List 的 subList方法注意点

package com.dzh.Collections;


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


/**
 * 
 * @author mocking
 * warning 慎用List的subList(fromIndex,toIndex)方法,subList的值发生改变,list的值会发生相应的改变
 * list 的结构发生变化时,subList方法会抛出 java.util.ConcurrentModificationException 异常
 * subList的结构发生变化时,list也会发生相应的变化
 */
public class SubListTest {
public static void main(String[] args) {
List<Integer> list = new ArrayList<>();
for(int i = 0;i< 10;i++)
list.add(i);
List<Integer> subList = list.subList(0, 4);
/*List<Integer> newList = subList;*/
List<Integer> newList = new ArrayList<>();
for(int i = 0;i < subList.size();i++)
newList.add(subList.get(i));
System.out.println("subList:"+subList);
System.out.println("list:"+list);
System.out.println("newList:"+newList);

subList.remove(3);
System.out.println("subList:"+subList);
System.out.println("list:"+list);
System.out.println("newList:"+newList);

/* list.remove(5);
System.out.println("subList:"+subList);
System.out.println("list:"+list);
System.out.println("newList:"+newList);*/

/* subList.clear();
for(int i = 1;i < 5;i++)
subList.add(i);
System.out.println("sublist---"+subList);
System.out.println("list---"+list);
System.out.println("newList---"+newList);*/

}


}

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转载自blog.csdn.net/dashujua/article/details/78548603
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