For Loop Iterator

Iterator and iterable objects in Java. Let's take a look at the difference between these two objects and how to implement the for each loop in a custom class.

Java Iterator is an interface that provides only the basic rules for iteration, and a foreach loop can be used for any container that implements the Iterable interface.

Java iterator is mainly used to manipulate collection objects in java. Java provides an iterator interface Iterator. Iterator can only move forward and cannot be rolled back.

Java Iterable interface and the Iterator interface. The class that implements the Iterable interface is iterable; the class that implements the Iterator interface is an iterator.

Often we want to delete some elements in the collection.　　Some might write that. public void operate (List list) {for (Iterator it = List.iterator (); It.hasnext ();)　　{String str = (string) it.next (); if (Str.equals ("Chengang")) {list ....

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