Programming Theory

Best practices, structuring of code, dissecting algorithms and talking about the “Why?”

Using Hashes To Check If A File Changed in VB.NET

Once in awhile you may want to check if a file has changed its contents in some way. Perhaps you are monitoring a log file or checking to see if an exe has had a virus mess with it. One way you could do this is by hooking up a FileSystemWatcher object and monitor the file. This might be a good approach for more elaborate programs where you also want ...

Introduction to a SkipList Data Structure in Java

Hello everyone! The other day I was approached by macosxnerd101, a newly minted moderator at Dream.In.Code, and asked to contribute to a new thread coming up on Java data structures. Now most of the new programmers here know of the basic data structures like binary trees, arrays, heaps or stacks. Many of these topics I knew would be covered by other contributors to the thread. So I decided to introduce ...

Login to a Website from Java

Historically the question "How do I login to a website from X Language?" gets asked from time to time on Dream.In.Code. The answers to this question has not been the greatest and these questions tend to be largely ignored. I intend to put an end to this for the Java language with a simple example. The answer, while simple, does expect the reader to be at least familiar with how ...

Convert Infix to Postfix in C++

Remember those pesky equations that baffled you in like 1st grade? Addition and subtraction along with their friends multiplication and division. Hey, you wanted to go play kick ball or chase that girl around the playground... not to hook up with her but to put dirt in her hair. Well, you probably learned to write your equations in infix form like 3 + 4 or 2 * 7. This makes ...

Rijndael Class Example for File Encryption in C#

Hello readers! It has been awhile since my last post. Lots of things have been going on lately and I have been busy developing some great code for some great people. In this entry I am going to show you a bit of plain text file encryption using the Rijndael Algorithm. This example is a fairly simple one and I hope to explain the basics as I move through an ...

Playing with Recursive Directory Diving in VB.NET

So recently someone asked about listing files from several directories but only to a given depth. They were using a DirectoryInfo object, as they probably should, to get a list of files. There was a problem with this however since the constructor of this object only offers a version where you specify no recursion on the sub directories or full recursion and get all the sub directories. This is an ...