Ujjwal's Blog

JEP 254: Compact Strings

2016-02-26T04:41:00.000-08:00

JEP 254 proposes changing the internal representation of strings inside the JVM. As most readers surely know, strings are stored using UTF-16, which uses two bytes per character. This proposal suggests using a more compact, one-byte-per-character representation internally: “Data gathered from many different applications indicates that strings are a major component of heap usage and, moreover, that most String objects contain only Latin-1 characters. Such characters require only one byte of storage, hence half of the space in the internal char arrays of such String objects is going unused,” says the JEP proposal.

Changing to the more compact form would not affect existing code or any APIs; it would be a purely internal change inside the JVM and not visible to programmers. Interestingly, the information on the JEP’s web page reveals that a string compression feature was tested in Java 6. It converted String.value to an Object that pointed either to an array of 7-bit characters or an array of regular Java characters. That feature, though, was removed subsequently.

Electron - package web applications for windows/mac/linux

2015-12-10T06:48:00.000-08:00

Hello Blog Readers,

Recently i came across Electron which lets you package web applications for windows/mac/linux while also allowing you to use native platform features. Check out the link below.

http://dgit.in/ElectronPackg

Regards,
Ujjwal Soni

Firefox Os 2.5 Developer

2015-12-10T06:42:00.000-08:00

Hi Blog Readers,

Now you can try Firefox OS without needing to flash it in your Android phone, a version of OS that can be installed like any other APP.

http://dgit.in/FirefxOS

Regards,
Ujjwal Soni

Raspberry Pi Zero: the $5 computer

2015-11-26T19:44:00.002-08:00

Of all the things we do at Raspberry Pi, driving down the cost of computer hardware remains one of the most important. Even in the developed world, a programmable computer is a luxury item for a lot of people, and every extra dollar that we ask someone to spend decreases the chance that they’ll choose to get involved.

The original Raspberry Pi Model B and its successors put a programmable computer within reach of anyone with $20-35 to spend. Since 2012, millions of people have used a Raspberry Pi to get their first experience of programming, but we still meet people for whom cost remains a barrier to entry. At the start of this year, we began work on an even cheaper Raspberry Pi to help these people take the plunge.

Below is the configuration for this new Raspberry

A Broadcom BCM2835 application processor

1GHz ARM11 core (40% faster than Raspberry Pi 1)

512MB of LPDDR2 SDRAM

A micro-SD card slot

A mini-HDMI socket for 1080p60 video output

Micro-USB sockets for data and power

An unpopulated 40-pin GPIO header

Identical pinout to Model A+/B+/2B

An unpopulated composite video header

Our smallest ever form factor, at 65mm x 30mm x 5mm

Raspberry Pi Zero runs Raspbian and all your favourite applications, including Scratch, Minecraft and Sonic Pi.

Thanks,
Ujjwal

Testing tools for Angular JS

2015-11-16T20:58:00.001-08:00

Karma is a great test runner made for Angular, but can also be used with any other Javascript framework. It supports any type of testing: unit testing, midway testing and E2E testing. Karma works by opening browsers that you list in the configuration file. It then communicates with the active browser using socket.io and asks you whether to run the test or not.

Angular JS Eclipse Plugin

2015-11-16T20:51:00.002-08:00

Hi,

I'm posting this new post on my blog after long long time. Recently i was working on AngularJS, i found a great plugin for MyEclipse which works great for AngularJS. Check out the link below for more details.

https://github.com/angelozerr/angularjs-eclipse

Thanks,
Ujjwal

top-10-changes-in-asp.net-5-and-mvc-6

2015-04-21T06:22:00.000-07:00

Below link contains some of the top-10-changes-in-asp.net-5-and-mvc-6

top-10-changes-in-asp.net-5-and-mvc-6

Thanks,
Ujjwal

Convert code from C# to VB and from VB to C#

2015-04-21T06:16:00.003-07:00

Hi,

I was working on a project that needs to be converted from VB to C#, i was searching for a tool that can easily convert some part for me.

i found one http://converter.telerik.com/

Thanks,
Ujjwal

Books on Java performance tuning

2015-04-21T05:47:00.002-07:00

We usually do a performance research by writing small stop watch and it will log time taken for each business methods. You create stop watch methods something like startWath and stopWatch to start and stop a timer. The performance tuning on web applications vary from server to server since there are some server level tuning also improves your application's performance.

Below are some books which might help you.

