Error recovery operators

Exceptions can occur in your Observable chain across many operators depending on what you are doing. We already know about the onError() event that is communicated down the Observable chain to the Observer. After that, the subscription terminates and no more emissions will occur. But sometimes, we want to intercept exceptions before they get to the Observer and attempt some form of recovery. We cannot necessarily pretend that the error never happened and expect emissions to resume, but we can attempt re-subscribing or switch to an alternate source Observable.

We can still do the former, just not with RxJava operators, which we will see shortly. If you find that the error recovery operators do not meet your needs, chances are you can compose them creatively.

 

For these examples, let's divide each integer emission by 10, where one of the emissions is 0. This will result in a "/ by zero" exception being emitted to the Observer, as shown in the following code snippet...