importjava.util.ArrayList;importjava.util.HashSet;publicclassFindElements{publicstaticvoidmain(String[]args){// Step 1: 创建并初始化一个 ArrayListArrayList<String>list=newArrayList<>();list.add("Apple");list.add("B
println(array.remove(3));// public E set(intindex,E element)：修改指定索引处的元素，返回被修改的元素 System.out.println(array.set(1,"javaee"));// 发生索引越界异常 IndexOutOfBoundsException System.out.println(array.set(3,"javaee"));// public E get(intindex)：返回指定索引处的元...
array.add("java");//public void add(int index,E element):在此集合中的指定位置插入指定的元素array.add(1,"javase");//array.add(3,"javaee");//IndexOutOfBoundsException//array.add(4,"javaee");//输出集合System.out.println("array:"+array); } } 2、ArrayList 类常用方法 package com.it...
private int findElement(Object o, int qiShi, int buChang) {//封装有一个查找对象方法 for (int i = qiShi; i >= 0 && i < size; i += buChang) { if ((o != null) ? o.equals(data[i]) : o == data[i]) { return i; } } return -1; } private boolean jiaoji(myArrayList o...
("javaee")); // public E remove(int index):删除指定索引处的元素,返回被删除的元素 System.out.println(array.remove(1)); // 发生索引越界异常IndexOutOfBoundsException System.out.println(array.remove(3)); // public E set(int index,E element):修改指定索引处的元素,返回被修改的元素 System....
If you want to find all elements satisfying a predicate, you may filter collection using Java 8Stream API(read more about ithere) usingPredicatelike this: Set<String> matchingStrings =newHashSet<>(Arrays.asList("a","c","9"));
(int index,E element):修改指定索引处的元素,返回被修改的元素 // System.out.println(array.set(1,"javaee")); //IndexOutOfBoundsException // System.out.println(array.set(3,"javaee")); //public E get(int index):返回指定索引处的元素 // System.out.println(array.get(0)); // System....
ArrayList<String>names;names.add("John");#Output:#Exceptionin thread"main"java.lang.NullPointerException Java Copy In this example, we declared an ArrayList but didn’t initialize it. When we tried to add an element to it, Java threw a ‘NullPointerException’. ...
java有序键值对list java arraylist有序,Java中的ArrayList用于存储动态调整大小的元素集合。与固定大小的数组相反,当向其添加新元素时,ArrayList会自动增加其大小。ArrayList是Java的收集框架的一部分,并实现Java的List接口。 以下是有关Java中ArrayList的几点注
AI代码解释 publicclassArrayListDemo02{publicstaticvoidmain(String[]args){//创建集合ArrayList<String>array=newArrayList<String>();//添加元素array.add("hello");array.add("world");array.add("java");//public boolean remove(Object o):删除指定的元素,返回删除是否成功// System.out.println(array.remov...