Overview If the API interface docked with the front-end is captured by a third party and maliciously tampered with the parameters, it may cause data leakage or even tamper with the data. I mainly focus on the three parts of timestamp, token, and signature to ensure the security of the API interface. 1. After the user successfully logs… Read More »
I. Introduction A process is a running activity of a program with independent functions on a certain set of data. In other words, when the system schedules multiple CPUs, the basic unit of a program. Process is not an unfamiliar concept to most languages, as the world’s best language PHP" is certainly an exception. 2. Environment The… Read More »
Array Array deduplication Find the largest array Find the smallest array Returns the original array divided by an array whose size is the length Check the number of occurrences of an element in the array Flatten array Default depth expand all Compare two arrays and return the different elements Return the same elements in two arrays Delete… Read More »
This post will summarize 8 component communication mechanisms in Vue.Js. The daily development of component communication is close, and familiarity with component communication can better develop business. Vue.js Passing values between components 1. The parent component passes the value to the child component Generally, this involves the following procedures: Introduce child components in parent components Register subcomponents… Read More »
Q11: Discuss HashMap resizing in JDK 1.8 When putting an item, if the map finds that the current bucket occupancy has exceeded the proportion specified by the Load Factor, then a resize will occur. The resizing process simply means expanding the bucket to twice its original size, then recalculating the index and putting the nodes in the new… Read More »
Q6. How to specify the initial value of the Hashmap in JDK 1.8? Simply use the following declaration. Q7. How to ensure the initial value is 2 to the power of n? In order to ensure the initial value is 2 to the power of n, we have to leverage an algorithm that first finds the bit with… Read More »
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 »
Q1. Please breifly discuss Hashmap in JDK 1.8 Hashmap is a map interface based on hash table implementation. This implementation provides all optional mapping operations and allows empty values (value) and empty keys (key). (The HashMap class is roughly equivalent to Hashtable, but it is thread-unsafe and allows null values) This class cannot guarantee the order of mapping;… Read More »
In our daily development, we may casually expose the database password directly in plaintext in the configuration file, which can be done in the development environment, but it is not recommended to do so in the production environment. After all, security is not trivial. No one knows which day the password is somehow leaked. Today we will talk… Read More »
You may want to prevent the user of your web application from debugging your website. Specifically, the user should not access browser developer tools by pressing F12 or Ctrl+Shift+J or by clicking on the customize and control > more tools > developer tools. To accomplish this, you can use the following ready-to-use JavaScript code. Method 1: Only when… Read More »
Go 1.16 contains many Modules-related updates, and you can directly view its Release Note for details. Overall, it contains the following points: Go111module is On by default. If you want to restore the previous behavior, you need to set Go111module to Auto, which almost means that the GOPATH mode will gradually fade out of people’s vision; The go… Read More »
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 »
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 »
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 »
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 »
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 »
Queue-based and message-based TTL TTL is short for time to live, as the name implies refers to the time to live of the message. rabbitMq can set the message expiration time from two dimensions, namely the queue and the message itself.Queue message expiration time-Per-Queue Message TTL:Set the x-message-ttl parameter of the queue to set the message’s survival time… Read More »
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 »
Heap Java’s heap is a runtime data area, and objects of classes allocate space from the heap. These objects are created by instructions such as new and destroyed by the garbage collector. The advantage of the heap is that it can allocate memory space dynamically. It is unnecessary to tell the compiler how much memory space is needed… Read More »
We can create a simple heartbeat animation using HTML and CSS without much coding. The only thing we need to do is to add a box and use CSS to display it. First, add a visual box to the page Then, make a heart-shape box Finally, set up the animation. It’s worth noticing that the animation must be… Read More »