Gradle Primer

Gradle is one of the most versatile build tools, based on Groovy. It is extremely complex, and most of the programmers only require very little for their day to day activity. This article tries to provide a boost for whoever is currently using Ant or Maven and want or has to switch to Gradle.
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OAuth Step By Step With Implementation

This is a step by step presentation of how to use the google OAuth to secure your application. The source code is included, you can download it and customize it for your needs.

There are a lot of libraries available for OAuth implementation. This is an implementation from scratch grouped inside a servlet filter, the only library used is GSON. I wanted to use the Google libraries but wanted to do something useful for other identity providers as well.

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Angular JS Primer

This is a text to help you get up to speed pretty fast with angular.js. It is not complete and I don't want to say it is correct. It is the result of what I studied from one of the books existent on the market and I rush to write this article before I forget what I just learned. Read on... Continue reading

REST Web Services with Jersey

This is a "first steps" presentation of Jersey REST web services.

It is assumed you want to deploy on a regular Java application server. Client sample is provided as well, however it is well known the REST services are easy to consume without any convoluted technology.
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SP2-0750: You may need to set ORACLE_HOME to your Oracle software directory

You need to access Oracle database server from your linux machine, installed the Oracle client and you get the message above. Actually this is not the full message that you get, the full stuff is something like that:

$ /ora/fs0000/app/oracle/product/11.2/bin/sqlplus
Error 6 initializing SQL*Plus
SP2-0667: Message file sp1.msb not found
SP2-0750: You may need to set ORACLE_HOME to your Oracle software directory

So you start browsing the internet and people is asking you to check the msb files are actually there, that you got rights to read, some people will tell you that write rights are needed as well in some folders, etc.
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Tomcat Startup Takes Forever

The Problem

So you install your new machine, with Java, Tomcat and MySql and then you start everything. You use the very latest version of these products (currently Tomcat 8 and JDK1.8) and you expect the best. However, Tomcat starts very very slowly - anything between 2 minutes and 30 minutes.
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Linux Iptables Tutorial

Iptables is a tool that is used to configure the netfilter linux kernel module. This inspects all the incoming / outcoming network packets and decides what is to be done with each of them.

This article is not fully featured documentation, it only shows a number of commands and their functionality. Iptables capabilities are huge, however for most of the use cases the information present in this article should do.
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