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[STM32] Several message reception filtering modes for STM32 CANFD peripherals

In Controller Area Network (CAN) systems, correctly configuring message filters is critical to effectively manage network communications. Especially when using the Flexible Data-rate Controller Area Network (FDCAN), choosing the appropriate filter type can greatly improve network efficiency and message processing speed. The CAN peripheral of the STM32G47x chip has the following reception message filtering methods: […]

Spring transaction AOP causes transaction failure problem

Situation Description First, AOP was enabled, and transactions were enabled at the same time. The TransactionAspect below is a simple AOP aspect with an Around notification. @Aspect @Component public class TransactionAspect {<!– –> @Pointcut(“execution(* com.qhyu.cloud.datasource.service.TransactionService.*(..))”) // the pointcut expression private void transactionLogInfo() {<!– –>} // the pointcut signature /** *Title: around<br> * Description: This Around […]

SpringBoot: SpEL makes complex permission control easy!

The path to growth as a programmer Internet/Programmer/Technology/Data Sharing focus on This article should take approximately 6 minutes to read. From: juejin.cn/post/7226674759626571833 1 Introduction 2 SpEL expression 3 Let’s do it Custom annotations Define aspects 4 Permission verification First, introduce SpEL: Then, get the expression we need from the annotation. Expression parsing Custom parsing method […]

android ANativeWindow rotation rendering angle

android ANativeWindow rotation rendering angle MediaCodec rotation angle reference videoExtractor opens an angled video file mediaFormat.getInteger(MediaFormat.KEY_ROTATION); gets the angle MediaFormat mediaFormat = videoExtractor.getTrackFormat(j); String mime = mediaFormat.getString(MediaFormat.KEY_MIME); if (mime.startsWith(KEY_VIDEO)) {//Match the track corresponding to the video videoExtractor.selectTrack(j);//Select the track corresponding to the video long duration = mediaFormat.getLong(MediaFormat.KEY_DURATION); int width = mediaFormat.getInteger(MediaFormat.KEY_WIDTH); int height = mediaFormat.getInteger(MediaFormat.KEY_HEIGHT); […]

SpringBoot integrates Dubbo and Nacos

1. Overview Dubbo is a high-performance, lightweight open source distributed service framework, which was early open sourced by Alibaba. It provides distributed service management functions such as service registration, discovery, invocation and load balancing, which provides great convenience for distributed development. The core concepts of dubbo include: Provider (consumer provider), Consumer (service consumer), Registry (registration […]

Spring-boot Mybatis-plus practical application

Article directory Preface 1. springBoot integrates mybatis-plus 1.1 maven introduces dependencies: 1.2 Configure data source:: 2. Use: 2.1 mysql prints the executed sql settings: 2.2 Paging query: 2.3 Conditional constructor: 2.3.1 QueryWrapper query: 2.3.2 UpdateWrapper update: 2.3.3 LambdaQueryWrapper query: 2.3. LambdaUpdateWrapper update: 3. Use of plug-ins: 3.1 Custom ID generation: 3.2 Logical deletion: 3.3 Autofill: […]

Stop writing tool classes by yourself, Spring Boot has all the built-in tool classes you need! !

Assertion An assertion is a logical judgment that checks for something that shouldn’t happen The Assert keyword was introduced in JDK1.4 and can be turned on through the JVM parameter -enableassertions SpringBoot provides the Assert assertion tool class, which is usually used for data validity checking. //Requires parameter object to be non-null (Not Null), otherwise […]

Clustering algorithm–K-Means algorithm

cluster learning 1. Clustering concept: 1. Unsupervised problem: We have no labels in our hands, and the computer needs to learn the labels by itself. 2. Clustering: In a pile of data, similar things are grouped into a group, and a group is a category, also called a cluster. 3. Difficulty: How to evaluate the […]