Programmer Group

1. Prepare the data first. The data here is not the data directly found in the database, but a copy of the data found. The data of the two does not affect each other, so that the copied data can be modified. (1) define a method (implementation class method of service layer) of data found from database, omit the method of mapper mapping file and ...

concept apply call and bind allow assignment and invocation of functions/methods belonging to one object for different objects.They can also change the direction of this within the function. Difference apply and call receive parameters in different forms Both apply and call call call call functions directly and get the result of their ...

1, Spring's transaction mechanism All data access technologies have transaction processing mechanisms, which provide API s to enable transactions, commit transactions to complete data operations, or roll back data in case of errors. Spring's transaction mechanism is to use a unified mechanism to handle transactions of different data a ...

Single layer graph slide verification code of selenium and PIL How to crack the slide verification code preparation in advance Code operation How to crack the slide verification code There are various mechanisms of anti climbing on the market, among which the sliding verification code is divided into two-layer graph ...

The data in the tableView below is downloaded from the network (server). Normally, clicking each cell will play the video. The url address of the video here is wrong. Therefore, the playback is wrong. Normally, the video can be played! Format online http://tool.oschina.net/codeformat/json The renderings are as follows: This project u ...

problem Design a person class with the following conditions: 1) Define the protected attribute: name (name), age (age), sex (gender) 2) Define static attribute: num (used to calculate the number of instantiated persons) 3) Define a constructor that outputs "I am a person" when an object is created and adds 1 to num; 4) Define a dest ...

1, Simple entry level tree menu implementation (pure background logic) 1. Introduction (1) Development environment　　IDEA + JDK1.8 + mysql 1.8　　SpringBoot 2.2.6 + mybatis-plusHere, it is only developed in the background (json data is returned), which will be explained in the subsequent presentation of the front page. (2) Data sheetAs follows ...

ESLint   whether it's a multi person collaboration or a personal project, code specification is very important. This can not only avoid basic syntax errors to a great extent, but also ensure the readability of the code. preparation 1, VSCode ESLint plug in The ESLint plug-in is used to display some error prompts in the editor accordi ...

1 I am Queen of the Jing King of Zhongshan Hello, my name is Li Dahammer, and I am an unrivalled actor. I am about to participate in a stage play called The Romance of the Three Kingdoms, directed by Mr. Luo Guanzhong, an old man whose coffin cannot be pressed down.And I, Uncle Liu, who is about to play one of the three leading characters, hey ...

Preface With the popularization and development of industrial Internet of Things and Internet technology, the way of artificial filling has been gradually replaced by mechanical equipment.Industrial manufacturers are increasingly demanding higher standards and stringent requirements for equipment in order to reduce misoperation, improve equipme ...