Install and Configure Oracle Java ME Embedded on Raspberry Pi

By Abhijit Ghosh on Mar 17, 2015 10:14:14 PM

Raspberry Pi is a low cost, credit-card sized and fastest selling personal computer. In this article, we'll install and configure Oracle Java ME Embedded on a Raspberry Pi.


Design - a start-up approach to adopt developers' language

By Deb Kumar Basu on Mar 12, 2015 1:15:41 AM

I have to observe lots of developers as part of my job description. I sit back and stare at what they do all the time, how they communicate to each other, how they express their ideas and how easily they get into a fight in a design discussion.


Cucumber Quick Start Guide

By Soumen Chandra on May 31, 2014 2:10:18 PM

I have been told that, medically, Cucumber can cause indigestion. Let's see...


Build, Install and Configure Eclipse Plugin for Apache Hadoop 2.2.0

By Abhijit Ghosh on Apr 23, 2014 2:10:18 PM

Apache Hadoop Development Tools (HDT) is still in development phase. So, no official distribution of Hadoop 2.2.0 Eclipse Plugin is available now. But we can build the same using winghc/hadoop2x-eclipse-plugin. In this post, we'll build, install and configure the plugin with the Eclipse or any Eclipse based IDE (say, Spring Tool Suite) to ease the development activities using Hadoop framework.


Shell$ExitCodeException - Caused by: java.lang.NoClassDefFoundError: org/apache/hadoop/service/CompositeService

By Abhijit Ghosh on Feb 28, 2014 1:43:45 PM

If you are getting "Exception from container-launch:org.apache.hadoop.util.Shell$ExitCodeException" in FAILED application's Diagnostics (or Command prompt) and "java.lang.NoClassDefFoundError: org/apache/hadoop/service/CompositeService" in 'stderr' containerlogs while running any Hadoop example on Windows, then add all the required Hadoop jars to the property 'yarn.application.classpath' in yarn-site.xml configuration file.


Run Hadoop wordcount MapReduce Example on Windows

By Abhijit Ghosh on Feb 3, 2014 12:21:12 PM

In this post, we'll use HDFS command 'bin\hdfs dfs' with different options like mkdir, copyFromLocal, cat, ls and finally run the wordcount MapReduce job provided in %HADOOP_HOME%\share\hadoop\mapreduce\hadoop-mapreduce-examples-2.2.0.jar. On successful execution of the job in the Single Node (pseudo-distributed mode) cluster, an output (contains counts of the occurrences of each word) will be generated.


AttachNotSupportedException: Unable to enqueue operation: the target VM does not support attach mechanism

By Abhijit Ghosh on Jan 10, 2014 10:12:37 AM

Following exception occurs in Windows for IBM JDK 6 while executing a JUnit testcase which uses JMockit framework, in-spite of enabling the Attach API "" - java.lang.RuntimeException: Unable to enqueue operation: the target VM does not support attach mechanism


Maven Build Failure - Hadoop 2.2.0 - [ERROR] class file for org.mortbay.component.AbstractLifeCycle not found

By Abhijit Ghosh on Dec 22, 2013 1:39:42 AM

In the previous post on Build, Install, Configure and Run Apache Hadoop 2.2.0 in Microsoft Windows OS, many people have encountered Maven build failure issue ("[ERROR] class file for org.mortbay.component.AbstractLifeCycle not found") for Apache Hadoop Auth project. So thought of sharing the fix as a separate post.


Configure SSL/HTTPS support on Apache Tomcat 7

By Abhijit Ghosh on Nov 27, 2013 2:08:21 PM

By default, HTTPS / SSL is not configured and enabled in Tomcat Web server. SSL setup is required to make your web application accessible over HTTPS protocol. This post will guide you to configure SSL in Tomcat 7 Web server.


Get Redirections of a URL using Apache HttpComponents HttpClient

By Abhijit Ghosh on Nov 25, 2013 2:08:10 PM

Many websites use URL redirection technique to forward the original request from one location to another several times for different reasons (Domain forwarding, URL shortening, Privacy protection, Maintaining similar domain names referring single website, etc.). In this post, I'll try to demonstrate how to get all the redirections of a URL using Apache HttpComponents HttpClient. A live demo will be a bonus here.


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This site is mainly developed to share coding and technology learning experiences on java / j2ee based technologies.

Simple tutorials / codes have been shared to learn a new technology. Full source code is also available for download.