serializable class

[anilellendula kumar]

Hi All,

Does any one help me on how to Define methods in Serializable interface and how can i use that methods in a class, plz explain me with one example of writing state of an object in the file.

[Stuart Gray]

Serializable is a 'tag' interface - it has no methods to implement. It is just used to indicate that a class can be serialized (in some cases you specifically DONT want them to be serializable, which is why classes are not serializable by default).

This short example writes out an instance of a Person object to a file on disk. It assumes you have a person class that implements Serializable:

Person p = new Person("John Jones", 67);
File file = new File("data.dat");
FileOutputStream fout = new FileOutputStream(file);
ObjectOutputStream oout = new ObjectOutputStream(fout);
oout.write(p);
oout.close();

And the code to read it back in again:

File file = new File("data.dat");
FileInputStream fin = new FileInputStream(file);
ObjectInputStream oin = new ObjectInputStream(fin);
Person p = (Person) oin.read();
oin.close();

Both of these examples could throw an IOException so should be enclosed in try-catch statements.