SEARCH KEYWORD -- Change


  PHP advisory file lock : flock

When we process a file in PHP, we may often need to acquire a lock so that other scripts cannot edit the same file at the same time. There is a flock() function in PHP which can help us lock the file we want to process. But there is one issue we should take care. Recently, ffb encountered one issue while he was trying to lock a file handle. The codes are below: $filename = "/tmp/lock.txt";      $fp = fopen($filename, "r+");   if (!$fp...

   flock(),advisory locking,PHP     2013-04-23 11:42:48

  Basic Mistakes Developers Make When Creating APIs

Today, there are many tools that developers can use to create an API, meaning that some of them can come up with an API within a matter of minutes. However, there is a vast difference between just creating an API and building one that meets all your expectations, is reliable and secure. Some developers create APIs that work well but forget some basic things that, within no time, bring a lot of issues to the API users. In this article, we are going to talk about the basic mistakes that developers...

   API,API DESIGN,RESTFUL API     2020-08-19 07:54:03

  iWatch is coming to us before 2014

There are a variety of rumors around Apple iWatch. But according to Bloomberg,  Apple's smart watch is expected to be on sale at the end of this year.It is reported that iWatch might have phone and location tracking capabilities, it will also have a built-in pedometer and some health monitoring sensors. Previously Apple supplier and Gorilla Glass manufacturer Corning said that iWatch would be available only after at least 3 years. But recently Apple retained some iWatch related patents, it...

   iWatch,Apple,Google Glass     2013-03-04 18:09:42

  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

  Solve Hibernate "Too many connections" issue in MySQL

When working with Hibernate and MySQL, sometimes some exceptions will be thrown after sometime. The exception may seem like : java.sql.SQLException: Data source rejected establishment of connection, message from server: "Too many connections" This means there are too many active connections on the MySQL, you can use SHOW STATUS LIKE '%Threads_connected%'; to check the active connections to MySQL. If you want to change the maximum connections allowed to MySQL. You can execute: set global max_co...

   MySQL,Hibernate,Clos     2013-09-04 22:20:49

  Why localStorage only allows to store string values

localStorage allows data to be stored in browsers across sessions, the data will be there even though the session is expired. It is frequently used to store static data so that they can be loaded when needed. But as per spec, it says that the keys and the values are always strings (note that, as with objects, integer keys will be automatically converted to strings). Why cannot store the object as it is? Take a look at an example: var str = "test"; localStorage.setItem("str", str); cons...

   JAVASCRIPT,LOCALSTORAGE     2020-04-05 00:54:29

  How does Class box get 1 million users with only 4 people?

"Class box" is an app which helps students create course plan developed by 4 Chinese. This app was created in 2012. They get over 1 million users with only 4 people. How do they make this? The co-founder of "Class box" Tianfang Li explains this on Zhihu. Here is what he said: About millions of users, in the mobile Internet era what we need to do is just find a good entry point, rapid iteration and with a little luck, a small team or even an independent developer can make millions user level prod...

   class box,team size,sillicon valley     2013-04-03 08:08:21

  Things to Look for in Microsoft .NET Framework 4.7

The .NET Framework 4.7 is the updated version of the .NET Framework 4.6.2.  It can run along with earlier versions of the .NET Framework. On installation it appears as an update for Microsoft Windows under the Installed Updates item in Control Panel. The improvements in the.NET Framework 4.7 includes: High DPI support for Windows Forms applications on Windows 10 Touch support for WPF applications on Windows 10 Enhanced cryptography support Performance improvements .NET Framework Documenta...

   ASP.NET, ASP.NET FRAMEWORK     2017-07-18 05:55:20

  Yahoo to change name to Altaba and becomes Alibaba's father

Yahoo, one of the most successful Internet giants in later 1990s, is now becoming a company living with selling assets(offices, domain names) and holding the stocks from Alibaba. Its core business which it was proud of has been sold to Verison with $4.8 billion as disclosed in some document submitted to SEC. Now it's starting the process of changing its name to Altaba. After the acquisition, the current Yahoo CEO Marissa Mayer will resign from the board. But the company will still keep some val...

   YAHOO,FATHER,ALIBABA,ALTABA,CHINA,NEWS     2017-01-15 04:07:24

  Convert ext3 to ext4 file system on CentOS

ext3 is a journaled file system that is commonly used by the Linux kernel. It is the default file system for many popular Linux distributions, including Debian. Stephen Tweedie. On June 28, 2006, Theodore Ts'o, the principal developer of ext3, announced an enhanced version, called ext4. Today, we will show how to convert ext3 to ext4 format on CentOS. System environment: Release version : CentOS release 5.4(Final) Kernel:  Linux localhost.lo...

   CentOS, ext3 to ext4     2012-11-21 11:40:45

RECENT