staticfactor3.java

public class Constants {
  public static final String KEY_USER = "KEY_USER";
}

// sends the data
public class LoginActivity extends Activity {
  void displayHome() {
    Intent intent = new Intent(this, HomeActivity.class);
    intent.putExtra(Constants.KEY_USER, user);
    startActivity(intent);
  }
}

// gets the data
public class HomeActivity extends Activity {
  @Override public void onCreate(Bundle bundle) {
    String user = getIntent.getStringExtra(Constants.KEY_USER);
  }
}