Fengdi Li | 李锋镝

Original link: https://www.lifengdi.com/archives/course/java/3907 Variables What are variables? Variables are the algebraic concept of junior high school mathematics, such as a simple equation, x and y are variables: y=x^2+1 In Java, variables are divided into two types: basic type variables and reference type variables. Let’s start by discussing basic types of variables. In Java, variables must […]

Original link: https://www.lifengdi.com/archives/course/java/3906 Let’s first analyze a complete Java program, what is its basic structure: /** * Comments that can be used to automatically create documents */ public class Hello { public static void main(String[] args) { // Output to the screen Text: System.out.println(“Hello, world!”); /* Multi-line comments start comment content Comment end */ }

Original link: https://www.lifengdi.com/archives/course/3905 Java was originally a programming language developed by James Gosling (Gao Commander, known as the father of Java) of SUN (which has been acquired by Oracle) in the early 1990s. It was originally named Oak and aimed at small The embedded application of home appliances, the result is that the market has

Original link: https://www.lifengdi.com/archives/daily/3904 Seeing from a distance that you are about to cross the road, then immediately slow down and stop to give way. How can I delay the time of a car of people on my own? It’s quite fresh once or twice. It makes me feel a little nervous every time. I have

Original link: https://www.lifengdi.com/archives/transport/3897 Preparations: Jetbrains series products reset trial plugin MyBatisCodeHelperPro ​(Marketplace Edition)​ idea Step 1 Method 1) Plugin Market Installation: Manually add third-party plugin warehouse address in Settings/Preferences… -> Plugins: http://plugins .zhile.io search: IDE Eval Reset plugin to install. If you can’t find it, please pay attention to whether you have done the previous

Original link: https://www.lifengdi.com/archives/transport/3890 The two annotations @Resource and @Autowired are used to implement Bean dependency injection in the Spring ecosystem. Let’s talk about the two annotations @Autowired and @Resource respectively. Flashed [@Autowired’s role detailed explanation] a few words. First of all, @Autowired is an annotation provided in Spring. By default, Bean dependency injection is implemented

Original link: https://www.lifengdi.com/archives/article/3888 Background When we use RocketMQ, the @PostConstruct annotation is generally used for Consumer startup. (@PostConstruct: used to execute methods that need to be executed after dependency injection is performed when performing any initialization.), or use bean configuration. The configuration is as follows: Producer configuration Configure all producers in the configuration class, inject

Original link: https://www.lifengdi.com/archives/daily/3881 Whether it is a big friend or a small child~~Be happy~~ Unless specified, it is Li Fengdi’s blog – LiFengdi.Com original article, the reprint must indicate this article link in the form of a link Link to this article: https://ift .tt/resSfc4 This article is reprinted from: https://www.lifengdi.com/archives/daily/3881 This site is for inclusion

Original link: https://www.lifengdi.com/archives/daily/3876 I originally listened to Jay’s songs, but NetEase Cloud doesn’t have the copyright and can go to Migu. As a result, Migu has to become a member now… It’s not that I have to prostitute for nothing, it’s mainly because it feels a little unworthy to open a member for this alone.

Original link: https://www.lifengdi.com/archives/daily/3874 The expression of the comment is accelerated by jsdelivr, but it seems to be hung up now… I have been unable to access it for the past few days, which has caused the page opening speed to become extremely slow! It’s hard to do it~ I’ll see if there are any alternatives

Original link: https://www.lifengdi.com/archives/daily/3871 Hey… I officially started working from home today… I got up at 7:50 in the morning, porridge was boiled in the pot, and then I started to wash. At 8:20, the porridge was cooked, and then went downstairs to line up to make nucleic acid. At 8:40, I came back from the

The reason is that I recently wrote a python script. Since the sub-database and sub-table are used, the database and table names need to be dynamically calculated according to the sub-table fields. At first, the %s placeholder was used directly in SQL. Later, it was found that an error was reported and the SQL statement

Foreword In daily development, we often copy and paste strings such as JSON, XML, HTML, SQL, Regex into our code, and these strings often contain a lot of quotation marks”, we must escape all quotation marks one by one character to escape. This escape is cumbersome and error-prone, and when we need to replace these