SEARCH KEYWORD -- Code Jam 2013



  JavaScript tips both novice and veteran developers can benefit from

In this post, we will share some less known but powerful JavaScript tips which can benefit both novice and veteran JavaScript developers. 1. Truncate array with array length We all know that object are passed by reference in JavaScript, but we may be bitten by this rule. Please check below example: var arr1 = arr2 = [1, 2, 3]; //Change arr1 arr1 = []; // arr2 will still be [1,2,3] arr1 and arr2 point to the same array [1,2,3] initially, later when arr1 repoints to [], the reference to arr2 is n...

   JavaScript,Array,push     2013-08-21 04:09:10

  Tips for a better first-time hackathon experience

Here are a few things you can consider. These are by no means the only way to go about hackathons, just what's worked for me.ProjectI strongly strongly recommend doing something you haven't done before. Even if you're going into a hackathon with the intention of winning, trying something new is always fun and will keep you engaged throughout the event. Jump into mobile development, try hardware hacking, write a compiler, whatever; it's always fun to try out new things.Sticking to things you're c...

   hackathon     2014-03-31 07:25:09

  Java 9 release is delayed again

The original Java 9 planned release date is March 2017. But latest source shows that Java 9 release will be delayed again to July 2017. It's four months later than the planned date. Oracle Chief Architect of Java Platform group Mark Reinhold proposes this new release date in a message sent on the OpenJDK mailing list.  Despite this progress, at this point it's clear that Jigsaw needs more time. We recently received critical feedback that motivated a redesign of the module ...

   JAVA,RELEASE DATE,JAVA 9,JAVA 9 DELAY     2016-09-26 12:22:53

  MaxHeapSize in JVM

MaxHeapSize is an option which is to set the JVM maximum heap size can be allocated. We can specify the MaxHeapSize as VM argument when we run the program by setting -XX:MaxHeapSize=, here can be 2M, 20M, 200M etc. We can also view the current MaxHeapSize set by setting different JVM options. To view the MaxHeapSize, we can use two JVM options : -XX:+PrintFlagsFinal and -XX:+PrintCommandLineFlags. Below is one example when running -XX:+PrintFlagsFinal: bool MaxFDLimit ...

   JVM,MaxHeapSize,Alignment     2014-06-17 07:01:50

  A Python assignment trap

Python has no assignment, it only has reference. Assume, we have following code snippet: >>> values = [0, 1, 2] >>> values[1] = values >>> values [0, [...], 2] Why the result is not [0, [0, 1, 2], 2], instead it goes into an infinite loop? To understand this, we need to understand some basics about Python. Python has no variables, it only has labels. When we run: values = [0, 1, 2] Python will first create a list object [0,1,2], then it labels it as values. If we later...

   Python,Assignment,Trap,Shallow copy     2013-07-19 22:08:36

  Eight C++ programming mistakes the compiler won’t catch

C++ is a complex language, full of subtle traps for the unwary. There is an almost infinite number of ways to screw things up. Fortunately, modern compilers are pretty good at detecting a large number of these cases and notifying the programmer via compile errors or warnings. Ultimately, any error that is compiler-detectable becomes a non-issue if properly handled, as it will be caught and fixed before the program leaves development. At worst, a compiler-detectable error results in los...

   C++,Compiler,Error detection     2012-04-08 09:55:20

  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

  OT Railway System Development: How to Use PLC to Implement Land Based Railway Track Fixed Block Sign

Figure-00: Railway fixed block signaling system over view diagram, version v1.3 (2024) Project Design Purpose: This project aims to use Programmable Logic Controllers (PLC) with train detection sensors and train control signals to develop an automated OT system for railway track fixed block signaling control. The system will include a digital equivalent simulation to explain the logic of the track fixed block Automatic Train Control (ATC) mechanism for demonstration and training purposes. In th...

       2024-07-27 04:08:41

  2D Indoor CQB Robot Simulation

Program Design Purpose: The integration of robots in Close Quarters Battle (CQB) represents a significant advancement in modern military and law enforcement tactics. These robots, designed to navigate tight spaces, gather real-time intelligence, and engage threats, are invaluable assets in high-stakes scenarios. Our goal is to develop a 2D tactical board simulation system, similar to a computer game, that can load building floor blueprints, display CQB squad (robot) positions, enemy locations, ...

       2024-08-11 08:40:31

  A HTTPS client and HTTPS server demo in Java

In this post, I will create a HTTPS server and HTTPS client demo which can establish HTTPS communication between a server and a client using Java. This should be very useful when we want to test our understanding about SSL communication. We will use both a detailed SSL client and a simple HttpsURLConnection as the HTTPS client. Before creating the actual HTTPS server and HTTPS client, we first need to generate the keystore and truststore to be used by the server and client. To generate the keyst...

   SSL,HTTPS,JAVA,DEMO     2015-10-23 09:04:36