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  A simple tutorial on writing Java native program

Java provides Java Native Interface(JNI) to enable developers to write programs which can utilize the underlying native libraries of the operating system. The benefits of writing native code are that they normally provide better performance compared to Java codes. Sometimes if you want to utilize some system specific functions you may also want to use JNI. One main drawback of writing native code is that your application may not be platform independent anymore. This is not what Java is desi...

   Java native interface, JNI, Native code, Sample     2015-08-15 08:28:15

  When can Chinese buy fresh food online?

Farmigo is an online agricultural marketing platform. Farmers can post their own products, people can directly purchase their favorite ingredients on it. Farmigo promises that fresh ingredients will be sent to the designated location within 48 hours, but the price is 20-30% cheaper than the supermarket.In other words, Farmigo itself does not sell agricultural products, it just plays a platform intermediary role. Their advantages to attract consumers are fresh ingredients supply, home delivery a...

   Agriculture, Online sales, B2B     2012-12-12 13:37:03

  An experience of fixing a memory-corruption bug

During the last 4 months, I was disturbed by a memory-corruption bug, and this bug will cause program crash. Until last Monday, I found the root cause and fixed it. This debug process is a difficult but memorable experience, so I will share it in this article.   My program works as a SMS Hub. When it receives a SMS, it will allocate a structure in heap memory like this: typedef struct { ...... int *a[8]; ...... } info; After processing the SMS, the program will free the m...

   c, debug, unix, solaris, multi-thread     2014-05-04 03:52:43

  Some laws of interactive design

The well known quote from Alan Cooper is   Conforming to the standard unless there is a better choice. There are some best practices in interaction design. How many do you know? 1. Fitts' Law The time from one start point to target point is determined by two parameters: The distance to the target and the size of the target. )D and W in above picture), the formula is : T=a+blog2(D/W+1). It was first proposed by Paul Fitts, it is mathematical model used to predict the time from any poin...

   interaction design, laws, Fitts' law     2012-11-16 11:25:24

  Create temp file in Bash using mktemp and trap

When working on Linux Bash, sometimes there is need to create temporary file. A common way of creating temp file on Linux is creating some file in /tmp directory. However there is security risk when creating temp file in /tmp directory. This post will show how to securely create temp file in Linux Bash. When creating file in /tmp directory, there are some security risks. This directory can be accessed by any user on the system, any user can write data into this directory as well. The files creat...

   LINUX,MKTEMP,TRAP,TEMP FILE     2019-12-30 23:28:23

  Additional steps need to implement to setup shadow-boxV2 OPTEE on Raspberry PI

We followed the Shadow-box v2 project from the https://github.com/kkamagui/shadow-box-for-arm to set up the trustZone on Raspberry PI modeB to protect the Linux Kernel. But got a problem when doing the step: [3.6.5. Activate Shadow-Box for ARM and Start Secure Pi!] to create the hash for the memory area. The result is not shown. If you met the same problem, this is what I did to fix the problem on my PI: 1.1  When we do the step [3.5.1. Copy OP-TEE OS with Shadow-Box for ARM and N...

   HARDWARE,RASPBERRY PI     2019-05-20 08:52:55

  GitHub : Code is the most direct way for programmers to communicate

If not invested by Andreessen Horowitz, GitHub might not be noticed by Forbes, CNN, New York Times. People didn't know this tool because it was very far away from the world -- GitHub is a project hosting service used by programmers.But to some programmers, it is not just a place for project hosting, it is`also the hub for open source projects, a place for programmers improving themselves and a social network for programmers.There are around 3.26 million projects hosted on GitHub currently, inclu...

   GitHub,Open source,Hosting,Social     2012-07-20 11:38:31

  Microsoft: Apple UI sucks, Metro UI is philosophy

Microsoft is a typical IT company of the last century - a huge strength, but turned a little less sensitive. Now, Microsoft is trying to change the tradition of no connection between home desktop and mobile system developers, the best indicator of this effort is their design.Microsoft products, especially software products, are now gradually using a simple, plain and neat appearance: Metro. But if you think the Metro is just on Windows 8, Windows Phone, the application market and Xbox Live,...

   Windows, Metro UI,Apple     2012-04-13 07:12:21

  Handy PHP functions should be in your toolkit

When developing projects, there are always some common work should be accomplished, for example, encrption/decryption, get IP. As a PHP developer, you should have a list of the handy functions in your toolkit so that you can pick up in every project you work on. Here is a summary of some handy PHP functions. 1. PHP encryption/decryption Encryption/decryption can be used when storing user confidential information such as passwords. Below function uses base64 and MD5 to accomplish encryption/decry...

   PHP,function,real IP,SQL injection     2014-12-06 08:46:08

  Essay Writing - Time Management For Students

Most of the senior year students have a billion things to do. You have to attend classes every day, participate in after school activities, do home assignments, sports, and do a part-time job. And now you have to deal with a new essay. So, you have to focus on time management which will help you accomplish the writing project faster and will bring some balance in your life.  Many students do not find time to write a college essay and this makes them searching who help. If you ask yourself ...

   STUDENT,ESSAY,TRAVEL     2020-01-23 07:45:11

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