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Java programming: Learning from scratch
Well, you're here. And you find yourself in a sticky situation! This dark corridor leads to a distant door (see, young robots like you are crowding there). Behind the door, is the secret CodeGym lab, where you will learn Java. I don’t know your background nor have I any idea where you studied or what you studied to become. I only know that cranking through 40 levels with 1200+ tasks will make you a programmer.
How to use CodeGym
The secret CodeGym center's control panel has a simple and intuitive interface. But confused at the abundance of new information, newcomers sometimes don't access it in the best possible way, or they don't notice the obvious. So it's time to go over our buttons/arrow/icons to accelerate your training.
The virtual machine and the first command
Ready for the first program
Just imagine: within 10 minutes you will be writing your first Java program! But first a wise teacher will tell you something else important about the command to display text on the console (though the true meaning of all the elements of the command will be revealed to you a little later) and class methods.Classes and methods - these words will gradually become meaningful.
Ellie, variables, and data types
To work in this changeable world, a program needs variables, which are like boxes for storing data. Just as you can't put an elephant in a matchbox, these variable boxes need a specific type (for example, "elephant box") to stop people from trying to fill them with inappropriate items. This lesson is about variables in Java, basic variable types (String, int, double), and the assignment operator.
What are compilers?
What's so great about Java that it is creating such a sensation? Every computer's alphabet consists of 0 and 1, but these symbols are used in different ways, depending on the architecture, to create words. The Java virtual machine and its trusty compiler (a program that translate from a programming language to the computer's language) solve this problem: Java works everywhere (almost)!
Wow, another human woman. But this time with black hair. How interesting. — Hi, my name is Kim. — Hi, and I'm Amigo! — Yes, I know. I was the one who came up with your name. Diego wouldn't have thought of it on his own. Amigo's thoughts again raced at the speed of electrons. Mmm... What a cute... I wonder if she likes...
What they don't teach you in school
The super secret CodeGym training center has both standard lessons and entertaining lessons. But we don't have them just for the sake of having them. They will teach you loads about your future field of employment! It's time to relax a bit and watch a video about your future colleagues.
Summary of Level 0
So, the first, or rather the zeroth (Programmers count from zero. Remember that.) has come to an end. The final lesson in Level 0 is the first summary of your results and an opportunity to complete test tasks. There are three of them. They are not complicated, but they will help reinforce your understanding of the material about variables, int and String types, screen output, and comments.
You've leveled up!
Research conducted by the secret CodeGym training center in 3101 showed that even the best students studying the most fascinating and advanced technical skills sometimes lose their motivation. That's why we've got a super specialist who has developed a special motivational program in the form of accessible lessons. Don't skip them. They're very helpful.
Introducing the program
The first level. It sounds not very cool, but if you consider the fact that programmers count from zero, it means you've got your first level-up as a CodeGym student. This lecture will not only give you a serving of entirely new information about the structure of a Java program, but also systematize and deepen your knowledge. We'll do this often. It's effective!
It's time to meet two wise aliens. But they're not just aliens, they're mentors. They represent different sides of the same force. And only you can choose which side to follow. The first gives power. The second develops perseverance. The choice is yours, my young student!