方法clone()在Java中做什么?
java.util.ArrayList类的clone()方法返回此ArrayList实例的浅表副本(即,不复制元素本身)。
示例
import java.util.ArrayList; public class ArrayListDemo { public static void main(String args[]) { ArrayList<StringBuilder> arrlist1 = new ArrayList<StringBuilder>(); arrlist1.add(new StringBuilder("Learning-")); ArrayList arrlist2 = (ArrayList) arrlist1.clone(); StringBuilder strbuilder = arrlist1.get(0); strbuilder.append("list1, list2-both pointing to the same StringBuilder"); System.out.println("The 1st list prints: "); for (int i = 0; i < arrlist1.size(); i++) { System.out.print(arrlist1.get(i) + " "); } System.out.println("The 2nd list prints the same i.e:"); for (int i = 0; i < arrlist2.size(); i++) { System.out.print(arrlist2.get(i)); } } }
输出结果
The 1st list prints: Learning-list1, list2 - both pointing to the same StringBuilder The 2nd list prints the same i.e: Learning-list1, list2 - both pointing to the same StringBuilder