The Enum enumeration class only needs to add annotations to obtain the corresponding enumeration type and implement the front-end acquisition interface.

Foreword: This function is implemented with reference to how to use java enumerations efficiently and elegantly, and further transforms the use of enumerations in it. Why should we transform the enumeration class? The biggest pain point is code redundancy: The most common method is to traverse to match and then obtain the type and information […]

Weekly competition 361 (simulation, enumeration, memory search, counting the number of subarrays (prefix sum + hash), LCA application questions)

Article directory Weekly competition 361 [2843. Count the number of symmetric integers](https://leetcode.cn/problems/count-symmetric-integers/) simulation [2844. Minimum operations to make a special number](https://leetcode.cn/problems/minimum-operations-to-make-a-special-number/) Memoized search enumerate [2845. Count the number of interesting subarrays](https://leetcode.cn/problems/count-of-interesting-subarrays/) prefix sum + hash table (interval count is often prefix sum) [2846. Edge weight equal queries](https://leetcode.cn/problems/minimum-edge-weight-equilibrium-queries-in-a-tree/) LCA application questions Weekly Competition 361 2843. Count […]

Simple and easy to understand JVM series (3) – root node enumeration and related algorithm implementation details

1. Background This part of knowledge appears frequently during the interview process. Understanding this part of knowledge can, on the one hand, give us a better understanding of the next garbage collector. On the other hand, we can delve deeper into the details of these methods to avoid just staying on the surface concepts. Then […]

Custom types: structure, enumeration, union

Table of Contents Structure 1 Declaration of structure 1.1 Basic knowledge of structure 1.2 Declaration of structure 1.3 Special Statement 1.4 Self-reference of structures 1.5 Definition and initialization of structure variables 1.6 Structure memory alignment 1.7 Modify the default alignment number 1.8 Structure parameter passing 2. bit segment 2.1 What is a bit segment? 2.2 […]

MybatisPlus extended functions code generation logical deletion general enumeration field type processor configuration encryption

MybatisPlus Core Functions Conditional Constructor Custom SQL Service Interface Static Tool_Soft Worker’s Blog-CSDN Blog 3. Extended functions 3.1. Code generation After using MybatisPlus, the basic Mapper, Service, and PO codes are relatively fixed, and it is troublesome to write them repeatedly. Therefore, MybatisPlus officially provides a code generator that generatesPO based on the database table […]

Best practices for MyBatisPlus enumeration classes (very typical and efficient way to write enumeration classes)

Table of Contents 1. MyBatisPlus enumeration class best practices 2. The role and problems of enumeration classes 3. MyBatisPlus annotation implementation of enumeration best practices 4. In simple terms 5. Let’s look at a complete enumeration class example using the above annotations: (1) Enumeration class: (2) DTO class: 6. Explain in detail based on the […]

3. Enumeration and plug-in detection of video devices

1. Preface This chapter mainly describes how to obtain the device name and guid, identify the collection format of the collection device, and plug and unplug the device. The device list and attributes are obtained using directshow (the subsequent MediaFoundation cannot obtain the OBS camera) Device plugging and unplugging uses QT to capture system messages. […]

Custom types: structure, enumeration, union

Table of Contents Structure Basic knowledge of structures structure declaration special statement Self-referencing of structures Definition and initialization of structure variables Structure memory alignment Modify the default alignment number Structure parameter passing Rank What is bit segment Bit segment memory allocation Cross-platform issues with bit segments Bit segment applications enumerate Definition of enumeration type Advantages […]

Java: Use of enumeration values (data dictionary) in Springboot and React

Directory 1. Development needs 2. Realize the effect 3. Backend code 4. Front-end code 5. Interface data 6. Complete code 7. Reference articles 1. Development requirements During the development and use process, four roles are usually involved: database administrator, back-end developer, front-end developer, and browser The database uses int type values for storage (eg: 0, […]