After converting an object to a String, how can I get the object back from the string again?

Question

I was creating a simple android application in which I am converting an object to String. How can I re-convert the object from the string?

I am converting my object to String using the following line of code.

String convertedString = object.toString();

You need to implement your own method in the class of your object. — Stéphane Ammar, Nov 20 '17 at 08:21
You can hold the object with other variable before string converting method then you have object in seperate. — Mohamed Mohaideen AH, Nov 20 '17 at 08:24
Why would you want to convert an object to a string and back? Are you doing it to store the object in a file? What is the class of the object? — Андрей Беньковский, Nov 20 '17 at 14:44

score 0 · Answer 1 · answered Nov 20 '17 at 08:22

You can't**, because that is not what the toString method is for. It's used to make a readable representation of your Object, but it's not meant for saving and later reloading.

What you are looking for instead is Serialization. See this tutorial here to get started:

http://www.tutorialspoint.com/java/java_serialization.htm

** Technically you could, but you shouldn't.

score 0 · Answer 2 · answered Nov 20 '17 at 08:28

0

You can do it in two ways:

Java Serialization
Using Gson library (more simple), remember the the purpose of this lib is to convert simply json to object and viceversa when working with REST services.

Hope it helps

answered Nov 20 '17 at 08:28

appersiano

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score 0 · Answer 3 · answered Nov 20 '17 at 08:34

You can use Serialization to convert object to string and vise versa:

 String serializedObject = "";

 // serialize the object
 try {
     ByteArrayOutputStream bo = new ByteArrayOutputStream();
     ObjectOutputStream so = new ObjectOutputStream(bo);
     so.writeObject(myObject);
     so.flush();
     serializedObject = bo.toString();
 } catch (Exception e) {
     System.out.println(e);
 }

 // deserialize the object
 try {
     byte b[] = serializedObject.getBytes(); 
     ByteArrayInputStream bi = new ByteArrayInputStream(b);
     ObjectInputStream si = new ObjectInputStream(bi);
     MyObject obj = (MyObject) si.readObject();
 } catch (Exception e) {
     System.out.println(e);
 }

score 0 · Answer 4 · answered Nov 20 '17 at 08:38

Use Java Serialization for doing same.

Go with below link for better understand how to convert java object.
Ex. http://www.geeksforgeeks.org/serialization-in-java/

Also You can go with this link:

How to convert the following json string to java object?

After converting an object to a String, how can I get the object back from the string again?

4 Answers4