techcrux

Java Data Structure - Part1

2012-02-09T23:56:00.000-08:00

My dig at Java data structures - Part1 - How do hashtables/HashMap work ? At the heart of the hash table algorithm is a simple array of items; this is often simply called the hash table. Hash table algorithms calculate an index from the data item's key and use this index to place the data into the array. The implementation of this calculation is the hash function What happens if two keys

Memory footprint of java primitives

2011-12-10T08:36:00.000-08:00

Memory foot print of Java primitives Java Primitive Data Types Data Type Description Size Default Value boolean true or false 1-bit false char Unicode Character 16-bit \u0000 byte Signed Integer 8-bit (byte) 0 short Signed Integer 16-bit (short) 0 int Signed Integer 32-bit 0 long Signed Integer 64-bit 0L longfloat Real number 32-bit 0.0f double Real number 64-bit 0.0d Next -

Gretty - example - web-service

2011-12-10T01:51:00.001-08:00

import org.mbte.gretty.httpserver.* @GrabResolver(name='gretty', root='http://groovypp.artifactoryonline.com/groovypp/libs-releases-local') @Grab('org.mbte.groovypp:gretty:0.4.279') GrettyServer server = [] server.groovy = [ localAddress: new InetSocketAddress("localhost", 8080), defaultHandler: {

Sample code - Kilim

2011-12-10T01:21:00.001-08:00

A simple Calculator example -pretty naive but then demonstrates using Actor based model in java In Kilim a thread must extend Task object and implement the execute method which should throw Pausable exception. Kilim weaver (read it as byte code enhancer) interprets classes containing operations throwing Pausable exception and weaves(enhances) it. import java.math.RoundingMode; import

An actor framework for Java concurrency

2011-12-09T20:49:00.000-08:00

Recently my curiosity towards learning something new , bumped me into a framework called Kilim. Ya that's right , not sure how many of you have heard about it. Goal of this framework - to introduce Actor based concurrency to java ala. making the model similar to Erlang and Scala Why do we need this switch from thread based model to Actor based model when it comes to concurrency - thread based

Querying the memory usage of a Java object

2011-12-08T05:26:00.000-08:00

Creating the instrumentation agent class - would work with Jdk 5 and above The JVM will pass to our method an implementation of the Instrumentation interface, defined in java.lang.instrument. In turn, this interface defines the method getObjectSize(). So for example, if we want to measure the memory usage of an instance of SomeClass, our agent code would look as follows: import

Hello world with gretty

2011-12-08T01:38:00.001-08:00

Gretty is a simple web framework for both building web servers and clients. Built on top of netty, it supports NIO style http server, asynchronous http client. It also supports both websocket server and client. It's designed to be light weight and run as a standalone embedded solution. It's written in Groovy++. But you can use it with pure Groovy, Scala or even Java. Do bear with me

Tortoise svn for linux

2011-11-24T05:23:00.000-08:00

digg_url = location.href; A very useful tortoise svn replacement for developers using Linux but just cant live without a graphical svn client http://www.krishnashasankar.com/2008/11/tortoise-svn-in-linux-ubuntu-alternatives-here/ var addthis_pub = 'shammur';

Spring MVC and Spring WS in the same app - how to's

2011-10-19T01:28:00.000-07:00

digg_url = location.href; Hosting Spring MVC controller and Spring-WS service in the same web application - This is fundamentally useful when developing an application which has its own view and additionally needs to host a bunch of services to its clients. So how do we do this ? 1. web.xml of the web app needs to have 2 set of dispatcher servlets configured &

CHART - Java collection framework perfromance

2011-10-17T10:20:00.000-07:00

digg_url = location.href; var addthis_pub = 'shammur'; Also Read The Clean Coder

How to get C like performance in Java

2011-10-05T01:19:00.000-07:00

The JVM does implicit bounds checking on array access and updates. This has a small overhead - you can unsafely eliminate this (and open yourself to buffer overflows and other problems) using the the Unsafe class or direct buffers. Use memory-minimized collections to reduce memory usage. You can use Direct memory to store data how you wish (this is what BigMemory uses). Use blocking IO in

6 Ways Not to Scale that Will Make You Hip, Popular and Loved By VCs

2011-09-29T02:56:00.000-07:00

digg_url = location.href; Tips from - High Scalability Recently "hot" and newer tools typically have not been tested for scalability, and are risky to use in where you need scalability. You should be resource monitoring, performance testing, monitoring traffic, load testing, and doing tuning analysis using statistics and mathematical modelling. Design and implement your applications

50 Strategies For Creating A Successful Web 2.0 Product - 41/50

2011-09-27T02:54:00.000-07:00

41. Understand your business model and use it to drive your product design. Too many Web 2.0 applications hope that they will create large amounts of traffic and will then find someone interested in acquiring them. Alternatively, some products charge too much up front and prevent themselves from reaching critical mass. While over-thinking your exit strategy or trying to determine your ultimate

