java.util · java.base · since Java 1.2

Iterator

declaration

public interface Iterator<E>

The cursor protocol behind every for-each: hasNext/next, plus remove() — the only legal way to delete during iteration of most collections.

Key methods

`boolean hasNext() / E next()`	The stepping pair; next() past the end throws NoSuchElementException.
`default void remove()`	Delete the last-returned element without ConcurrentModificationException — the only safe removal mid-iteration.
`default void forEachRemaining(Consumer<? super E>)`	Drain the rest of the iterator in one call.