orhanobut

final class DiskPersistence {
  
  private final static DiskPersistence instance = new DiskPersistence();
  
  public static DiskPersistence getInstance() {
    return instance;
  }
  
  private DiskPersistence() {
    // prevents to create a new instance

orhanobut

interface Persistence {
  void delete();
  void add(String value);
  String get();
}

static class EmptyPersistence implements Persistence {
  
  private static Persistence persistence;
  

orhanobut

interface Persistence {
  void delete();
  void add(String value);
  String get();
}

static class EmptyPersistence implements Persistence {
  @Override void delete(){
  }
  

orhanobut

interface Persistence {
  void delete();
  void add(String value);
  String get();
}

class FooBar {
  private Persistence persistence;
  
  void persistence(Persistence persistence) {

orhanobut

public class LoginFragment extends Fragment {
  void onLoginClicked(){}
  void makeLoginRequest(){}
  void displayHome(){}
  void onRegisterClicked(){}
  void displayRegistrationFragment(){}
}

orhanobut

public class Account {
  private final User user;
  private final String id;
  
  public Account(AccountResponse response) {
    id = response.id;
    user = User.newUser(response.userResponse);
  }
}

orhanobut

public class User {
  private final String id;
  private final String name;
  
  public User(UserResponse response) {
    if (response != null) {
      id = response.id;
      name = response.name;
    }
  }

orhanobut

public class Account {
  private final User user;
  private final String id;
  
  public Account(AccountResponse response) {
    id = response.id;
    UserResponse userResponse = response.userResponse;
    if (userResponse != null) {
      user = new User(response.userResponse);
    }

orhanobut

public class Account {
  private final User user;
  private final String id;
  
  public Account(AccountResponse response) {
    id = response.id;
    user = new User(response.userResponse);
  }
}

orhanobut

public class MyFragment extends Fragment {
  private static final String KEY_NAME = "KEY_NAME";
  
  public static Fragment newFragment(String name) {
    Fragment fragment = new MyFragment();
    Bundle bundle = new Bundle();
    bundle.putExtra(KEY_NAME, name);
    fragment.setArguments(bundle);
    return fragment;
  }