Two methods and comparison of Java reading map

preface

There are many ways to traverse the map in Java. In this article, let's take a look at the two methods of reading map in Java and the comparison between the two methods.

1、 Traverse map method a

2、 Traverse map method B

3、 Analytic traversal method

Method a: read map once in traversal Entry, and then get the value directly.

Method B: Based on keyset, first traverse, and then read information from the map.

4、 Performance test

Test results:

It can be seen that 1000000 data are stored in the map and traversed in this data set. Nearly double the performance difference in efficiency.

5、 Summary

Well, that's all the content of this article. You can see that method a is more efficient overall. It is generally recommended that you use method a. I hope the content of this article can bring some help to your study or work.