ArrayList, LinkedList, Vector, Stack使用
import java.util.*;
import java.lang.Class;
/*
* @desc 对比ArrayList和LinkedList的插入、随机读取效率、删除的效率
*
* @author skywang
*/
public class ListCompareTest {
private static final int COUNT = 100000;
private static LinkedList linkedList = new LinkedList();
private static ArrayList arrayList = new ArrayList();
private static Vector vector = new Vector();
private static Stack stack = new Stack();
public static void main(String[] args) {
// 换行符
System.out.println();
// 插入
insertByPosition(stack) ;
insertByPosition(vector) ;
insertByPosition(linkedList) ;
insertByPosition(arrayList) ;
// 换行符
System.out.println();
// 随机读取
readByPosition(stack);
readByPosition(vector);
readByPosition(linkedList);
readByPosition(arrayList);
// 换行符
System.out.println();
// 删除
deleteByPosition(stack);
deleteByPosition(vector);
deleteByPosition(linkedList);
deleteByPosition(arrayList);
}
// 获取list的名称
private static String getListName(List list) {
if (list instanceof LinkedList) {
return "LinkedList";
} else if (list instanceof ArrayList) {
return "ArrayList";
} else if (list instanceof Stack) {
return "Stack";
} else if (list instanceof Vector) {
return "Vector";
} else {
return "List";
}
}
// 向list的指定位置插入COUNT个元素，并统计时间
private static void insertByPosition(List list) {
long startTime = System.currentTimeMillis();
// 向list的位置0插入COUNT个数
for (int i=0; i<COUNT; i++)
list.add(0, i);
long endTime = System.currentTimeMillis();
long interval = endTime - startTime;
System.out.println(getListName(list) + " : insert "+COUNT+" elements into the 1st position use time：" + interval+" ms");
}
// 从list的指定位置删除COUNT个元素，并统计时间
private static void deleteByPosition(List list) {
long startTime = System.currentTimeMillis();
// 删除list第一个位置元素
for (int i=0; i<COUNT; i++)
list.remove(0);
long endTime = System.currentTimeMillis();
long interval = endTime - startTime;
System.out.println(getListName(list) + " : delete "+COUNT+" elements from the 1st position use time：" + interval+" ms");
}
// 根据position，不断从list中读取元素，并统计时间
private static void readByPosition(List list) {
long startTime = System.currentTimeMillis();
// 读取list元素
for (int i=0; i<COUNT; i++)
list.get(i);
long endTime = System.currentTimeMillis();
long interval = endTime - startTime;
System.out.println(getListName(list) + " : read "+COUNT+" elements by position use time：" + interval+" ms");
}
}
结果：
Stack : insert 100000 elements into the 1st position use time：1640 ms
Vector : insert 100000 elements into the 1st position use time：1607 ms
LinkedList : insert 100000 elements into the 1st position use time：29 ms
ArrayList : insert 100000 elements into the 1st position use time：1617 ms
Stack : read 100000 elements by position use time：9 ms
Vector : read 100000 elements by position use time：6 ms
LinkedList : read 100000 elements by position use time：10809 ms
ArrayList : read 100000 elements by position use time：5 ms
Stack : delete 100000 elements from the 1st position use time：1916 ms
Vector : delete 100000 elements from the 1st position use time：1910 ms
LinkedList : delete 100000 elements from the 1st position use time：15 ms
ArrayList : delete 100000 elements from the 1st position use time：1909 ms
