So I found the answer by myself, I'm writing the code here if someone else need it :
Let's say you have a contact object with a name and phonenumber (both strings) and you want to show them on a JTable retrieving the name and the number from backendless :
public void retrieveInformation(BackendlessDataQuery query,final DefaultTableModel model){
System.out.println("Retrieving Data...");
Backendless.Data.of(Contact.class).find(query, new AsyncCallback<BackendlessCollection<Contact>>() {
@Override
public void handleResponse(BackendlessCollection<Contact> backendlessCollection) {
Object[] row = new Object[2];
for (Contact map : backendlessCollection.getCurrentPage()){
row[0] = map.getName();
row[1] = map.getNumber();
model.addRow(row);
System.out.println("Retrieving Data complete !");
}
}
@Override
public void handleFault(BackendlessFault backendlessFault) {
System.out.println(backendlessFault.getMessage());
}
});}