1, Data type 1. Basic data type meaning: The data of the corresponding type is assigned to the variable of the corresponding type Automatic type lifting: Small ----- > Large It can be stored normally, but it may cause a waste of memory Cast type: Large ----- > small Can not occur, which may cause loss of accuracy Small range type variable ...
Posted by mihomes on Thu, 03 Mar 2022 15:36:38 +0100
I believe that the biggest motivation for many people to learn distributed locks is not their own system needs, but the needs of interviewers... Of course, this also shows that the distribution lock is very important. It is often used as an examination question. Before learning, we need to clarify several questions.
Posted by Virii on Thu, 03 Mar 2022 13:15:01 +0100
Mybatis personal summary notes
01 basic information
Mybatis is the SQL mapping frameworkThis object can be mapped into a row of data in the databaseDevelopers only need to provide sql, process sql through Mybatis, and finally get the List collection or Java objectsMybatis is a semi-automatic ORM mapping tool, which is called semi-automa ...
Posted by simongcc on Thu, 03 Mar 2022 12:38:29 +0100
Arthas online analysis, diagnosis and tuning tool
In the past, when we wanted to troubleshoot online problems, we usually used the tuning tools and commands provided by jdk. The most common is the dump online log, which is then downloaded locally and imported into the jvisual VM tool. There are many changes in this operation. The Arhtas tool d ...
Posted by oh_maestro on Thu, 03 Mar 2022 11:58:39 +0100
Introduction to JSON
You can only use double quotation marks, not single quo ...
Posted by Chappers on Thu, 03 Mar 2022 09:37:32 +0100
While the code is rolling, a message pops up in the company's chat tool:
"Brother wolf, my machine always FGC frequently..."
I quickly opened the dialog box and replied with a witty expression
Then continue silently.
Then, the little partner smashed a GC log
2019-09-17T20:33:57.889+0800: 4753520.554: [Full GC (Metadata GC Th ...
Posted by harshilshah on Thu, 03 Mar 2022 06:59:15 +0100
This article is based on PY3 8，system win10，numpy1.12.
np is the abbreviation of numpy.
1, Summary of reference sources and basic knowledge
Performance comparison between python built-in max() and min() functions and Numpy built-in max() and min() functions
Based on python 2.7.15 and system win10, the above article draws ...
Posted by elacdude on Thu, 03 Mar 2022 06:19:12 +0100
1 what is LRU cache
LRU (Least Recently Used) algorithm is an elimination strategy. In short, the implementation is as follows: put some elements into a container with fixed capacity for access. Due to the limited capacity of the container, the container should ensure that the elements that have been used recently are always in the contain ...
Posted by lpxxfaintxx on Thu, 03 Mar 2022 04:51:19 +0100
Spring circular dependency
What is circular dependency?
Under what circumstances can circular dependencies be handled?
Basic introduction and the essence of circular dependency
what？ The essence of the problem is actually two sum!
How to get to getSingleton method
Simple circular dependency (no AOP)
Call getSingleton(beanName ...
Posted by jimmyt1988 on Wed, 02 Mar 2022 16:25:13 +0100