Author: AOProgrammer

Java SE 8 Optional Class 0

Short Java 8 Optional Tutorial

If you’ve been programming with Java for some time, I am quite sure that you’ve heard of or first-hand experienced the NullPointerException.A NullPointerException occurs when the programmer (you..) try to perform some operation on a variable that hasn’t been assigned any value – hence, it is null. The Java 8...

Two reference types can point to the same memory location in Java 0

Java reference types

Reference types in Java are all the types that are not one of the primitive types. Primitive types are the most basic data types in Java – the only purpose of these types are to store simple values of one kind. The 8 primitive data types in Java are: short...

python programming language 0

Simple Port Scanner in Python

In this very short article I’ll present a simple port scanner written in Python. If you’re looking for a production ready, kick-ass port scanner, I highly recommend nmap. For those unfamiliar with port scans; When performing a port scan, you are in reality probing a server or a host for...

Visualization of a tree data structure 0

Inorder, preorder and postorder traversal

If you have been working with linear data structures like stacks and queues, you know that it is a pretty easy job to traverse them. They are linear, which tells us that they are also traversed linearly. One simply goes through one element at a time, in a linear fashion....

showing options in metasploit 0

Exploiting Windows XP SP3 using Kali Linux

In this article we’ll walk you through the act of exploiting a live install of Windows XP Service Pack 3. We’ll make use of the well known vulnerability in the netapi32.dll in the Windows Operating System. The vulnerability is in fact very dangerous because the attacker is not required to...

enqueue-in-priority-queue 0

The Priority Queue

The priority queue is a somewhat similar data structure to the queue. The difference lies in how the elements are being processed: A standard queue strictly follows the FIFO (First In Last Out) principle. A priority queue does not follow the FIFO principle. In a priority queue, the elements are...

Visualization of a queue data structure in java 0

What is a Queue?

Today I’ll cover the queue, which is a linear data structure. The workings of the queue are very intuitive and easy to understand, as it works just as a regular queue (i.e. in the grocery store). Unlike stacks,which follow the LIFO principle (Last In First Out), a queue follows the...

Singly Linked List and Doubly Linked List 0

Doubly Linked List in Java

In this article we’ll have a look at a data structure known as a Doubly Linked List. If you’re unfamiliar with Linked Lists, I highly recommend that you check out this tutorial on Linked Lists before proceeding. A Doubly Linked Lists (often abbreviated as DLL), is very much alike a...

Client Server Application using Java Server & ServerSocket tutorial 0

Java Socket & ServerSocket Tutorial

In this article you will learn how to program a very basic Client-Server application. The communication between the client and the server will be unidirectional. Said in other words, there will only be a one-way communication between the client and the server. We’ll also write some very simple tests alongside with this...

Basics of the Android Platform Architecture 0

The Android Platform Architecture

As an aspiring Android developer, we highly recommend you get a clear understanding of the Android platform – both it’s platform architecture as described in this article, and the activity life cycle. The Android Operating System is composed of a total of 4 logical layers, with a total of 5 sections....