Today's Question:  What does your personal desk look like?        GIVE A SHOUT

SEARCH KEYWORD -- Data structure alignment



  Should we use Abstract class or Interface?

When we write programs, we may often get into a situation where we don't know whether we should use Abstract class or Interface when we want to define an abstract object. These two are very similar and they are interchangeable in many cases. On Stackoverflow, this question is asked lots of times and it's related to many programming languages. Also in the official documentation of PHP regarding the Abstract class and Interface, people are arguing about this. To understand this question, their dif...

   DIFFERENCE,INTERFACE,ABSTRACT CLASS,COMPARISON,OOP     2013-04-15 11:44:36

  First Chinese app on Google Glass : PM25.in

PM25.in is an open source PM2.5 project developed by BestApp. It retrieves PM2.5 data of different cities in China through a crawler and then processes the data retrieved. They also created an API which enables third parties to access these data. Now the team has built something new, they moved this project to Google Glass and developed the world's first Chinese Google Glass application -- PM25.in. Now users with Google Glass can check PM2.5 of different cities in China. The final effect on Goog...

   Google Glass,China,PM25.in,BestApp     2013-06-23 10:17:40

  What and what not to log while debugging

Log is a critical part of an application. It serves as an eye to the programmer on how the application is working while debugging. Especially for applications running on production environment, if the application encounters problem and the problem cannot be reproduced on other environments, log will be extremely useful. While log is essential, but developers have to log smartly. Because if don't put log smartly, you may not get what you want while debugging or you may get too many...

   PROGRAMMING,DEBUG,LOG,SUPPORT     2016-03-14 08:09:03

  PHP to get long running process progress dynamically

Frequently in web applications, we may have a request to the back end system which may trigger a long running process such as searching huge amount of data or a long running database process. Then the front end webpage may hang and wait for the process to be finished. During this process, if we can provide the user some information about the progress of the back end process, it may improve user experience. Unfortunately, in web applications, this seems not an easy task because web scripting lang...

   AJAX,PHP,progress,long process,demo     2012-06-04 07:29:37

  What does session_destroy() do in PHP?

In PHP manual, the description for session_destroy() function is : session_destroy() destroys all of the data associated with the current session. It does not unset any of the global variables associated with the session, or unset the session cookie. To use the session variables again, session_start() has to be called. I am confused about this description. If this function destroys all session data, then why the global variables associated with the session are not unset? Why can we u...

   session_destroy,session_start     2013-08-31 09:59:05

  ByteBuffer in Java

ByteBuffer is introduced in java.nio since Java 1.4. It provides a way of representing raw structured data such as from a file or from network. It enables fast access of underlying data compared to traditional ways like byte[] Prior to Java 1.4, if you want to represent a structured raw data, you need to create a byte[] and then having a set of checks to delimit the byte array to get the expected tokens. There are three ways to create a ByteBuffer: Wrapping an exiting array by calling ByteBuffe...

   JAVA,BYTEBUFFER,ALLOCATION     2015-07-08 03:17:44

  HTML5 photo taking and uploading app implementation

Underthe support of HTML5 standard, Building Web App to take photos is now possible.I will elaborate on how to take photos using Web App, display them on the pageand upload them to the server. 1.     Videostream HTML5 TheMedia Capture API provides the programmable  access to video camera on phones, users canuse the getUserMedia() method to get the video stream provided by video camera.What we need to do is to add a HTML <video> tag and make the videostrea...

   HTML5,Photo taking,Media Capture API ,Implementation     2012-03-15 07:19:49

  Why exception would be thrown when deleting element while looping through HashMap in Java

HashMap and other Collection types are frequently used in Java application programming. This post will explain why exception would be thrown when deleting element with Map.remove() while looping through a Map using Iterator. This issue would also occur to other Collection types such as Set, List. Below is a sample code snippet demonstrating the exception thrown. Map<String,String> map = Collections.synchronizedMap(new TreeMap<String,String>()); map.put("key1","value1"); map.put("ke...

   JAVA,HASHMAP,CONCURRENTMODIFICATIONEXCEPTION     2018-06-30 12:49:09

  Use of @font-face

Almost all web browsers(including the dinosaur browser IE6) support the web font property @font-face. Its usage is: @font-face { font-family: 'MyWebFont'; src: url('webfont.eot'); /* IE9 Compat Modes */ src: url('webfont.eot?#iefix') format('embedded-opentype'), /* IE6-IE8 */ url('webfont.woff') format('woff'), /* Modern Browsers */ url('webfont.ttf') format('truetype'), /* Safari, Android, iOS */ url('webfont.svg#svgFontName') format('svg'); /* Legacy iOS */ } Now we...

   CSS,@font-face     2014-06-08 07:17:34

  8 Step Guide to Rewrite Articles

Crafting an eye-catching article may be god-gifted talent, for many people. But anyone can learn the skill of article rewriting. You can find articles all around, newspapers, websites, and magazine even at the back of different products. These articles will give a basic understanding of what readers look into articles and what they expect. It will help you to craft an appealing article according to readers demand. For beginners, below you will find a list of four types of articles. Description...

   ARTICLE WRITE,TOOL     2019-05-15 07:58:52