Getting Started with ActiveMQ 5

This article mainly records the configuration and writing process of ActiveMQ from installation to application to the project. You quickly configure the application following this post. You can download ActiveMQ from its official website. Modify the configuration First, find the activemq.xml file in the config directory. Then, find the <policyEntries> tag, add the following configuration under the tag… Read More »

Best practices of developing SpringCloud-based microservices

Nowadays, SpringCloud-based microservice development is becoming more and more popular, and various open-source projects on the Internet are emerging endlessly. We can refer to open source projects to implement many out-of-the-box functions in actual work, but we must abide by certain conventions and specifications. This post combines some of the problems encountered in our actual development to sort… Read More »

Pika Cluster Horizontal Scaling: Unlimited Performance

Background Pika is a persistent large-capacity redis storage service, compatible with most of the interfaces of string, hash, list, zset, and set (compatibility details), and solves the capacity bottleneck of redis that is insufficient due to the huge amount of stored data. Users can migrate from redis to pika service without modifying any code. It has good compatibility… Read More »

SOLID principles: Introduction, Best Practices, and Interview Questions and answers

SOLID principle introduction Following practical and clear design principles is conducive to flexible and reliable software design. SOLID is an acronym for the five essential principles of object-oriented design. When we design classes and modules, following the SOLID principles can make the software more robust and stable. Q1: What are the SOLID principles? S – Single responsibility principle… Read More »

Use R2DBC with MySQL database

Introduction R2DBC is an asynchronous, non-blocking relational database connection specification. Although some NoSQL database vendors provide reactive database clients for their databases, for most projects, migrating to NoSQL is not an ideal choice. This prompted the birth of a universal, responsive relational database connection specification. As a relational database with a huge user base, MySQL also has a… Read More »

Best practices of implementing pagination for one-to-many results in SQL

Introduction One-to-many results paging is a prevalent scenario, for example, we want to query the product and product picture information. But many people will encounter the misunderstanding of paging here and get incorrect results. Come to analyze and solve this problem today. Problem analysis Let’s first create a simple commodity table and the corresponding commodity picture relationship table.… Read More »

How to avoid double payments and ensure idempotency in a distributed web application with Spring Boot

Idempotency Idempotency means that no matter how many times you execute the request, the result is the same. Speaking of idempotency, you have to say repeated submission. You click the submit button continuously. In theory, this is the same piece of data. The database should only store one item but store multiple items, which violates idempotency. Therefore, we… Read More »

How to set up a cron job in Django using django-crontab

Why do we use scheduled tasks For the static homepage, considering that the data of the page may be maintained by multiple operating personnel and changes frequently, it is made into a scheduled task, that is, the static is performed regularly Performing scheduled tasks in Django can be achieved through the django-crontab extension. Installation Configure installed applications Add… Read More »

Configuring HugePages on Linux

In virtual paging storage, the virtual storage space and physical main storage space are divided into pages of fixed size, and the memory allocation for threads is also in units of pages. For example, if the page size is 4K, 4GB/4KB=1M records are needed for 4GB storage space, that is, there are more than 1 million 4KB pages.… Read More »

TOP 10 JVM Garbage Collection Interview Questions

Questions: Describe the Java garbage collection mechanism. What is GC? Why do we use GC? Advantages and principles of garbage collection, and describe two recovery mechanisms. What is the basic principle of the garbage collector? Can the garbage collector reclaim memory immediately? What’s the way to actively notify the virtual machine for garbage collection? What are the reference… Read More »