50 Strategies For Creating A Successful Web 2.0 Product - 31/40

2011-09-27T02:51:00.001-07:00

50 Strategies For Creating A Successful Web 2.0 Productdigg_url = location.href; 31. Understand and apply Web-Oriented Architecture (WOA). The Web has a certain way that it works best and understanding how HTTP works at a deep level is vital for getting the most out of the unique power that the Internet has to offer. But HTTP is just the beginning of this way of thinking about the Web and how

50 Strategies For Creating A Successful Web 2.0 Product - 21/30

2011-09-27T02:50:00.003-07:00

digg_url = location.href; 21. The link is the fundamental unit of thought on the Web, therefore richly link-enable your applications. Links are what make the Web so special and fundamentally makes it work. Ensuring your application is URL addressable in a granular way, especially if you have a rich user experience, is vital to participate successfully on the Web. The Web's link ecosystem is

50 Strategies For Creating A Successful Web 2.0 Product -11/20

2011-09-27T02:49:00.000-07:00

digg_url = location.href; 11. Variability in the productivity amongst programmers and development platforms each varies by an order of magnitude. Combined together and your choice of programming talent and software development platforms can result in a 100x overall effect on product development productivity. This means that some teams can ship product in as little as 3 months and some

50 Strategies For Creating A Successful Web 2.0 Product - 1/10

2011-09-27T02:48:00.000-07:00

digg_url = location.href; 1. Start with a simple problem. All of the most successful online services start with a simple premise and execute on it well with great focus. This could be Google with it's command-line search engine, Flickr with photo sharing, Digg with user generated news. State your problem simply: "I make it easier to do X". Focus on solving it elegantly and simply, only add

The Clean Coder

2011-09-24T06:31:00.000-07:00

digg_url = location.href; Before even getting into the book, it is good to know the style of Robert Martin, affectionately known as "Uncle Bob" to many people. Bob is a former preacher who comes at life — and topics he teaches — with a no-holds-bar approach. So when he approaches topics such as "Professionalism" and the software industry, I come expecting passionate discussion and serious

My 2 cents on Hibernate

2011-09-21T05:40:00.000-07:00

Few hibernate experiences - 1. Implementing hashcode and equals on hibernate entities - Remember hibernate returns a set of entities when you have a one to many or a many to many relationships. Accoring to Set rules - no two objects can be equal and hence it becomes all the more important to define the right equals implementation for your hibernate POJO's Rule to thumb -

GCompris -

2011-09-19T03:57:00.000-07:00

GCompris is an educational software suite comprising of numerous activities for children aged 2 to 10. Some of the activities are game orientated, but nonetheless still educational.We are working on a port to Android. Obviously this involves a lot of work, volunteers are always welcome. Please drop an email to me "mshamanth@hotmail.com" if you would like to

Caching Scenarios

2011-01-16T05:03:00.000-08:00

Caching ScenariosCaching is a quick and easy way to save roundtrips between your application and where you store your data. However, it’s not as easy as just snapping a map into your application – to really leverage a cache, you not only have to understand where a cache can be used, but how it can affect what your application does and how your architecture is used.Definition of cachingCaching is

Technical Debt

2010-12-20T06:14:00.000-08:00

What is Technical Debt - Technical Debt is a wonderful metaphor developed by Ward Cunningham to help us think about this problem. In this metaphor, doing things the quick and dirty way sets us up with a technical debt, which is similar to a financial debt. Like a financial debt, the technical debt incurs interest payments, which come in the form of the extra effort that we have to

One of the Most Powerful Debugging Practices

2010-12-15T20:29:00.000-08:00

Dzone promoted a link called "One of the Most Powerful Debugging Practices," showing the use of a trap. The example is in C#, but a Java version is offered. Interesting thought - worth it? Add Trap() instances all over the place to cover all the execution paths and have it throw a runtime exception so that the debugger would pick it up and help you step run

How much time out of your day does IBM waste?

2010-12-14T23:40:00.000-08:00

Blogger Chris Hardin has written up a post about the breakdown of time wasted while using WAS and RAD, a brutal loss of at least two hours while predicting much more (with a lot of "oftens" and stuff.) It makes you wonder: what would the breakdown be with other products?digg_url = location.href; var addthis_pub = 'shammur';"1 hour sporadic time waiting for

Top 10 reasons i don't like JSF

2010-12-14T07:44:00.000-08:00

Bruno Borges posted the "Top Ten Reasons I Don't Like JSF," offering these reasons along withe xplanations:Extra step when defining a project's architectureFragmented CommunityFragmented DocumentationComponent IncompatibilityCaveats on some scenarios because of different implementationsDesigners and developers roles mixedDoes not improve usual web development processNon-functional