

ObjectOutputStream out = new ObjectOutputStream(baos);

out.writeObject(o);

} catch (IOException e) {

e.printStackTrace();

}

}

}

Hippolytea at 2007-7-12 10:41:31 >