LinkedList详解可以看我的另一篇文章:Java集合:LinkedList详解 ArrayList底层基于动态数组实现,LinkedList底层基于链表实现 对于随机访问(get/set方法),ArrayList通过index直接定位到数组对应位置的节点,而LinkedList需要从头结点或尾节点开始遍历,直到寻找到目标节点,因此在效率上ArrayList优于LinkedList 对于插入和删除(add/remov...
ArrayList提供了set(int index, E element)、add(E e)、add(int index, E element)、addAll(Collection<? extends E> c)、addAll(int index, Collection<? extends E> c)这些添加元素的方法。下面我们一一讲解: set(int index, E element):该方法首先调用rangeCheck(index)来校验index变量是否超出数组范围,...
list.set(2, "a"); 让我们举一个示例程序,我们将使用 remove() 方法从列表中删除一个元素。 程序源代码 2: package ArrayListTest; import java.util.ArrayList; public class RemoveEx { public static void main(String[] args) { // Create a generic Arraylist object of String type. // This means...
* It maintains a notion of a current position and of * course the implicit reference to the MyArrayList. */ private class ArrayListIterator implements java.util.Iterator<AnyType> { private int current = 0;//记录当前的值 private boolean okToRemove = false; public boolean hasNext() { return...
Thesize,isEmpty,get,set,iterator, andlistIteratoroperations run in constant time. Theaddoperation runs inamortized constant time, that is, adding n elements requires O(n) time. All of the other operations run in linear time (roughly speaking). The constant factor is low compared to that for...
safe variant ofArrayListin which all mutative operations (add, set, and so on) are implemented by making a fresh copy of the underlying array. This class is very useful when we cannot or do not want to synchronize the traversals of the arraylist. It is part of thread-safe Java ...
SubList这个类中单独定义了set、get、size、add、remove等方法。 当我们调用subList方法的时候,会通过调用SubList的构造函数创建一个SubList,那么看下这个构造函数做了哪些事情: SubList(AbstractList<E> parent,int offset, int fromIndex, int toIndex) { this.parent = parent; this.parentOffset = fromIndex; this...
The Java ArrayList subList() method extracts a portion of the arraylist and returns it. In this tutorial, we will learn about the ArrayList subList() method with the help of examples.
Thesize,isEmpty,get,set,iterator, andlistIteratoroperations run in constant time. Theaddoperation runs inamortized constant time, that is, adding n elements requires O(n) time. All of the other operations run in linear time (roughly speaking). The constant factor is low compared to that for...
In addition to implementing the List interface, this class provides methods to manipulate the size of the array that is used internally to store the list. (This class is roughly equivalent to Vector, except that it is unsynchronized.) The size, isEmpty, get, set, iterator, and listIterator...