Java

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package zadania1;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;

public class Zadania1
{
    public static void main(String[] args)
    {
        Zadania1 zad = new Zadania1();
        zad.NacitajObsahZoSubora("C:\\Users\\Ivan\\Desktop\\test.txt");
        zad.ZapisObsahDoSubora("C:\\Users\\Ivan\\Desktop\\test.txt", "Fuck this shit I am out");
    }

    public void NacitajObsahZoSubora(String fileName)
    {
        String text = "", tmp;
        try
        {
            FileInputStream file = new FileInputStream(fileName);
            InputStreamReader input = new InputStreamReader(file);
            try (BufferedReader fromFile = new BufferedReader(input))
            {
                while((tmp = fromFile.readLine()) != null)
                {
                    text = text+ "\n" + tmp;
                }
                System.out.println("Obsah suboru:\n" + text);
            }
        }
        catch(IOException e)
        {
        }
    }

    public void ZapisObsahDoSubora(String fileName, String writeText)
    {
        try
        {
            FileOutputStream file = new FileOutputStream(fileName);
            OutputStreamWriter output = new OutputStreamWriter(file);
            try (PrintWriter toFile = new PrintWriter(output))
            {
                toFile.println("" + writeText);
            }
        }
        catch (IOException e)
        {
        }
    }
}