//: io/MyWorld.java // ©2015 MindView LLC: see Copyright.txt import java.io.*; import java.util.*; import static com.mindviewinc.util.Print.*; class House implements Serializable {} class Animal implements Serializable { private String name; private House preferredHouse; Animal(String nm, House h) { name = nm; preferredHouse = h; } @Override public String toString() { return name + "[" + super.toString() + "], " + preferredHouse + "\n"; } } public class MyWorld { public static void main(String[] args) throws IOException, ClassNotFoundException { House house = new House(); List animals = new ArrayList<>(); animals.add(new Animal("Bosco the dog", house)); animals.add(new Animal("Ralph the hamster", house)); animals.add(new Animal("Molly the cat", house)); print("animals: " + animals); ByteArrayOutputStream buf1 = new ByteArrayOutputStream(); ObjectOutputStream o1 = new ObjectOutputStream(buf1); o1.writeObject(animals); o1.writeObject(animals); // Write a 2nd set // Write to a different stream: ByteArrayOutputStream buf2 = new ByteArrayOutputStream(); ObjectOutputStream o2 = new ObjectOutputStream(buf2); o2.writeObject(animals); // Now get them back: ObjectInputStream in1 = new ObjectInputStream( new ByteArrayInputStream(buf1.toByteArray())); ObjectInputStream in2 = new ObjectInputStream( new ByteArrayInputStream(buf2.toByteArray())); List animals1 = (List)in1.readObject(), animals2 = (List)in1.readObject(), animals3 = (List)in2.readObject(); print("animals1: " + animals1); print("animals2: " + animals2); print("animals3: " + animals3); } } /* Output: animals: [Bosco the dog[Animal@19e0bfd], House@139a55 , Ralph the hamster[Animal@1db9742], House@139a55 , Molly the cat[Animal@106d69c], House@139a55 ] animals1: [Bosco the dog[Animal@10bedb4], House@103dbd3 , Ralph the hamster[Animal@167cf4d], House@103dbd3 , Molly the cat[Animal@a987ac], House@103dbd3 ] animals2: [Bosco the dog[Animal@10bedb4], House@103dbd3 , Ralph the hamster[Animal@167cf4d], House@103dbd3 , Molly the cat[Animal@a987ac], House@103dbd3 ] animals3: [Bosco the dog[Animal@a3a380], House@1453f44 , Ralph the hamster[Animal@ad8086], House@1453f44 , Molly the cat[Animal@be858], House@1453f44 ] *///:~