// serialization/Worm.java
// (c)2017 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
// Demonstrates object serialization
import java.io.*;
import java.util.*;

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

public class Worm implements Serializable {
 private static Random rand = new Random(47);
 private Data[] d = {
 new Data(rand.nextInt(10)),
 new Data(rand.nextInt(10)),
 new Data(rand.nextInt(10))
 };
 private Worm next;
 private char c;
 // Value of i == number of segments
 public Worm(int i, char x) {
 System.out.println("Worm constructor: " + i);
 c = x;
 if(--i > 0)
 next = new Worm(i, (char)(x + 1));
 }
 public Worm() {
 System.out.println("No-arg constructor");
 }
 @Override
 public String toString() {
 StringBuilder result = new StringBuilder(":");
 result.append(c);
 result.append("(");
 for(Data dat : d)
 result.append(dat);
 result.append(")");
 if(next != null)
 result.append(next);
 return result.toString();
 }
 public static void
 main(String[] args) throws ClassNotFoundException,
 IOException {
 Worm w = new Worm(6, 'a');
 System.out.println("w = " + w);
 try(
 ObjectOutputStream out = new ObjectOutputStream(
 new FileOutputStream("worm.dat"))
 ) {
 out.writeObject("Worm storage\n");
 out.writeObject(w);
 }
 try(
 ObjectInputStream in = new ObjectInputStream(
 new FileInputStream("worm.dat"))
 ) {
 String s = (String)in.readObject();
 Worm w2 = (Worm)in.readObject();
 System.out.println(s + "w2 = " + w2);
 }
 try(
 ByteArrayOutputStream bout =
 new ByteArrayOutputStream();
 ObjectOutputStream out2 =
 new ObjectOutputStream(bout)
 ) {
 out2.writeObject("Worm storage\n");
 out2.writeObject(w);
 out2.flush();
 try(
 ObjectInputStream in2 = new ObjectInputStream(
 new ByteArrayInputStream(
 bout.toByteArray()))
 ) {
 String s = (String)in2.readObject();
 Worm w3 = (Worm)in2.readObject();
 System.out.println(s + "w3 = " + w3);
 }
 }
 }
}
/* Output:
Worm constructor: 6
Worm constructor: 5
Worm constructor: 4
Worm constructor: 3
Worm constructor: 2
Worm constructor: 1
w = :a(853):b(119):c(802):d(788):e(199):f(881)
Worm storage
w2 = :a(853):b(119):c(802):d(788):e(199):f(881)
Worm storage
w3 = :a(853):b(119):c(802):d(788):e(199):f(881)
*/