Java中LinkedList和ArrayList的效率分析

package com.example.SpringBootpf4jservice;

import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import java.util.Random;

public class ListPerfORManceTest {
    public static void main(String[] args) {
        List<Integer> arrayList = new ArrayList<>();
        List<Integer> linkedList = new LinkedList<>();
        Random rand = new Random();

        // 用随机整数填充列表。
        for (int i = 0; i < 100000; i++) {
            int num = rand.nextInt();
            arrayList.add(num);
            linkedList.add(num);
        }

        // 测量在每个列表的开头插入元素所需的时间。
        long startTime = System.currentTimeMillis();
        for (int i = 0; i < 1000; i++) {
            arrayList.add(0, rand.nextInt());
        }
        long endTime = System.currentTimeMillis();
        System.out.println("ArrayList insert time: " + (endTime - startTime) + "ms");

        startTime = System.currentTimeMillis();
        for (int i = 0; i < 1000; i++) {
            linkedList.add(0, rand.nextInt());
        }
        endTime = System.currentTimeMillis();
        System.out.println("LinkedList insert time: " + (endTime - startTime) + "ms");

    }
}