Java 8. Casting Object[] to String[][]

Question

I\'m trying to load data from file into JTable. So, using Java 8 streams it is very easy to load file into array of strings:

BufferedReader br = new Buffered         


        

Answer 1

Splitting that piece of casting out into a loop should do it.

BufferedReader br = new BufferedReader(new FileReader(f));
Object[] data = br.lines().map((s)->{
        String[] res = {s,"1"}; // Here's some conversion of line into String[] - elements of one row
        return res;
    }).toArray();

String[][] dataMatrix = new String[data.length][];
for(int i = 0; i < data.length; i++){
    dataMatrix[i] = (String[]) data[i];
}
TableModel m = new DefaultTableModel(dataMatrix, cols);

Answer 2

If you use toArray(String[][]::new) instead of toArray() it will return a String[][] instead of an Object[] and you wont need to cast it at all (if you assign it to a String[][]).