ListIteratorE

ListIteratorE is a hypothetical exception type used in programming library designs to signal error conditions encountered by a list iterator during iteration. The name suggests an error related to the behavior or state of a ListIterator, and the E suffix follows a common convention for naming exception classes.

Purpose and scope

ListIteratorE is intended to encapsulate problems that arise while iterating over a list, such as illegal state transitions, boundary violations, or unsafe mutations of the underlying collection during iteration. It is not tied to a single language or standard library, but is often introduced in tutorials or design discussions to illustrate how an iterator can report errors to callers.

Typical scenarios

Common scenarios that might raise ListIteratorE include attempting to move past the end or before the beginning of a list, calling remove() or modify() without a preceding valid next()/previous() call, or detecting concurrent modifications to the list while iteration proceeds. In some design notes, ListIteratorE may be used to distinguish iteration-specific errors from general I/O or data access exceptions.

Design considerations

In practice, ListIteratorE would likely extend a runtime exception and may either represent a single error type or provide specialized subclasses for distinct conditions (for example, IllegalState, OutOfBounds, or ConcurrentMutation). Descriptive messages and, optionally, error codes, are common to aid debugging. Some libraries prefer reusing existing exceptions (such as IllegalStateException or NoSuchElementException) rather than adding a dedicated type.

See also

ListIterator, Iterator, IllegalStateException, NoSuchElementException, ConcurrentModificationException.