圖解：

原始碼：

public class ArrayList<E> extends AbstractList<E>
        implements List<E>, RandomAccess, Cloneable, java.io.Serializable

1 RandomAccess：隨機訪問

 1 public static void main(String[] args) {
 2         ArrayList<String> list = new ArrayList();
 3         for (int i = 0; i < 100000; i++) {
 
 4             list.add("odd Point" + i);
 5         }
 6         //隨機訪問
 7         long start = System.currentTimeMillis();
 8         for (int i = 0; i < list.size(); i++) {
 9             list.get(i);
10         }
11         long end = System.currentTimeMillis();
12         System.out.println("隨機訪問時間："+(end-start));
 
13 
14         //順序訪問
15         start = System.currentTimeMillis();
16         Iterator<String> iterator = list.iterator();
17         while(iterator.hasNext()){
18             iterator.next();
19         }
20         end = System.currentTimeMillis();
21         System.out.println("順序訪問時間："+(end-start));
 
22 }

2 Cloneable：可克隆

3 Serializable：可序列化