本文解释了ArrayList和LinkedList之间的区别，在这种情况下，我们应该选择其中一种。

ArrayList和Linked list由于继承了同一个接口—list，所以共享相同的属性。但是ArrayList和LinkedList有什么区别呢？简单地说–ArrayLists对于写一次读多个操作是很好的，但是不擅长从前面或者中间添加/删除。另一方面，插入LinkedList更好。

ArrayList vs LinkedList性能示例

下面的示例演示

add

,

set

和

remove

在ArrayList和LinkedList上使用相同数据的操作

package theitroad.local;

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

public class ArrayListVsLinkedListExample {

	private static final int ELCOUNT = 50000;

	public static void main(String[] args) {

		List<String> alist = new ArrayList<String>();
		List<String> llist = new LinkedList<String>();

		//Insertion ////////////////

		//ArrayList
		long start = System.currentTimeMillis();
		for (int i = 0; i < ELCOUNT; i++) {
			alist.add("element #" + i);
		}
		long totalTimeMs = System.currentTimeMillis() - start;
		System.out.println("Adding 50K elements in ArrayList took " + totalTimeMs + " ms");

		//LinkedList
		start = System.currentTimeMillis();
		for (int i = 0; i < ELCOUNT; i++) {
			llist.add("element #" + i);
		}
		totalTimeMs = System.currentTimeMillis() - start;
		System.out.println("Adding 50K elements in LinkedList took " + totalTimeMs + " ms");

		//Modification /////////////

		//ArrayList
		start = System.currentTimeMillis();
		for (int i = 0; i < ELCOUNT; i++) {
			alist.set(i, "modified element #" + i);
		}
		totalTimeMs = System.currentTimeMillis() - start;
		System.out.println("Modifying 50K elements in ArrayList took " + totalTimeMs + " ms");

		//LinkedList
		start = System.currentTimeMillis();
		for (int i = 0; i < ELCOUNT; i++) {
			llist.set(i, "modified element #" + i);
		}
		totalTimeMs = System.currentTimeMillis() - start;
		System.out.println("Modifying 50K elements in LinkedList took " + totalTimeMs + " ms");

		//Removal //////////////////

		System.out.println("ArrayList size before removal " + alist.size());
		System.out.println("LinkedList size before removal " + llist.size());

		//ArrayList
		start = System.currentTimeMillis();
		for (int i = 0; i < ELCOUNT; i++) {
			alist.remove(0);
		}
		totalTimeMs = System.currentTimeMillis() - start;
		System.out.println("Removing 50K elements in ArrayList took " + totalTimeMs + " ms");

		//LinkedList
		start = System.currentTimeMillis();
		for (int i = 0; i < ELCOUNT; i++) {
			llist.remove(0);
		}
		totalTimeMs = System.currentTimeMillis() - start;
		System.out.println("Removing 50K elements in LinkedList took " + totalTimeMs + " ms");

		System.out.println("ArrayList size after removal " + alist.size());
		System.out.println("LinkedList size after removal " + llist.size());
	}

}

下面是执行示例代码的输出。不同的计算机配置结果会有所不同

Adding 50K elements in ArrayList took 10 ms
Adding 50K elements in LinkedList took 7 ms
Modifying 50K elements in ArrayList took 7 ms
Modifying 50K elements in LinkedList took 6315 ms
ArrayList size before removal 50000
LinkedList size before removal 50000
Removing 50K elements in ArrayList took 135 ms
Removing 50K elements in LinkedList took 4 ms
ArrayList size after removal 0
LinkedList size after removal 0

正如我们将在上面的输出中看到的：

LinkedList在访问和修改元素时明显较慢

LinkedList添加元素的速度较慢

LinkedList从列表开头删除元素的速度要快得多

ArrayList插入新元素的速度较慢

访问ArrayList的速度非常快

从ArrayList的开头删除元素的速度明显较慢