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  • 再看看ArrayList

    public class ArrayListDemo {
        public static void main(String[] args) {
            int size = 2000000;
            List<String> list = new ArrayList<>();
            for(int i = 0;i<size;i++) {
                list.add("Just some test data");
            }
    
            long startTime = System.currentTimeMillis();
            for(int i = 0;i<size;i++) {
                list.get(i);
                if(i%10000 ==0) {
                    System.out.println("query 10000 elements spend: "+ (System.currentTimeMillis()-startTime));
                    startTime = System.currentTimeMillis();
                }
            }
        }
    }

    程序运行结果:

    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 10
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0
    query 10000 elements spend: 0

    ......
    和LinkedListWorngDemo对比可以充分说明一个问题
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  • 原文地址:https://www.cnblogs.com/danawill/p/6938675.html
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