SEARCH KEYWORD -- EVENT MECHANISM

  How to check whether a struct implements an interface in GoLang

Unlike other programming languages like Java, when implementing an interface in GoLang, there is no syntax like below to explicit tell the relationship: type I interface { } type A struct implements I { } When looking at the code or running the code in GoLang, it might lead to a case one doesn't know whether a struct implements interface before trying to use it as some interface. According to GoLang spec, as long as a struct implements all functions of an interface, it is considered as having i...

   GOLANG,INTERFACE,IMPLEMENTATION,CHECK     2020-05-03 00:05:54

  XMLHttpRequest Level 2 user guide

XMLHttpRequest is a web browser interface, it makes it possible for JavaScript doing HTTP(s) communication. Microsoft's IE5 first introduced XMLHttpRequest, because it's so useful that many other browsers also adopted this. AJAX came to the front since. However, this interface is not standardized, implementation among different browsers is different, with the emerging of HTML5, W3C is considering to standardize this interface. In February 2008, they proposed a XMLHttpRequest Level 2 draft. This ...

   XMLHttpRequest, progress, upload, binary data     2012-09-19 11:51:50

  Supervisord, God and Monit, which one to choose?

With the popularity of Docker, more and more service have been moved into docker containers and they are easy to build up and maintain for each atomic service(though it's a bit complex to maintain multiple docker containers which contain different service to form a complete solution). Ideally, each docker container should only contain one service which has only one running process. However, in reality there would be cases multiple processes would run in one single docker container and there is a...

   DEVOPS,MONIT,SUPERVISORD,GOD,DOCKER     2017-11-25 12:28:11

  Why is single threaded Redis so fast

Redis is a high-performance, in-memory key-value database. According to official test reports, it can support around 100,000 QPS (queries per second) on a single machine. However, Redis uses a single-threaded architecture in its design. Why does Redis still have such high performance with a single-threaded design? Wouldn't it be better to use multiple threads for concurrent request processing? In this article, let's explore why Redis has a single-threaded architecture and still maintains its spe...

   REDIS,SINGLE-THREADED,MULTI-THREADING     2023-02-28 05:16:22

  File upload once again

File upload is one of the oldest operation of web design. After 20 years, it's still has no big change, difficult to handle, lack of interaction and poor user experience. Web developers have thought many methods to improve the experience of uploading file in web apps, they developed various plugins based on different JavaScript libraries. However, because of the difference among different web browsers, there is no common interface which makes these plugins work properly or easily on all web brow...

   Web design, File upload, Asynchronous,HTML5     2012-09-02 11:52:21

  Solution to getKeyCode() returns 0 in Java

The getKeyChar method always returns a valid Unicode character or CHAR_UNDEFINED. Character input is reported by KEY_TYPED events: KEY_PRESSED and KEY_RELEASED events are not necessarily associated with character input. Therefore, the result of the getKeyChar method is guaranteed to be meaningful only for KEY_TYPED events.For key pressed and key released events, the getKeyCode method returns the event's keyCode. For key typed events, the getKeyCode method always returns VK_UNDEFINED....

   Java,KeyCode,0,KeyListener     2011-06-06 10:38:11

  Best practices of front end optimization

1. Use DocumentFragment or innerHTML to replace complex elements insertion DOM operation on browser is expensive. Although browser performance is improved much, multiple DOM elements insertion is still expensive and will affect the page load speed. Assume we have an ul element on our page, we now want to retrieve a JSON list using AJAX and then update the ul using JavaScript. Usually we may write it as : var list = document.querySelector('ul'); ajaxResult.items.forEach(function(item) { // ...

   JavaScript,Front end,Optimization,Tips     2013-07-06 11:26:27

  CSS box-shadow Can Slow Down Scrolling

Working on one of the Chromebooks Google lets you borrow on Virgin America flights, I noticed scrolling down the page on my airbnb.com dashboard was much slower than on my normal laptop. I chalked it up to weak Chromebook hardware, but other sites were scrolling just fine. box-shadow had caused slow scrolling on our search results page before, so I did some investigation.I used Chrome's Timeline tab to see the duration of paint events on the page. Before each test I forced a garbage collection a...

   CSS,box-shadow,performance,Timeline,Chromebook     2011-11-13 08:13:48

  Introduction to DTLS(Datagram Transport Layer Security)

Secure communication has become a vital requirement on the Internet. Lots of information transferred through the Internet are sensitive data such as financial transactions, medical information, media streaming etc. To ensure security of data transferred on the Internet, a few secure protocols have been designed including SSL/TLS and IPsec. Many large websites in the world have adopted TLS. Apart from SSL/TLS, there is some other protocol designed to be used in special cases. One of them is ...

   JAVA 9,DTLS,TLS,SECURITY     2016-04-02 05:55:36

  Modal dialog in Java example code

In Java, we can create modal dialog so that the main JFrame cannot be operated on until the modal dialog is closed. To achieve this, we need to use one class in Java--JDialog. This class can be used to create an modal dialog.Example code : import javax.swing.JDialog; import javax.swing.JLabel; import javax.swing.JPanel; public class Dialog extends JDialog{ public Dialog(){ super(); JPanel panel=new JPanel(); panel.add(new JLabel("Hello dialog")); this.getCont...

   Java,Modal,JFrame,JDialog,Demo,Code     2011-08-18 09:50:27

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