Java Performance: The Definitive Guide is a really good book and its quite latest as well - covers G1 GC in depth.

Then there is another book: Java Performance by Charlie Hunt and Binu John even this book is good expecially the java performance troubleshooting guidelines are good.

Thanks,
Ujjwal Soni

How To Handle Downtime During Site Maintenance

2015-04-21T05:43:00.002-07:00

Hi,

I came across a great article to handle downtime during website maintainence. I've shared the link below.

http://moz.com/blog/how-to-handle-downtime-during-site-maintenance

Thanks,
Ujjwal

error-message-401-2-unauthorized-logon-failed-due-to-server-configuration

2015-04-21T04:37:00.000-07:00

I faced below error when i configured my project to a different machine, i checkedout my source code from TFS. This error mainly occours when Authentication Mode is wrongly configured in your IISExpress.

In order to resolve this error, click on your project and press F4 key. (Dont right click and click on properties as it will take you to a different page).

Change the settings as per above screenshot, disable anonymous mode and enable windows authentication. This will resolve this error.

Thanks,
Ujjwal

Microsoft MVC 70-486 VCEFiles

2015-04-10T05:41:00.000-07:00

Hi,

I have a collection of exam dumps for Microsoft MVC 70-486 VCEFiles which can be downloaded from below link.

https://drive.google.com/file/d/0B_af9FI8dQPKZm56clViX1lhaHc/view?usp=sharing

Thanks,
Ujjwal

Windows 10 for Raspberry PI

2015-03-13T06:04:00.000-07:00

Microsoft announced that windows 10 would be available for Raspberry PI. Although, this version will be quite different version than what is being used in Desktops and will be much faster.

New Raspberry PI tourbocharges with new Broadcom BCM2836 system-on-chip. This is a VideoCore IV GPU with four 900MHz ARMv7 Cortex-A7 cores. Also, there’s twice as much memory: 1GB LPDDR2 SDRAM.

Windows 10 for the Raspberry Pi 2 will be available for free for the maker community via Microsoft’s Windows Developer Program for IoT.

Have ordered my new Raspberry PI and waiting for it to be delivered.

Thanks,
Ujjwal

Hibernate is haunted by "ghosts"!!

2015-01-27T05:58:00.001-08:00

Hibernate Haunted By Ghosts

Features of MVC 6 and ASP.Net vNext

2014-12-16T22:33:00.000-08:00

1. MVC 6 added new cloud computing optimization system of MVC , web API, SignalR and entity framework.

2. The Microsoft make a bundle of MVC, Web API, WebPages, SignalR , That bundle we called MVC 6.

3. In MVC 6, Microsoft removed the dependency of system.web.dll from MVC 6 because it's so expensive. Typically it consume 30K memory per request/response.

Right now, in MVC 6 consume 2K memory per request response. It's too small memory consume.

4. Most of the problem solved using the Roslyn Compiler.

5. The ASP .Net vNext used the Roslyn Compiler, By using Roslyn compiler do not need to compile the application Its compile automatically the application code.

6. The .Net vNext is a cross platform and open source.

7. The .Net vNext has the new project extension project.json. Basically project.json contain the all dependency dll of the application.

8. In MVC 5.1 and 5.2 support to Enum and EnumHelper in razor views.

9. MVC 6 added new cloud computing optimization system of MVC ,

web API, SignalR and entity framework. The Microsoft make a
bundle of MVC, Web API, WebPages, SignalR , That bundle we called MVC 6. In MVC 6, Microsoft removed the dependency of system.web.dll

Encoding issue when exporting linq data to CSV C#

2014-11-21T06:02:00.001-08:00

Hi,

I had been generating export in csv format from C# Code.

I faced an issue where CSV content heading had some Currency symbols and those were perfectly getting displayed in CSV but when you open those in excel, it shows some corrupted symbols.

i managed to resolve it using below sequence of development tasks.

My Earlier Code

byte[] Bytes = GetFileDataBytes(filename);
return File(Bytes , "text/csv", "report-" + DateTime.Now.ToString("yyyy-MMM-dd") + ".csv");

My New Code

byte[] Bytes = GetFileDataBytes(filename);
var result = Encoding.UTF8.GetPreamble().Concat(Bytes).ToArray();
return File(result , "text/csv", "report-" + DateTime.Now.ToString("yyyy-MMM-dd") + ".csv");

Using Above code, i managed to open csv in excel with all special characters in it. :)

Thanks,
Ujjwal

Hike Messenger Download

2014-06-24T02:55:00.002-07:00

Hi,

Recently i downloaded Hike Messenger on my Note 3 mobile. I am already using whatsapp. The great feature i liked about Hike is the Location sharing feature, its really great. I'll post other features soon.

