Object to String.

[Gelembjuk]

Hello.
I want somehow to save object to string and later restore it.

I have class MyClass. I want to create object, work with it and then save object properties to string. Later to start program and init object from that string.
I see that there is toString() method. But i am not sure it do that i need.

The class i code will be extended and i don't know now what properties will final class have.

How to save the object to string?

[Eranga]

Did you read that what toString() method is doing?

Can you show what you have done so far.

[sproket]

You can use the built-in java serialization. Or serialize java objects to XML. Do a google search "Java Serialization" to find out more.

[Norm]

You want to save the contents of an instance of your class in a disk file so that you can later read that file and recreate the object.
One way is to use serialization, another is to convert all the class's variables contents to a String and then write it a file. To get the object back, have a constructor in that class that will take the String that was written to the file and create an instance of the class.

[Gelembjuk]

Thanks.
Yes. I think something like serialization.
I have found some examples but there object is saved to file. I don't want to save object to file. I want to save it to string.
Can you write example where object it serialised and saved to string variable not in file?

[DarrylBurke]

Hmm. And then how do you save the String?

db

[Gelembjuk]

I have found the way to do this.
That is not readable string. But i must convert that bytes to string becouse it is the only way to transfer the object to externall app and the get it back.

String sobj="";
          MyClass a=new MyClass();
          a.setData("text");        
        try{
        ByteArrayOutputStream fos = new ByteArrayOutputStream();
        ObjectOutputStream outStream = new ObjectOutputStream( fos );
        outStream.writeObject( a );
        outStream.flush();
        sobj=fos.toString();

and sobj contains data that then can be read back to object

MyClass b=new MyClass();
      
        ByteArrayInputStream input = new ByteArrayInputStream(sobj.getBytes());
        ObjectInput oi = new ObjectInputStream(input);
        b = (MyClass)oi.readObject();
        oi.close();

This works as i expected.