You can do something like what i did with my List< Future< String > > or any other Arraylist, Type returned from other class called PingScan that returns List> because it implements service executor. Anyway the code down note that you can use foreach and retrieve data from the List.
PingScan p = new PingScan();
List<Future<String>> scanResult = p.checkThisIP(jFormattedTextField1.getText(), jFormattedTextField2.getText());
for (final Future<String> f : scanResult) {
try {
if (f.get() instanceof String) {
String ip = f.get();
Object[] data = {ip};
tableModel.addRow(data);
}
} catch (InterruptedException | ExecutionException ex) {
Logger.getLogger(gui.class.getName()).log(Level.SEVERE, null, ex);
}
}