Sort An Integer Array With the Quicksort Algorithm And Java

Circling back to data structures and algorithms, we’re now going to take a look at the efficient sorting algorithm known as Quicksort.

Quicksort via Wikipedia:

Sometimes called partition-exchange sort, is an efficient sorting algorithm, serving as a systematic method for placing the elements of an array in order.

The idea behind Quicksort is to take a large array of values and divide it into two smaller arrays, doing this recursively, and swapping elements.

This is one of the fundamental algorithms you’ll learn in any computer science course. It is also a very good question that could be asked in a job interview for an engineering type position. I’m going to help you through it using Java.

Various Graph Search Algorithms Using Java

If you’ve been keeping up with my blog, I’ve made a topic regarding Binary Search Trees, but another very important topic in computer science and software engineering is in regards to Graphs.

Graphs via Wikipedia:

A graph data structure consists of a finite (and possibly mutable) set of nodes or vertices, together with a set of ordered pairs of these nodes (or, in some cases, a set of unordered pairs). These pairs are known as edges or arcs.

When interviewing for a new programming or software engineering position, it is incredibly likely that you are asked a question on this topic. Because of this, I figured it would be a good idea to go over a few of the Graph search algorithms.

Parse An XML Response With Java And Dom4J

Previously we’ve explored how to parse XML data using Node.js as well as PHP. Continuing on the trend of parsing data using various programming languages, this time we’re going to take a look at parsing XML data using the dom4j library with Java.

Now dom4j, is not the only way to parse XML data in Java. There are many other ways including using the SAX parser. Everyone will have their own opinions on which of the many to use.

Parse A JSON File With Java

Recently I was tasked with reading a JavaScript Object Notation (JSON) file using Java. In my project, the JSON file contained properties information to be used inside the application.

There are many libraries available for reading or parsing JSON data in Java, but in particular we are going to be using the library found on json.org.

Why I’ve Gone Hybrid Over Native For Mobile Apps

I started developing mobile Android applications in late 2011. It wasn’t until 2012 that I released my first application to the Android Marketplace, now known as the Google Play Store. Up until early 2014, I only made native Android applications using the official Android SDK. As of now, I have only been using web technologies to create mobile hybrid applications for Android and iOS.

The following will explain why I’ve chosen to develop using modern web technologies rather than native mobile languages.

All About Binary Search Trees, In Java

If you’re pursuing a degree in computer science, you’ll probably experience Binary Trees in one of your first semesters of school. After seeing them in one of those first semesters, you probably won’t see them again until you’re interviewing for a job.

While interviewing for software engineering or programming positions, you may get many questions regarding Binary Trees and Binary Search Trees. Take this as a refresher in case this is a subject you might have forgotten over the years.

Validate Bracket And Parenthesis Combos Using Stacks

Job interviews for software engineering and other programming positions can be tough. There are too many things to study, and even then it still might not be enough. Previously I had written about a common Fibonacci number algorithm and finding duplicate values in array.

Those skill refreshers were written in JavaScript. This time we are going to take a turn and validate bracket combinations using the Java programming language.