OnJava8-Examples/io/Worm.java
2015-04-20 15:36:01 -07:00

82 lines
2.3 KiB
Java

//: io/Worm.java
// Demonstrates object serialization.
import java.io.*;
import java.util.*;
import static net.mindview.util.Print.*;
class Data implements Serializable {
private int n;
public Data(int n) { this.n = n; }
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) {
print("Worm constructor: " + i);
c = x;
if(--i > 0)
next = new Worm(i, (char)(x + 1));
}
public Worm() {
print("Default constructor");
}
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');
print("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();
print(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();
print(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)
*///:~