show a fragment

MainActivity.java

    private void showFragmentRoutine(Class<?> fragment, String tag) {
        try {
            FragmentManager fm = getFragmentManager();
            if (fm.findFragmentByTag(tag) != null) {
                fm.popBackStack(tag, 0);
            } else {
                fm.beginTransaction()
                    .replace(R.id.container, (Fragment) Class.forName(fragment.getName()).newInstance(), tag)
                    .addToBackStack(tag)
                    .commit();
            }
        } catch (ClassNotFoundException e) {
            tabSpawnExceptionHandler(e);
        } catch (IllegalAccessException e) {
            tabSpawnExceptionHandler(e);
        } catch (InstantiationException e) {
            tabSpawnExceptionHandler(e);
        }
    }

    private void tabSpawnExceptionHandler(Exception e) {
        e.printStackTrace();
        Toast.makeText(this, "Något gick fel när en flik skulle visas", Toast.LENGTH_SHORT).show();
    }