Java自学笔记（25）：【集合】 LinkedList

List 的直接子类

构造方法：

LinkedList()  构建一个空列表

LinkedList(Collection <? extends E> c)  构建一个包含指定Collection的元素列表

常用方法演示

import java.util.LinkedList;

public class LinkedListDemo {
    
    public static void main (String[] args) {
        LinkedList<String> list = new LinkedList<String>();
        //add()
        list.add("1");
        list.add("2");
        list.add("3");
        traverse(list);
        
        list.addFirst("0");
        list.addLast("4");
        traverse(list);
        
        //print the head
        System.out.println(list.element());   //only print head
        traverse(list);    //not remove the head
        
        //get head and last
        System.out.println(list.getFirst()+" "+list.getLast());  //only print
        traverse(list);
        
        //offer()
        list.offer("5");    //add 5 
        traverse(list);
        list.offerFirst("-1");
        list.offerLast("6");
        traverse(list);
        
        //poll    //will remove the element
        System.out.println(list.pollFirst()+" "+list.pollLast());
        traverse(list);          //remove the element
        
        //pop
        System.out.println(list.pop());
        traverse(list);   //remove the head
        
        //push
        list.push("0");
        traverse(list);
        
        //remove()
        list.removeFirst();  //remove the head
        list.removeLast();   //remove the last
        traverse(list);
        list.remove();  //remove the head
        traverse(list);   
        list.remove(1);  //remove the element at 1
        traverse(list);
        
        //other
        list.add(1,"a");  //add "a" at 1
        traverse(list);
        list.removeFirstOccurrence("a");  //remove the first "a"
        traverse(list);
        list.removeLastOccurrence("4"); //remove the last 4
        traverse(list);
    }    
    public static void traverse(LinkedList<String> list) {
        //遍历
        for(int i=0;i<list.size();i++) {
            System.out.print(list.get(i)+" ");
        }
        System.out.println();
    }
}