String s="";
     String currentLine;
try{
    BufferedReader identifier = new BufferedReader (new FileReader("asd.txt"));
    for(;;){
     if((currentLine = identifier.readLine())==null)break;
     s=s+currentLine+"\n"; 
    }
    System.out.println(s);
    }catch (IOException e) {
       System.err.println("Error: " + e);
   }