Mehedi Hasan Khan

Mehedi Hasan Khan

Programmer, Entrepreneur, Tech enthusiast.

3 posts

Understanding Complexity (Asymptotic notations)

Big O Notation

Big O notation is used in Computer Science to describe the performance or complexity of an algorithm.
Big O specifically describes the worst-case (not exactly) scenario, and can be used to describe the execution time required or the space used (e.g. in memory or on disk) by an algorithm.

O(1) describes an algorithm that will

Securely store app data in Android - Android KeyStore to the rescue!

Securely store app data in Android - Android KeyStore to the rescue!

Storing app data

The go to option for Android developers for storing application data is the SharedPreferences and it serves its purpose very well. SharedPreferences stores all the data as plain text in a xml file. A capable user can get access to that file quite easily, hence it's discouraged to store sensitive data in SharedPreferences. But there are some

StepBuilder - Builder that guides you through the steps

StepBuilder - Builder that guides you through the steps

What is a Builder & Why?

Simply put, a Builder is a helper class whose sole purpose is to help build instances of a certain class. Now why would you need such a class? Let's see an example.


public class Server{
    final static int DEFAULT_PORT = 8080;

    private String protocol;
    private String url;
    private String ipAddress;
    private int port;
    private