Serialization

package streams2;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class app {
    public static void main(String[] args) throws IOException {
        //macierz();
        //echo();
        bitFileCopy("t.png", "t2.png");
    }

    private static void echo() throws IOException
    {
        TextRew t = new TextRew();
        while(!t.stop())
        {
            t.readLine();
            t.printR();
        }
    }

    private static void macierz() throws IOException
    {
        Macierz m = new Macierz();
        m.printToFile();
        m.printAv();
        m.readFromFile();
        m.printAv();
        m.serializeToFile();
        m.deserializeFromFile();
        //m.bitFileCopy("CloneFile.txt");
    }
        public static int bitFileCopy(String fName, String toFile) throws FileNotFoundException, IOException
    {
        File from = new File(fName);
        File target = new File(toFile);
        FileInputStream in = new FileInputStream (from);
        FileOutputStream out = new FileOutputStream (target);
        int counter = 0;
        int triger = 0;
        byte [] b = new byte [1024];
        do
        {
            triger = in.read(b);
            if (triger > 0)
            {
                counter += triger;
                out.write(b);
            }
        }
        while(triger != -1);
        in.close();
        out.close();
        return counter;
    }

}
package streams2;

import java.io.*;
import java.util.Random;
import java.util.Scanner;

public class Macierz implements Serializable
{
    protected double[][] mac;
    protected File sFile;
    public File bitFile;

    public Macierz()
    {
        sFile = new File("Macierz.txt");
        bitFile = new File("bitFile.txt");
        mac = new double[5][];
        for (int i = 0; i < 5; i++)
        {
            mac[i] = new double[5];
        }
        Random r = new Random();
        for (int i = 0; i < 5; i++)
        {
            for (int j = 0; j < 5; j++)
            {
                mac[i][j] = r.nextDouble()* 100;
            }
        }
    }

    public void printToFile() throws IOException
    {
        BufferedWriter w = new BufferedWriter(new FileWriter(sFile));
        w.write("Macierz");
        w.newLine();
        w.write("" + mac.length);
        w.newLine();
        w.write("" + mac[0].length);
        w.newLine();
        for (int i = 0; i < mac.length; i++)
        {
            for (int j = 0; j < mac[i].length; j++)
            {
                w.write(String.format("%.2f\t", mac[i][j]));
            }
            w.newLine();
        }
        //System.out.println(sFile.getCanonicalPath());
        w.close();
    }

    public void readFromFile() throws IOException
    {
        FileReader r = new FileReader(sFile);
        Scanner s = new Scanner(sFile);
        s.nextLine();
        int w = s.nextInt(), k = s.nextInt();
        mac = new double [w][];
        for (int i = 0; i < w; i++)
        {
            mac[i] = new double[k];
        }
        for(int i = 0; i < w; i++)
            for(int j = 0; j < k; j++)
            {
                mac[i][j] = s.nextDouble();
            }
    }

    public void printAv()
    {
        PrintWriter w = new PrintWriter(System.out, true);
        double a = 0;
        for(int i = 0; i < 5; i++)
        {
            for(int j = 0; j < 5; j++)
            {
                a += mac[i][j];
            }
        }
        w.println("" + a/25);
    }

    public void serializeToFile() throws IOException
    {
        FileOutputStream w = new FileOutputStream(bitFile);
        DataOutputStream out = new DataOutputStream(w);
        out.writeInt(mac.length);
        out.writeInt(mac[0].length);
        for(int i = 0; i < mac.length; i++)
            for(int j = 0; j < mac[i].length; j++)
                out.writeDouble(mac[i][j]);
        out.close();
        w.close();
    }

    public void deserializeFromFile() throws IOException
    {
        FileInputStream wej = new FileInputStream(bitFile);
        DataInputStream in = new DataInputStream(wej);
        int w = in.readInt();
        int k = in.readInt();
        mac = new double[w][];
        for(int i = 0; i < w; i++)
        {
            mac[i] = new double[k];
            for(int j = 0; j < k; j++)
                mac[i][j] = in.readDouble();
        }
        in.close();
        wej.close();
    }

}