Programming VIP

  Foreword This is the third day of my participation in the revision challenge in November. See the activity details: the last revision challenge in 2021. Are you still encapsulating tool classes and tool methods in the project? Let Hutool help you. It is a friendly alternative to the util package in the project, covering all aspects of ...

Linear algebra and code implementation (I) vector background The Linear Algebra I studied in university is a little forgotten now, and I am not proficient in the code implementation; This column mainly reviews the basis of linear algebra and implements the code part; 1. Some basic concepts Essence: the basic expression of a group of numbers ...

Link: https://juejin.im/post/6869953788388573192 Get ServiceManager from Java layer In the previous article, I went to the getIServiceManager() method to get the ServiceManager object. getIServiceManager() //frameworks/base/core/java/android/os/ServiceManager.java private static IServiceManager getIServiceManager() { if (sServiceManager ...

In Linux, have you ever naively thought that if you delete a file with rm, the occupied space will be released? Things may not always be what you want. Generates a random content file of a specified size Let's take a look at the current space size of each mounted Directory: $ df -h /dev/sda11 454M 280M 147M 66% /boot I selected ...

1, Introduction In the previous article[ springboot: those pits that use asynchronous annotation @ Async >The incorrect usage of using @ Async annotation to obtain task execution results is introduced in. Today, let's share another common error. 2, Code demonstration Here is the code of my controller, package com.atssg.controller; impor ...

The CAS operation process mentioned above is not very difficult. But the above description is not enough. Next, I will introduce some other background knowledge. With these background knowledge, we can better understand the follow-up content. 2. Background introduction As we all know, CPU transmits data through bus and memory. In the multi- ...

//Use the thread pool to perform a task executor.execute(() -> { // Do something }); //Closing the thread pool will prevent the submission of new tasks, but it will not affect the submitted tasks executor.shutdown(); //Close the thread pool, prevent new task submission, and interrupt the currently running thread executor.showdownNow( ...

development tool Python version: 3.6 four Related modules: pygame module; And some Python built-in modules. Environment construction Install Python and add it to the environment variable. pip can install the relevant modules required. Principle introduction I don't need to introduce the rules of the snake game, T_T. Writing a snake gam ...

Semaphore is a count based semaphore. It can set a threshold. Based on this, multiple threads compete to obtain the license signal and return it after making their own application. When the threshold is exceeded, the thread application license signal will be blocked. Semaphore can be used to build some object pools and resource pools, such as ...

[]( )Callable thread creation public class CallableTest { public static void main(String[] args) throws ExecutionException,InterruptedException { // new Thread(new Runnable()).start(); // new Thread(new FutureTask<V>()).start(); // new Thread(new FutureTask<V>( Callable )).start(); new Thread ...