Programming VIP

Arthas is an open source Java diagnostic tool for Alibaba and is loved by developers. Github: https://github.com/alibaba/arthas File: https://alibaba.github.io/arthas Arthas 3.1.2 continues to add new features, highlighted below: logger/heapdump/vmoption/stop command Connect arthas from different networks via tunnel server for easy unif ...

In Linux, the use of deleting rm commands should be cautious. Sometimes important files are deleted due to misoperation. At this time, don't be too nervous. If you operate properly, you can still recover. EXT Type File Recovery Deleting a file does not actually clear the inode node and block data, but deletes the name of the file in the block ...

First look at a chestnut EXPLAIN select * from employees where name > 'a'; If using name index to find data needs to traverse the name field joint index tree, and then according to the traversed primary key value to the primary key index tree to find the final data, the cost is higher than the full table scan. Overlay index optimization c ...

A master once said that he knows the database he manages as well as his wife. Personally, he thinks it contains two aspects of understanding: 1. At the level of stability, more attention is paid to high-level measures such as high availability, separation of reading and writing, load balancing, disaster preparedness management and so on. 2. A ...

1. What is Policy Gradients The basic idea of a strategic gradient is to output the probability of an action or action directly according to its state.So how to output, the simplest is to use a neural network. When we use a neural network to enter the current state, the network can output the probability of each action we take in this state. ...

Differences between Session landing and Token landing 1. Session login is to generate user-related session data on the server side and send the session_id to the client side to store in cookies, so that when the client requests, session_id can verify the existence of session data on the server side, so as to complete user authentication. This a ...

spring Basic Components as shown above: spring configuration file First use the xml configuration file, then turn to annotations. //Configuration class ==== configuration file @Configuration public class MainConfig { //Register a bean in the container with the type of the return value. //Note that the @Bean registered bean, which defa ...

View and control processes The relationship between programs and processes program Executable code and data stored on media such as hard disks, discs, etc. Statically saved code process Program code running in CPU and memory Code executed dynamically Parent and Child Processes Each process can create one or more processes Simply put, ...

Catalog Java implements email function Preface development environment Code Effect Concluding remarks Java implements email function Preface The application scenarios of e-mail are very extensive, such as new users joining, sending preferential lists instantly, retrieving ...

Then the last article (using session to save user data) let jwt to save user data.Passport-jwt/json webtoken is used here.passport-jwt is a validation strategy of passport. It is validated using JWT (json web token).JSON webtoken is a module for encoding, decoding and verifying jwt. Using jwt to save user data and using session to save user dat ...