lock(this) is actually a pit

In this case, only one machine is considered, and multiple servers can use distributed locks. For thread safety reasons, you may see the emergence of lock in many scenarios, especially in the processing of fund class. But does lock(this) really meet your needs? Here is an example We don't have much theoretical knowledge. Back to the business s ...

Posted on Fri, 07 Feb 2020 07:59:30 -0800 by jchemie

java to implement mailbox verification (a simplified operation and idea, many things must be read)

I don't know what email verification is all the time. I always think it's amazing (because I almost never use email) that this function has been successfully implemented under the leadership of the big guy. I don't need to say much to start the operation: Technology I use: java,maven,mysql, some relat ...

Posted on Thu, 06 Feb 2020 23:52:16 -0800 by dch27

How do I bind RadioButtons to enumeration?

I have an enumeration like this: public enum MyLovelyEnum { FirstSelection, TheOtherSelection, YetAnotherOne }; I get a property in DataContext: public MyLovelyEnum VeryLovelyEnum { get; set; } I got three RadioButtons in the WPF client. <RadioButton Margin="3">First Selection</RadioButton> <RadioButton M ...

Posted on Thu, 06 Feb 2020 22:58:35 -0800 by davestewart

Python Automation Crawling of Urban Distance [Small Project Required]

Create a database locally, store Excel data in city table, and record all prefecture-level cities and counties, county-level cities and districts of | Hubei Province as sample table data.Using python's xlrd package, define process_data package to store operation excel data, generate classes of sql statements, define op_postgresql package to st ...

Posted on Thu, 06 Feb 2020 19:49:16 -0800 by Right Wing Liberal

Redis practice String of data structure storage object of practice

Overview: the related content of this series of blog articles comes from the actual combat course recorded by debug in person: Introduction to Redis technology and application scenario practice (SpringBoot2.x + red packet system design and practice) , interested partners can click to learn by themselves (after all, mastering technology in the ...

Posted on Thu, 06 Feb 2020 01:44:45 -0800 by psycho_somatic

The use and principle of ThreadLocal

I. overview The simple understanding of ThreadLocal is to share resources for a thread, save some resources in the thread through set() method, and then obtain this resource through get method. It solves the problem of sharing the same object or variable in the same thread and method of different clas ...

Posted on Wed, 05 Feb 2020 23:24:57 -0800 by vhaxu

centos7 yum install mysql5.7

By default, MariaDB is installed in CentOS, which is a branch of MySQL. However, in order to meet the needs, MySQL should be installed in the system, and MariaDB can be directly overwritten after the installation. 1 download and install MySQL's official Yum Repository [root@centos7 ~]# wget https:/ ...

Posted on Wed, 05 Feb 2020 04:45:41 -0800 by emopoops

Several case s where transactions for the SpringBoot series of tutorials do not work

Several case s where transactions for the SpringBoot series of tutorials do not work Previous posts on declarative transactions @Transactional use posture, knowing only that the correct posture may not be enough, and what scenarios do not work to avoid pit mining.This article will focus on a few case s where transactions do not take effect & ...

Posted on Tue, 04 Feb 2020 17:03:37 -0800 by Rupuz

Database - index

Database - index MySQL's official definition of Index is: Index is a data structure that helps MySQL obtain data efficiently. There is a big difference between 0.5s for data acquisition and 0.001s for data acquisition! Therefore, it is necessary to study index! The essence of index: index is data stru ...

Posted on Tue, 04 Feb 2020 09:52:53 -0800 by peterj

Fastadmin step in the pit diary-2. Magic change form

Fastadmin step in the pit diary-2. Magic change form After days and nights of searching, we can finally slowly start this, step on a few pits, and record it Pit 1 - the foreground cannot display emoji characters The first few emoji are two bytes, which can be displayed normally in the default double ...

Posted on Tue, 04 Feb 2020 04:27:03 -0800 by colforbin05