Developer's Canvas

Spring Aop (Part 1)

By admin on May 14, 2013 in Spring Framework

Spring is an open source application framework and IoC (inversion of control) container for the Java platform. More details and a detailed explanation of IoC or Dependency Injection (as IT community decided to call it) can be found in this article by Martin Fowler. In this article I want to talk about how spring uses [...]

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Hibernate caching feature and how to use it

By admin on March 15, 2013 in Hibernate

Hibernate is a really cool ORM tool that can be used from a Java project , as an intermediate layer between our project and the underlying database. In this example I will use MySql as the underlying database, although any database can be used to support our application. The IDE that I will use is [...]

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Run Arch-Linux from a flash drive

By admin on December 6, 2012 in Linux

Many users have a single operating system installed at their laptops and they don’t want to risk loosing their job by installing a second operating system (especially these users that rely on one single internal hard drive). So here is a way to install a popular linux distribution called arch-linux , on a usb flash [...]

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NetBeans tips

By admin on February 2, 2012 in Netbeans

NetBeans is a really great tool that can help on the rapid development of Java Web Applications or Java Desktop Applications, with a great community and many fans (mostly Java Developers). This article discusses upon a specific flow that I have found, that seems to be a bug inherited from earlier versions of Netbeans IDE. [...]

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A great tool called ‘Regular Expressions’

By admin on November 14, 2011 in Regular Expressions

The simplest way to use regular expressions is when we search for a single word. For this article , we’ll use the command line tool called ‘egrep’ (egrep is available for many systems, like DOS, Windows, MacOS and Unix) So let’s say that we have a file called article1.txt like this : We want to [...]

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Perl tips (part 1)

By admin on November 1, 2011 in Perl

- Variable Interpolation This is a classic between many programming languages. When we use a double quoted string, for every variable that we put inside the string , we get variable’s value as part of the output when we execute our script. For example : #!/usr/bin/perl #script1 use 5.012; my $name = “Stavros”; print “My [...]

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Mac OS Lion 10.7.2 memory problems

By admin on October 21, 2011 in Apple

As I was working using firefox I noticed the appearance of the well known ‘beach ball’ that shows that the operating system is struggling to acquire resources. Immediately I ran Activity Monitor to see what is going on. Here is the situation that I’ve got : Then I stopped all running applications and [...]

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Custom sorting in python

By admin on October 16, 2011 in Python

A classic way in python to sort a list is by using the sort() function. For example if we have a list >>> x = [3, 8, 4, 2, 9] …we can use sort() like this… >>> x.sort() >>> x [2, 3, 4, 8, 9] As you can see our list is now sorted. [...]

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Executing our first script

By admin on October 15, 2011 in Command Line

Today we’ll see how to run our first program from the command line. First we should be in our home directory. To do that type : > echo $HOME In my case, executing this command has the following result: /Users/myUserName Now we must select a directory for the script we want to execute. When [...]

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