What Is Fail Fast and Fail Safe Iterator in Java

The Java Collection supports two types of iterators; Fail Fast and Fail Safe. These iterators are very useful in exception handling. The Fail fast iterator aborts the operation as soon it exposes failures and stops the entire operation. Comparatively, Fail Safe iterator doesn’t abort the operation in case of a failure.

What are Fail fast and fail safe iterator?

The Java Collection supports two types of iterators; Fail Fast and Fail Safe. These iterators are very useful in exception handling. The Fail fast iterator aborts the operation as soon it exposes failures and stops the entire operation. Comparatively, Fail Safe iterator doesn’t abort the operation in case of a failure.

What is Fail fast approach in Java?

When a problem occurs, a fail-fast system fails immediately. In Java, we can find this behavior with iterators. Incase, you have called iterator on a collection object, and another thread tries to modify the collection object, then concurrent modification exception will be thrown. This is called fail-fast.