it.add("four");//[one, two, three, four, five]//it.set("3");//[one, two, 3, five]//对比输出结果} } System.out.println(list); } } 2、增强for循环: (1)for(元素的数据类型 变量:Collection集合or数组){ }; packagecom.oracle.demo01;importjava.util.ArrayList;importjava.util.Collect...
Java中的Iterator是一种fail-fast的设计。 当Iterator迭代一个容器的时候,如果此时有别的方法在更改Collection(容器)的内容,那么Iterator就会抛出 ConcurrentModificationException 。正如官方文档中反复强调的: Thus, in the face of concurrent modification, the iterator fails quickly and cleanly, rather than risking ...
ThreadOne 遍历:0ThreadTwo run:0ThreadTwo run:1ThreadTwo run:2ThreadTwo run:3ThreadTwo run:4ThreadTwo run:5Exceptioninthread"Thread-0"java.util.ConcurrentModificationException at java
Exception in thread"main"java.util.ConcurrentModificationExceptionatjava.util.ArrayList$Itr.checkForComodification(ArrayList.java:911)atjava.util.ArrayList$Itr.next(ArrayList.java:861)atmoudle2.Test15.main(Test15.java:17)Process finished with exit code1 因为此时集合本身被破坏了,迭代出现错误。 为什么一...
import java.util.*; public class IteratorExampleDemo{ public static void main(String[] args) { //Step 1: create an hashSet Set<String> hashSet = new HashSet<String>(); //Step 2: Add elements in hash Set hashSet.add("I");
3.4.set() The last method worth mentioning isset(),which lets us replace the element that was returned in the call tonext()orprevious(): String next = listIterator.next(); if( "ONE".equals(next)) { listIterator.set("SWAPPED"); } ...
In this tutorial, we will learn about the Java Iterator interface with the help of an example. All the Java collections include an iterator() method. This method returns an instance of iterator used to iterate over elements of collections.
An iterator over a collection.Iteratortakes the place ofEnumerationin the Java Collections Framework. Iterators differ from enumerations in two ways: Iterators allow the caller to remove elements from the underlying collection during the iteration with well-defined semantics. ...
ChannelTypeEnum isjava enumthat defines all the different types of channels.Channel.java package com.journaldev.design.iterator; public class Channel { private double frequency; private ChannelTypeEnum TYPE; public Channel(double freq, ChannelTypeEnum type){ ...
Returns an iterator over the elements in this set, in ascending order. C# [Android.Runtime.Register("iterator","()Ljava/util/Iterator;","GetIteratorHandler:Java.Util.INavigableSetInvoker, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null")]publicJava.Util.IIterator? Iterator...