Java Class 101

Lesson 1

Sunil took the class through the basics of the Java Programming language, what it is, its main components and what you need to run a java programme on a PC. Below is a summary of what java is and how it runs. Its important to understand how this works for to run a Java program. As a student i found this flow chart and it summarised very well what Sunil taught us today.

Java is a very robust language we cant expect to learn everything. The important lesson today was that a Java program needs to be compiled first before it can run. Once its compiled it needs an interpreter to run.

Java has a huge spectrum and its important to understand this because you cant expect to specialise in everything. Its like Java is a language with a number dialects depending on the item its being developed for. On the spectrum there different "Javas" for different devices as shown below;

It was fascinating to learn all this especially because i have always wondered why we have Java SE or Java ME. It becomes important to know that once you know the Java language you can choose which development environment you want to focus on, mobile or desktop etc. Fascinating isnt it?

A particularly difficult area that Sunil touched on which needs to be understood from the very beggining to avoid common mistakes in Java is the to do with inheritance, polymorphism and abstraction. After the lecture i dug up some more information on youtube and found this interesting video.

Once we were done with this background Sunil took us through the a java basic statement as shown below;

Its amazing what you can learn in less than 2 hours. I found this a bit confusing but hey every language has what they call syntax. Its important to learn and understand this syntax because the computer needs to be told certain things for it to execute the instructions properly. What learnt today is if you mis spell anything nothing gets done by the computer. So this is important. Each language has its own syntax so does Java.

Sunil touched on classes and this video summaries very well what he taught us today.

Intro to Classes and Objects in Java

An introduction to classes and objects in Java

We then setup a proper environment on our machine for Java to run. You can watch this video for how to do that on your machine. The video is under 3 minutes. Once you do this you can now run Java programs on your machine.

How To Get & Set up Java JDK

In this video I show you how to install java JDK (Java Development Kit) Link: http://www.oracle.com/technetwork/java/javase/downloads/index.html ---------- My Channel: http://www.youtube.com/tekcomputing Twitter: http://www.twitter.com/twtekcomputing Google + : http://www.gplus.to/tekcomputing Website: http://tekcomputing.tk Apprat: http://apps.facebook.com/apprats/?c=tekcomputing&va=1&fu=&sa=

Quite a productive lesson! Here are the complete notes of what we were taught to day. I summarised what i learnt today to show how easy it is easy to learn Java. Finally in this lesson Sunil showed us how some companies have come up with a way of making it easy for us "Developers" to create our source code using an IDE. He spoke of Netbeans and Eclipse and showed us how Netbeans formats a text file for us. 

Further reading.

1. Java tutorial 

2. Abstraction 

3. Inheritance 

4. Polymorphism

• What is polymorphism 
• What it does

Download lesson 2 

Lesson 3 

Lesson 3 was all about learning about

• Variables
• Primitive Data types 
• Arithmetic Operators 
• Type conversion

I started my Java Journey on the 11th of May 2017. I am on mission to prove that with determination and the desire to learn, i can become a Java programmer. I sharing my experiences to encourage anyone who has always wanted to program but thought it was too hard or impossible.

Here i talk about my third lesson and my very first java project.

Being new to Java all this is very new to me but not at all surprising. I always wanted to program and that helps.  Its all making sense because Sunil, our volunteer lecturer is simplifying everything. Sunil is not assuming prior knowledge of Java and this helps. Working in Netbeans is exciting too, as errors are highlighted and you are able to quickly spot an error. Its nice to know that work has been done to ease the tasks!

My first assignment was to be build a calculator and i am so happy with feedback that i received from Sunil. I did a lot of research and it was great to receive feedback about the right things i did during this assignment. My journey so far has been great and i am learning more and more each day. Its important to reasearch after each lecture and practise typing the code. Given somethings i may forget but its nice to know that i can alwys go back to my notes or the internet.

One of the exciting concepts i learnt today about programming in general is that a lot of thought has been given in coming up with all the components of a programming langauge, especially Java. Everything is there for a reason and more importantly some things are done to simplify how we write code. Take for example what i used during the my calculator example. I chose the switch statement because it made sense to separate each calculation. As a beginner i found out that i computer programme does what its told to and the programming language translates this into the responses it gives. In short programming is translating your ideas into code. If you cant think and break the problem into logical parts it will not be easy to write code thats simple and straight to the point. While the programme can only do one cycle, ie solving just one problem and break i know as times goes i will learn how make it into a real calculator that can solve one problem after another! 

Sunil also liked the way i wrote my code becuase i let the user be guided by my programme with step by step instructions. As i coded the calculator it was interesting to see how i had to break down the problem into sections. First i declared my variables then i selected a library to scan for inputs and store inputed values. You see there a repetitive tasks in programming and these have been made into libraries that we can simply import into our programme and call them to complete a task. Thats brilliant. The next step was tell the computer to add the inputed values, subtract, divide and multiply. The next step was to come up with the result and have it change as the choice of calculation was changed. This was the hard part, but once i figured it out, I marveled at how simple it was afterwards. Sunil had shown us in lesson 1 how to print out results and it was nice to see how i needed to recall what i had been taught to complete this assignment. It did work from the get go. I had to figure what wasnt working and attend to it. It took some time but i got it done! 

A lot of what i am learning as a new Java programmer is hard but what i dont understand i ask Sunil or search on the internet. This is the beauty of this course. 

In today's lesson i learnt quite a lot too. Much of what i applied in my calculator assignment was covered today. You need variables, you have primitive data types and operators and so on. These things were part of my calculator asssignment and its great to see how they all work together. I am looking forward to learning more! 

If you want to join me in the classes register on the website 

You can download the notes of today's lesson here