Thanks,

Ujjwal

Issue Rendering Large Table in Internet Explorer 9 using jquery modal box dialog

2014-05-30T11:28:00.000-07:00

Hi,

Recently i had to render large amount of data in an html table in modal dialog box. This worked fine in all browsers except internet explorer 9 specifically. The problem was some rows getting skipped while rendering.

I had a simple table structure in jquery template as below
<pre>
<tr>
<td>
value 1
</td>
<td>
value 2
</td>
<td>
value 3
</td>
</tr>
</pre>
and so on....

I struggled a lot to find the root cause and discussed it on many forums, some said its due to memory related issues in Internet Explorer 9 and some were questioning on the jquery table structure i have used.

However, i managed to resolve this simply by removing extra spaces from td tag. Something like below solved my issue :

<pre><tr><td>value 1</td><td>value 2</td><td>value 3</td></tr></pre>

Let me know if you have any questions.

Cheers,

Ujjwal

Saving handsontable data

2014-04-01T02:03:00.001-07:00

What prompted me to use handsontable

I was working on replacing an old Excel web control with a more user friendly and needed a JavaScript library that provided the functionality that I needed. After investigating several libraries I decided that handsontable provided me the best solution.

I thank Marcin Warpechowski, for creating this wonderful library. The community around this is very helpful and this library is rapidly evolving into an even better library!

What my solution involved

My project that I was implementing handsontable was a classic example of Web Forms with PostBack and code behind access of form elements directly.

How to save the data

I did not try to create a Web Form custom element, instead I just took advantage of what was already implemented. I started out with creating everything I needed to render a blank handsontable to my page where I was replacing this old control. You can get that from the handsontable demo pages.
I then added the JSON2 library, from Douglas Crockford's Github repository, to my project and included it in the page that the table is on.

Lastly, I used jQuery to bind an event on the form submission that ran a simple verification that there were no invalid cells in my table. If my table was completely valid, then the event would harvest the data from handsontable and with JSON2 serialize that data into a valid JSON string and save it into a hidden field that my code-behind would pick up. Once it is on the server you can do what you need to do to this.

How to retrieve the data

With Web Forms and the page I was working with, I needed to be able to repopulate the table with data that had traveled across my PostBack event. So just as I did with my form submission event, I wrote a specialized page load event that populated an object for my handsontable to use during it's creation.

My event just listens for the ready event of the page and then looks for that hidden field I created to save the data. It pulls the data out of the hidden field and uses JSON2 to deserialize the object out of the string and that result is passed to my handsontable create table method.

var hst = (function () {
var $container = $("#hst");

$container.handsontable({
startRows: 8,
startCols: 6,
rowHeaders: true,
colHeaders: true,
minSpareRows: 1,
contextMenu: true
});

hst = $container.data('handsontable');

var $dataLocker = $("#dataLocker").val();

if ($dataLocker.length > 0) {
var data = JSON.parse($dataLocker);

hst.loadData(data);
}
return hst;
})();

// Enable a click handler for the button to save data and submit the form
$("#saveContent").click(function (e) {
// Save the table data before sending the form
$("#dataLocker").val(JSON.stringify(hst.getData()));
$("body > form").submit();

});

using System;
using System.Collections.Generic;
using System.Web.UI.HtmlControls;
using Newtonsoft.Json;

namespace HandsonDemo
{
public partial class _Default : System.Web.UI.Page
{
protected HtmlInputHidden dataLocker;
private List<List<int?>> Data = new List<List<int?>>
{
new List<int?> { 1, 2, 3, 4, 5, 6 },
new List<int?> { 7, 8, 9, 10, 11, 12 },
new List<int?> { 13, 14, 15, 16, 17, 18 },
new List<int?> { 19, 20, 21, 22, 23, 24 },
};

protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
// if we are posting data to the server deserialize it so that we can manipulate it
Data = JsonConvert.DeserializeObject<List<List<int?>>>(dataLocker.Value);
}

// store the data object to be rendered to the handsontable
dataLocker.Value = JsonConvert.SerializeObject(Data);
}
}

}

CSS Score

2014-03-31T04:17:00.000-07:00

(Original Article at http://sgdev-blog.blogspot.sg/2014/01/css-score.html)

We all know that when many conflict css properties can be applied for one web element, it is by specification that the more specific properties will be applied. However, specific is an abstract word. Hence, it is better that we know about css score, or how browser choose which properties to override.

