Meaning of @Nullable java (android)

Question

I saw this video on how to create fragments in Android and I'm unable to understand the meaning of @Nullable here. Also in the video (thenewboston) @Nullable was used on parameter:

@Override
public View onCreateView(LayoutInflater inflater,@Nullable ViewGroup container,@Nullable Bundle savedInstanceState)
 {
return super.onCreateView(inflater, container, savedInstanceState);
    }

But later on when I tried to create the same override method Android Studio generated this:

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

}

Can someone please explain me the use of @Nullable here?

Answer 1

It means that the return value of onCreateView method can be null.

From the Android documentation:

Denotes that a parameter, field or method return value can be null.

When decorating a method call parameter, this denotes that the parameter can legitimately be null and the method will gracefully deal with it. Typically used on optional parameters.

When decorating a method, this denotes the method might legitimately return null.

This is a marker annotation and it has no specific attributes.

You can find more details and examples in this Android Support Annotation page