nullpointer exception when assigning values

[oll3i]

public void wczytajPlik(String sciezka) throws FileNotFoundException
    {
    wczytaneDane.setText("");
     BufferedReader br = new BufferedReader(new FileReader(sciezka));    
     String line = null;
     String[] rows_cols = null;
    try {
        line = br.readLine();
        rows_cols = line.split("\\s+");
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
 
     int rows=new Integer(rows_cols[0]);
     int cols=new Integer(rows_cols[1]);
     wczytaneDane.append("Liczba wierszy:"+rows+"\n");
     wczytaneDane.append("Liczba kolumn:"+cols+"\n");
     klasyfikatorBayesa = new KlasyfikatorBayesa(cols-1,rows);
     System.out.println("Kolumny i wiersze ustawione\n"+"line="+line);
 
     int lineNumber=0;
 
     String[] aktualnyWiersz=null;
     Integer valueRowColumn = null;
      try {
        while((line = br.readLine()) != null)   { 
            aktualnyWiersz = line.split("\\s+");
 
 
            for(int i=0;i<aktualnyWiersz.length-1;i++){
 
                ///int valueInt = new Integer(aktualnyWiersz[i]).intValue();
                try {
                    valueRowColumn = new Integer(aktualnyWiersz[i]);
                } catch (NumberFormatException ignored) {
 
 
                    klasyfikatorBayesa.dane_treningowe[lineNumber][i]=valueRowColumn;
                }
 
 
            }
            System.out.println(lineNumber+"line="+line);
             wczytaneDane.append(lineNumber+")"+line+"\n");
              lineNumber++;
          }
 
        System.out.println("Dane treningowe wczytane");    
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
 
    }
 
 

for(int i=0;i<liczbaCol umn;i++){
System.out.prin tln("dane_treni ngowe[aktualny_wiersz][i]"+dane_treningo we[aktualny_wiersz][i]);
wiersz_analizow any[i]=dane_treningow e[aktualny_wiersz][i];
}

when i do System.out.prin tln wiersz_analizow any[i] is null
klasyfikatorBay esa.dane_trenin gowe[lineNumber][i]=valueRowColumn ; assigns null ? when i convert it to integer valueRowColumn = new Integer(aktualn yWiersz[i]); it returns NumberFormatExc eption


thank YOU

[r035198x]

Here are some tips.
1.) Define variables closet to where you're using them.
2.) Ignoring exceptions is not the in-thing to do.
3.) NumberFormatExc eption is what it says. You are trying to convert an inconvertible value. Print it to console and see what it is.

[oll3i]

i need to convert aktualnyWiersz[i] to Integer so i can assign value
klasyfikatorBay esa.dane_trenin gowe[lineNumber][i]=valueRowColumn ;
which is public Integer[][] dane_treningowe ;

how do i conver String to Integer?

[oll3i]

Integer valueRowColumn = Integer.valueOf (aktualnyWiersz[i]); throws number format exception

[r035198x]

i need to convert aktualnyWiersz[i] to Integer so i can assign value
klasyfikatorBay esa.dane_trenin gowe[lineNumber][i]=valueRowColumn ;
which is public Integer[][] dane_treningowe ;

how do i conver String to Integer?

Use Integer.parseIn t but you'll get an exception if the value being passed is not an integer.