Podstawy serializacji

Wprowadzenie

Interfejs Serializable

Kod: klasa Serializable

import java.io.Serializable;
public class Main {
  static class Person implements Serializable {
    String name;
    int age;
    Person(String n, int a) { name = n; age = a; }
    public String toString() { return name + "(" + age + ")"; }
  }
  public static void main(String[] args) {
    Person p = new Person("Ada", 30);
    System.out.println("Created: " + p);
  }
}

ObjectOutputStream

Kod: zapisywanie obiektu

import java.io.*;
public class Main {
  static class Person implements Serializable {
    String name; int age;
    Person(String n,int a){name=n;age=a;}
  }
  public static void main(String[] args) {
    Person p = new Person("Bob",25);
    try (ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream("person.ser"))) {
      out.writeObject(p);
      System.out.println("Object written");
    } catch(IOException e) {
      System.out.println("Error: " + e.getMessage());
    }
  }
}

Kod: odczytywanie obiektu

import java.io.*;
public class Main {
  static class Person implements Serializable {
    String name; int age;
    Person(String n,int a){name=n;age=a;}
    public String toString(){return name+"("+age+")";}
  }
  public static void main(String[] args) {
    try (ObjectInputStream in = new ObjectInputStream(new FileInputStream("person.ser"))) {
      Person p = (Person) in.readObject();
      System.out.println("Read: " + p);
    } catch(Exception e) {
      System.out.println("Error: " + e.getMessage());
    }
  }
}

Sprawdzenie serializacji

Podsumowanie