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Decided to attempt the main method.. pls help

Serializing/deserializing the Solution class doesn't work.
Fix the bugs without changing method or class signatures.
The main method is not tested.

Write the verification code yourself in the main method:
1) create an instance of the Solution class
2) write data to it (writeObject)
3) serialize the Solution class (writeObject(ObjectOutputStream out))
4) deserialize, get a new object
5) write data to the new object (writeObject)
6) verify that the file contains the data from Items 2 and 5

Requirements:

The stream field must be declared with the transient modifier.
The writeObject(ObjectOutputStream out) method should not call the close method on the stream passed as an argument.
The readObject(ObjectInputStream in) method should not call the close method on the stream passed as an argument.
In the readObject(ObjectInputStream in) method, the stream field must be initialized with a new FileOutputStream object using the arguments (fileName, true).
In the Solution class constructor, the stream field must be initialized with a new FileOutputStream object with the argument (fileName).

package com.codegym.task.task20.task2022; import java.io.*; /* Overriding serialization in a thread */ public class Solution implements Serializable, AutoCloseable { private transient FileOutputStream stream; public Solution(String fileName) throws FileNotFoundException { this.stream = new FileOutputStream(fileName); } public void writeObject(String string) throws IOException { stream.write(string.getBytes()); stream.write("\n".getBytes()); stream.flush(); } private void writeObject(ObjectOutputStream out) throws IOException { out.defaultWriteObject(); // out.close(); } private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { in.defaultReadObject(); // in.close(); String fileName = " "; this.stream = new FileOutputStream(fileName , true); } @Override public void close() throws Exception { System.out.println("Closing everything!"); stream.close(); } public static void main(String[] args) { Solution solution = new Solution("Foo.ser"); FileOutputStream fs = new FileOutputStream("Foo.ser"); ObjectOutputStream os = new ObjectOutputStream(fs); os.writeObject(solution); FileInputStream fis = new FileInputStream("Foo.ser"); ObjectInputStream ois = new ObjectInputStream(fis); Solution osRestore = (Solution) ois; } }

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Nouser

Level 36 , Germany

9 September 2020, 11:15

goal is, to create a Solution object and then call the writeObject method an that object without the need for creating stream objects in the main method (despite ObjectOutputStream, ObjectInputStream). You already have the path / fileName inside of the constructor. Then you see that fileName being used in readObject(). So why do you initialize a new variable with that name and set it to " " when the fileName sent to the constructor is what you probably need?