import java.io.FileWriter;
import java.io.IOException;

class FileHandler {
    public void writeFile() {
        try {
            tryWriteFile();
        } catch (IOException e) {
            System.err.println("Hiba! A fájlbaírás sikertelen!");
            System.err.println(e.getMessage());
        }
    }
    public void tryWriteFile() throws IOException {
        FileWriter fw = new FileWriter("adat.txt", true);
        fw.write("bármi\n");	
        fw.close();        
    }
}

class App { 
    public static void main(String args[]) throws Exception {
        new FileHandler().writeFile();
    }
}