Reading an Object From a File : Object Serialization « File « Java Tutorial





import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

public class MainClass {
  public static void main(String[] args) throws Exception {
    Junk obj1 = new Junk("A");
    Junk obj2 = new Junk("B");
    Junk obj3 = new Junk("V");
    ObjectOutputStream objectOut = new ObjectOutputStream(new BufferedOutputStream(
        new FileOutputStream("C:/JunkObjects.bin")));

    objectOut.writeObject(obj1); // Write object
    objectOut.writeObject(obj2); // Write object
    objectOut.writeObject(obj3); // Write object
    objectOut.close(); // Close the output stream

    ObjectInputStream objectIn = null;
    int objectCount = 0;
    Junk object = null;

    objectIn = new ObjectInputStream(new BufferedInputStream(new FileInputStream(
        "C:/JunkObjects.bin")));

    // Read from the stream until we hit the end
    while (objectCount < 3) {
      object = (Junk) objectIn.readObject();
      objectCount++;
      System.out.println(object);
    }

    objectIn.close();

  }
}

class Junk implements Serializable {
  String str;

  public Junk(String s) {
    str = s;
  }

}










11.38.Object Serialization
11.38.1.Conditions for Serialization
11.38.2.Storing Objects in a File
11.38.3.Reading an Object From a File
11.38.4.Serializing Variations on an Object
11.38.5.Writing objects sequentially to a file with class ObjectOutputStream
11.38.6.Read a file of objects sequentially and displays each record
11.38.7.Only parent class is Serializable
11.38.8.Saving and restoring the state of classes
11.38.9.Class combination Serialization
11.38.10.Controlling serialization by adding your own
11.38.11.Serialization with ObjectInputStream and ObjectOutputStream
11.38.12.Deal with transient in Object Serialization
11.38.13.Serialization Utilities