import java.io.*;
import java.util.*;

class Data implements Serializable {
    private int n;
    public Data(int n) { this.n = n; }
    public String toString() { return Integer.toString(n); }
} // class Data

class Worm implements Serializable {
    private static Random rand = new Random();
    private Data[] d = {
        new Data(rand.nextInt(10)),
        new Data(rand.nextInt(10)),
        new Data(rand.nextInt(10))
    };
    private Worm next;
    private char c;
    public Worm(int nr_segments, char x) {
        System.out.println("Worm constructor: " + nr_segments);
        c = x;
        if (--nr_segments > 0)
            next = new Worm(nr_segments, (char)(x + 1));
    }
    public Worm() {
        System.out.println("Default constructor");
    }
    public String toString() {
        String s = ":" + c + "(";
        for (int i = 0; i < d.length; i++)
            s += d[i];
        s += ")";
        if (next != null)
            s += next;
        return s;
    }
} // class Worm

public class WormTest {
    public static void main(String[] args)
        throws ClassNotFoundException, IOException {
        Worm w = new Worm(6, 'a');
        System.out.println("w = " + w);
        ObjectOutputStream out =
            new ObjectOutputStream(new FileOutputStream("worm.out"));
        out.writeObject("Worm storage\n");
        out.writeObject(w);
        out.close(); // Also flushes output
        ObjectInputStream in =
            new ObjectInputStream(new FileInputStream("worm.out"));
        String s = (String)in.readObject();
        Worm w2 = (Worm)in.readObject();
        System.out.println(s + "w2 = " + w2);
        ByteArrayOutputStream bout =
            new ByteArrayOutputStream();
        ObjectOutputStream out2 = new ObjectOutputStream(bout);
        out2.writeObject("Worm storage\n");
        out2.writeObject(w);
        out2.flush();
        ObjectInputStream in2 =
            new ObjectInputStream(new ByteArrayInputStream(bout.toByteArray()));
        s = (String)in2.readObject();
        Worm w3 = (Worm)in2.readObject();
        System.out.println(s + "w3 = " + w3);
    }
} // class WormTest