package Files;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

// examples of saving and reading objects from files
public class SerializeFileExample {

    // read a serialized Bunny from an existing file
    public static Bunny readBunny() {
        Bunny bun = null;
        // files are teh dangers
        try {
            // stream that reads objects, buffered stream, file input stream
            ObjectInputStream stream
                    = new ObjectInputStream(
                            new BufferedInputStream(
                                    new FileInputStream(new File("bunny.txt"))));
            // temp to read into
            Object temp = "";
            // what if the contents of the file are bad
            try {
                // get the current object from the file 
                temp = stream.readObject();

                // check that it was a valid Bunny
                if (temp != null && temp instanceof Bunny) {
                    // if so, safe to cast
                    bun = (Bunny) temp;
                }
                // ClassNotFound means there was an object but our project
                // doesn't have the code for that class
            } catch (ClassNotFoundException ex) {
                System.out.println("Bad File contents");
            }

            // done with the file
            stream.close();
        } catch (IOException ex) {
            System.out.println("could not access file");
        }
        
        return bun;
    }

    // serialize a Bunny to a file
    public static void writeBunny() {
        // make bunny  
        Bunny bun = new Bunny("Clyde", 4);

        try {
            // make a stream that can write serialized objects to file
            ObjectOutputStream stream
                    = new ObjectOutputStream(
                            new BufferedOutputStream(
                                    new FileOutputStream(new File("bunny.txt"))));

                // put the bunny into the file
                stream.writeObject(bun);
                // since happy is transient, it will not be saved as part of the bunny
            
            // close the file
            stream.close();
        } catch (IOException ex) {
            System.out.println("could not access file");

        }
    }

    public static void main(String[] args) {
        writeBunny();
        readBunny();
    }
}