Lessons

The history of the IDE, popular IDEs for Java The history of the IDE begins from the moment when programmers came up with the idea of combining 4 of the most commonly used software development tools: Text editor Compiler (or interpreter, depending on the language) Build...

Installing the plugin To make your life much easier, CodeGym created a special plugin for IntelliJ IDEA that lets you get tasks and submit them for verification in a couple of clicks. It's super convenient — you'll see for yourself right now. For now, the CodeGym plugin isn't included in the standard set...

Autocomplete (Tab) IntelliJ IDEA is a very smart development environment. Some people believe that it not just a great IDE for Java development, but the all-around best IDE in the world. Which, admittedly, is not far from the truth. For example, IntelliJ IDEA has this magnificent thing called auto-completion. IntelliJ IDEA parses...

Bug Programmers have their own slang, though many consider it to be technical jargon. In any case, you cannot avoid getting to know it. You need to dive into the detail. So let's dive in. One of the first words you will get to know is the word "bug", i.e. "insect". In the context...

Watch When execution of your program stops at a breakpoint or when you're stepping through one instruction at a time, you can look at the values of the variables known at the current location in the program. Let's write a program that fills a 10-element array with the numbers from 100 to 109. Example: IntelliJ...

Now that you've figured out how to work with one of the main development tools — the IDE (in our case, IntelliJ IDEA) — you can relax a bit. That's a joke. Of course, you won't be able to avoid doing some reading at home. This time, we advise you to read a couple of articles written by someone who is both a CodeGym graduate...

Did you know that before the final power lift and transition to Level 5, you need to relax a bit and watch a video from the "Do You Know?" series. This isn't just entertainment. It's part of the comprehensive curriculum developed by the pedagogical board at the secret CodeGym center. The video is dedicated to the technologies and progress achieved by mankind.

Good is the enemy of the best. To be better means to be better than the others, to surpass them, and to be different. You can't do what everybody else is doing if you're going to be the best. You need your own path. You can't be better at everything. While you're studying everything, somebody else is specializing in a narrow field. The best...

Usually one family lives in a private house, but an apartment building accommodates many. To send a letter to a family living in a private home, you need to provide a house number. But writing a letter to a family that lives in an apartment complex also requires an apartment number. An array variable is like an "apartment" variable. Arrays are super useful structures. It's time to study them!

An array is an ordered set of elements. It's like in an apartment building: each apartment has its own number. An array doesn't actually contain the apartments. Instead, it contains their numbers (that is, references to them). Clear as mud? Your mentor will explain everything! This lesson is about how arrays are arranged in memory and how we can live with it.

Working with arrays is easy. You just need to get used to the fact that we have not one element, but several, with a single identity. So let's take a look at some popular examples and consider how to populate arrays, initialize them, display them, and search for the smallest element. This knowledge is very useful for understanding programming as such.

It's time to tackle some interesting tasks about arrays. Otherwise, your knowledge will become meaningless, like the life of a bank clerk in a matrix... By the way, did you know that the matrix is an array? Only people familiar with the mathematical definition of a matrix will get a kick out of that. Let's reinforce the concept of arrays, and do (a few) more tasks.