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Java Java Data Structures Organizing Data Serialization

Matthew Francis
Matthew Francis
6,967 Points
Posted by Matthew Francis
Matthew Francis
6,967 Points

What does writeObject() and readObject() does?

I tried reading the documentation/re-listen to what Craig' said, but can't seem to fully comprehend what the they do.

This is my undertanding, not sure if it is right. Code:

public class Treets{
  public static void save(Treet[] treets){
    try(
        FileOutputStream fos = new FileOutputStream("trees.ser");//sequence of bytes --> file
        ObjectOutputStream oos =  new ObjectOutputStream(fos);//object --> sequence of bytes
    )
    {
      oos.writeObject(treets);//means: what object to convert to sequence of bytes?

    public static Treet[] load(){
      Treet[] treets = new Treet[0];
      try(
        FileInputStream fis = new FileInputStream("treets.ser");//sequence of bytes <-- file
        ObjectInputStream ois = new ObjectInputStream(fis);) //sequence of bytes --> object.
      {
        treets = (Treet[]) ois.readObject(); //means: what file to convert to an object
      return treets;
    }
  }
}

1 Answer

Sabina Belyaeva
Sabina Belyaeva
7,310 Points
Sabina Belyaeva
Sabina Belyaeva
7,310 Points

Hello, Matthew, I have struggled on with the same problem. And I think I have found an answer:

public class Treets{

  public static void save(Treet[] treets){

    try(
        FileOutputStream fos = new FileOutputStream("trees.ser");// RECEIVE sequence of bytes --> file
        ObjectOutputStream oos =  new ObjectOutputStream(fos);//CREATE AN object --> sequence of bytes( Like  a box 
for our future date) 
    )

    }
      oos.writeObject(treets);//means: Treets - is our date and we put it in our box. (We write specific information in our object)




public static Treet[] load(){
      Treet[] treets = new Treet[0];
      try(
        FileInputStream fis = new FileInputStream("treets.ser");//sequence of bytes <-- file
        ObjectInputStream ois = new ObjectInputStream(fis);) //sequence of bytes --> object.
      {
        treets = (Treet[]) ois.readObject(); //We again receive bytes from array of treets (It is a process of reconstruction of our data)
      return treets;
    }
}
}

I hope it will be helpful :)