import java.util.ArrayList; import java.util.List; public class CollectionMethod { public static void main(String[] args) { //创建ArrayList,使用接口接收 List list = new ArrayList(); //add:添加单个元素 list.add("java"); //字符型 list.add(10); //整型 相当于list.add(new Integer(10)) ...
Boolean b = list1.addAll(2,list2); //把list2元素插入到list1中索引位置为2处。 System.out.println("list1:" + list); // [aaa,bbb,星期一,星期二,ccc] System.out.println("list1集合是否发生变化:" + b); // true b = list1.addAll(2,list3); //把list3元素插入到list1中索引位置为...
The size, isEmpty, get, set, iterator, and listIterator operations run in constant time. The add operation runs in amortized 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 compare...
LinkedList 继承自 AbstractSequentialList。 AbstractSequentialList 又继承自AbstractList,并且基于 iterator 实现了默认增删改查操作。 再回过头来看 LinkedList,LinkedList 还实现了Deque(双向队列)接口,双向队列后面我们会单独去学习,这里不再做过多的赘述。 再来看看成员变量~~ size 链表元素个数 first 第一个元素 last...
list1.add("c"); list.addAll(list1); // It will add group of elements at the end of the last element in the list. The last element is z. So, after z, it will add list1 as shown in above figure. 4.boolean addAll(int index, Collection c):此方法用于在列表中的特定位置添加/插...
transient Node<E> first; // 链表的首节点 transient Node<E> last; // 链表的末节点 LinkedList构造方法: 1/**2* Constructs an empty list.3*/4public LinkedList() {5}67/**8* Constructs a list containing the elements of the specified9* collection, in the order they are returned by the ...
public class MyArrayList implements List { private Object[] elements; private int curr; // 先给数组分配16个长度 public MyArrayList() { elements = new Object[16]; curr = 0; } @Override public int size() { return curr; } @Override ...
java.util.List 接口继承于 Collection 接口,与Map最大的不同之处,在于它属于单列集合,相当于一个列表,有以下这些特点:
Synopsis: Collection.sort defers now defers to List.sortPreviously Collection.sort copied the elements of the list to sort into an array, sorted that array, then updated list, in place, with those elements in the array, and the default method List.sort deferred to Collection.sort. This was...
Returns an array containing all of the elements in this list in proper sequence (from first to last element). <T> T[]toArray(T[] a) Returns an array containing all of the elements in this list in proper sequence (from first to last element); the runtime type of the returned array ...