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preface It was in 2002, and MySQL 4.1 began to support UTF-8 coding RFC 2279 It is stipulated that the code uses 1 ~ 6 bytes to store a single character, and MySQL developers checked it in September of the same year Source code The UTF-8 encoding is changed from the maximum 6 bytes to 3 bytes, so there is the current UTF8MB3. As we all know, U ...

Today, let's talk about concurrent linkedqueue The ConcurrentLinkedQueue we are going to learn today does not implement the BlockingQueue interface. It is a thread safe and unbounded non blocking queue that completely uses CAS operations. Structural composition public class ConcurrentLinkedQueue<E> extends AbstractQueue<E> ...

Application scenario 1. Asynchronous processing Scenario: after registration, users need to send e-mails and text messages after successful registration. There are two traditional methods: Serial mode: after the registration information is written into the database, send the email of successful registration. After the email is sent successf ...

The initialization process of MyBatis is to generate some necessary objects and put them into the Spring container. The question is what objects are generated by this process? When MyBatis initialization fails, how to correctly find the entry point to analyze the problem? This paper will introduce these problems. Based on MyBatis 3 and Spr ...

Introduction Learning English is difficult, but it's fun———— Learning English ​ Do you need to read the original English web pages, news and documents? Do you always need to stop to look up the dictionary, stumble, or even find it difficult to continue? Xiaobian often encounters this problem. Although learning Python ...

When we do technology pre research / business start-up, Functionality is the most important. It's ok if we can run through it. For the most popular C/S architecture, the following architecture is the simplest model that can meet functional requirements:However, with the development of our business, Scalability and high availability will gradual ...

Detective reasoning Title Description Mingming recently fell in love with the detective cartoon Conan and indulged in the reasoning game, so he called a group of students to play the reasoning game. The content of the game is like this. Mingming's classmates first discuss that one of them should act as a criminal (without knowing it). Mingmin ...

As we all know, the underlying layer of AOP is dynamic agent, and there are two ways to implement dynamic agent in Java: Dynamic agent based on JDKDynamic agent based on Cglib The biggest difference between the two is that the JDK based dynamic proxy needs the proxy object to have an interface, while the Cglib based dynamic proxy does not need ...

IoC What is IoC? IoC is the abbreviation of inversion of control. Note that it is a technical idea. It describes the creation and management of objects. Traditional development methods: for example, if class a depends on class B, it often creates a new object of class B in class A.IoC development method: we don't need to go to the new object ...

preface Use Python to identify the graphic verification code to realize automatic login. No more nonsense. development tool Python version: 3.6.4 Related modules: re； numpy module; pytesseract module; selenium module; And some Python built-in modules. Environment construction Install Python and add it to the environment variable. pip ...