Launch Exception on the onCreate of an Activity

Question

I am working on the development and refactoring of some Activity's that has similar behaviors in our projects, so to avoid code repetitions, for common functionalities, I created some Activity's base, which are inherited by the other Activities’s.

My problem is this, as what I’m creating is class groundwork (library), that can be used by several others, I need to ensure that whoever uses it will use it in the right way. Therefore, I would like to verify non-conformities in the parameters of class base and launch a Exception in case of non-conformities, so that these errors are captured in the development and testing phase.

That does not seem possible, follow what I would like to do next:

@Override
protected void onCreate(Bundle savedInstanceState) {
    userHelper = new UserHelper(this);

    super.onCreate(savedInstanceState);
    setContentView(R.layout.container_for_fragment);

    if (savedInstanceState == null) {
        if (mFragment != null) {
            getFragmentManager().beginTransaction()
                    .add(R.id.container, mFragment).commit();
        }else{
            // essa linha não compila: "Unhandled exception type Exception"
            throw new Exception("mFragment, deve ser setado antes da chamada do onCreate() da class base \"ListAbstractActivity\"");
        }
    }
}

Doubts

1. Is there any way to do something about it?
2. What I’m trying to do is right?
3. Is there any plausible alternative to this situation?

Answer 1

In case of error "Unhandled Exception type Exception" that you mentioned, this code will not compile because Exception is a checked Exception, that is, the method by which the spear is obliged to declare that it can launch it:

onCreate(...) throws Exception {

Since the compiler will probably not let you declare it (as it would change the method signature onCreate), launch instead a RuntimeException or one of your subclasses that you consider most appropriate.