Browser categorize css to 4 categories with the specificity from high to low as:

1/ Style Attribute:

2/ ID: #some_id{ color: red;}

3/ Class, pseudo class, attribute: .some_class {color:green;}

4/ Elements: li {color:black;}

From W3C recommendation, the result of this calculation takes the form of four comma-separated values, a,b,c,d,1 where the values in column “a” are the most important and those in column “d” are least important. A selector’s specificity is calculated as follows:

To calculate a, count 1 if the declaration is from a style attribute rather than a rule with a selector (an inline style), 0 otherwise.
To calculate b, count the number of ID attributes in the selector.
To calculate c, count the number of other attributes and pseudo-classes in the selector.
To calculate d, count the number of element names and pseudo-elements in the selector.
Here is one example using this rule:

body#home div#warning p.message --> 0, 2, 1, 3

Please notice the comma ',' in the css score, it is there to remind us that the score b, c, d can be equal or bigger than 10. Still, the rule to compare is left to right.

Checking Javascript errors remotely

2014-03-31T04:02:00.000-07:00

Think of a scenario where your website has gone LIVE. Now there occurs a JavaScript error and because of that the record cannot be saved in database and this happens only with internet explorer 7. The client is now complaining. You checked this at your end to analyse but it seems to be working at your end.

For scenarios like above, i found a great tool which can help us to monitor JavaScript errors. Yes, but for this you need to add a script in the page where you want to monitor. Check below link

https://qbaka.com

Real-Time Distributed Software Development Using Eclipse

2014-01-28T06:30:00.001-08:00

Hi,

I recently came across a cool plugin that enables Real-Time Distributed Software Development Using Eclipse.

http://www.saros-project.org

What is Saros? What is it not?

Saros is an Open Source Eclipse plugin for distributed collaborative software development.

Currently, it works only with and within Eclipse. Saros users can use all Eclipse functionality as usual.

Saros is a real-time collaborative editor for eclipse projects.

All collaborators have an identical copy of Eclipse projects.
Two or more users can jointly edit files in the project.
Each user has and modifies his or her own copy of the file locally.
Saros keeps these copies in sync by transmitting each change to all of the other collaborators.

Saros supports up to 5 participants at once.

Saros is designed to at least work with two participants in a session - as inherent for pair programming.
But it supports up to 5 distributed parties in a session.

The initiator of a session, the host, has a privileged role.

Saros is not screen sharing, desktop sharing, or application sharing.

That means for instance that it does not support joint interactive testing.

Saros can be used in various scenarios:

Joint review	One participant ("driver") reviews the contents of one or more files together with other participants ("observers"). Saros is set to always show the observers the same region of text (program code or whatever else) that the driver sees ("follow mode"). At any time, any participant (driver as well as observers) can highlight text with the mouse for all the others to see. Also, any participant can become driver at any time.
Introducing beginners	Much like before, except that explaining rather than reviewing is the goal. Each of the beginners (staying in the observer role) can individually peek at other regions of the file or even other files without influencing the flow of the session for the others. To do that, s/he will temporarily leave follow mode.
Distributed Party Programming	Two or more participants work together in a loosely coupled fashion. They work independently much of the time, but can call one of the others to help whenever the need arises, for possibly only a very short time or for a longer episode. In this mode, distributed work can even be more powerful than working in the same room, as nobody needs to leave a seat to help multiple others in the course of an hour. Just think how this can speed up the coordination work just before release time after a code freeze!
Distributed Pair Programming	Is a particular form of Distributed Party Programming in which two people develop code or text in continuous close collaboration, discussing the approach and combining the best of their ideas.

Which ecommerce platform is right for you ?

2014-01-26T04:32:00.000-08:00

Responsive Web Design

2014-01-14T03:31:00.002-08:00

Upgraded to OSX Mavericks on my Mac

2013-11-01T04:36:00.003-07:00

Hi,

I upgraded my Mac with OSX Mavericks. Apple claims that they have made improvements on speed, multiple windows and yeah, they seem to have succeeded in that.

Upgradation process went smooth and it was quick and steady.

Cheers,

Ujjwal Soni