gistfile1.java

 loginButton.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) {
                    // First check if email or password are empty, if any of those
                    // is empty, focus them. Else try to authenticate on the
                    // endpoint.
                    final EditText email = (EditText) rootView.findViewById(R.id.login_email);
                    final EditText password = (EditText) rootView.findViewById(R.id.login_password);

                    AuthenticatorMock authenticator = new AuthenticatorMock();
                    try {
                        final User user = authenticator.login(email.getText().toString(),
                                password.getText().toString());
                    }   catch (InvalidCredentialsException e) {
                        AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());

                        builder.setTitle(R.string.credential_failure_title)
                               .setMessage(R.string.crentials_failure_message);

                        AlertDialog dialog = builder.create();
                    }
                }
            });

/// ===== 

public class AuthenticatorMock implements AuthenticatorInterface {

    public User login(String username, String password) throws InvalidCredentialsException {
        if (username.equals("Carmen") && password.equals("Sawada")) {
            return new User("chiina@gmail.com");
        } else {
            // TODO: User values/strings.xml
            throw new InvalidCredentialsException("Credenciales Equivocados");
        }
    }
}

Execution failed for task ':app:compileDebugJava'.

Compilation failed; see the compiler error output for details.
/home/puercopop/Projects/NoQ/app/src/main/java/com/puercopop/noq/LoginActivity.java
Error(87, 25) error: exception InvalidCredentialsException is never thrown in body of corresponding try statement