Create Account and SignIn using Firebase Authentication

Android Firebase Auth

    private void createAccount(final String email, final String password) {

        mAuth.createUserWithEmailAndPassword(email, password)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()) {
                            Intent i = new Intent(LoginActivity.this, MainActivity.class);
                            startActivity(i);
                        } else {
                            Toast.makeText(LoginActivity.this, "Authentication failed.",
                                    Toast.LENGTH_SHORT).show();
                        }
                    }
                });
    }

    private void signIn(String email, String password) {

        mAuth.signInWithEmailAndPassword(email, password)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()) {
                            Intent i = new Intent(LoginActivity.this, MainActivity.class);
                            startActivity(i);
                        } else {
                            Toast.makeText(LoginActivity.this, "Authentication Failed",
                                    Toast.LENGTH_SHORT).show();
                        }
                    }
                });

    }