Let’s be honest: you started learning Java because you had a goal. And this goal most likely is to find a job as quickly as possible and build as successful a career as you can. But when will this career start? How long does it take to apply for a position and get the job? What should you know to be able to say: “I can be a Java developer”?
Start from the basics
There are different jobs that may become your goal (and we’ll talk about them later), but no matter what direction you choose, you must first learn the basics. This primary knowledge is called Core Java, and it consists of:
Java syntax. It’s like learning the alphabet: you can’t proceed if you don’t know it. You must learn about variables, classes, data types, and basic constructions (for example, loops, branches, and special operators).
Concepts of object-oriented programming (OOP). It’s the most crucial concept for the Java language, so you should spend some time digging into it. You must know what class inheritance is, learn about data and behavior abstraction, polymorphism (object’s ability to take many forms), virtual methods, etc.
Java Collections Framework. A collection is a single unit of several objects. The framework allows you to store or use a particular group of objects. The basis of the collection is a data structure: for example, lists, sets, maps, etc. So, it’s helpful to learn about different data structures at this point.
Multithreading. Java allows creating programs consisting of several parts that can be run at the same time. It means you can solve several tasks concurrently, increasing efficiency and optimizing resource usage. Some beginners may find the idea of managing a few threads at once a bit challenging. Still, if you grasp it, you’ll have a competitive advantage compared to other Java learners.
I/O Streams. Input/output streams (flows of data) present another piece of Java’s basic knowledge. There are several types of streams: byte streams, character streams, standard streams. It makes sense to study them all.
Exception Handling. When you run the program, something unexpected can happen – it’s called an exception. So, in an early stage of the Java learning process, it’s essential to find out about the exception handling mechanism, exceptions hierarchy, the distinction between an error and an exception, etc.
So, in general, the starting point is to learn basic principles, terms, and concepts – and understand how to use them when coding. After that, you can go to the next level.
Choosing your direction
Further Java learning requires a more precise understanding of the type of job you’re aiming for. There are three main directions: Java developer, Android developer, and Java developer for QA Automation. The learning process should be based on your decision.
1. Java developer. The knowledge you need here may be very different depending on the company and projects you will be working on. But I created the general list of topics you’d better uncover before applying for a job (even as a Java trainee). In addition to Core Java, you’ll need to study:
- Java 8 (in particular, lambdas – special functions which don’t belong to a specific class)
- Tools like GitHub, Eclipse, Maven
- JDK API
- Testing Libraries (JUnit)
- Spring Framework
- Spring Boot and Spring MVC
- Hibernate
- JDBC
After you get the first job, it will become clearer what to study next and which parts of the language you must pay the most attention to.
2. Android developer. This job is for you if you like working on mobile apps. There’s a huge demand for Android developers, and it’s not likely to decrease soon. According to the BankMyCell statistics, in 2021, the number of smartphone users in the world reached 6,378 billion. And Ericsson & The Radicati Group’s estimated number of smartphones in 2025 is 7,33 billion. So, choosing this career path will guarantee you a job for many years.
But to get the first position, you’ll need to learn (after Core Java, of course) at least:
- Testing Library (PowerMock/Mockito, JUnit)
- Basic usage of Git
- Android Studio
- Android Software Development Kit
- MVP/MVVM CleanArchitecture
- Shared Preferences
- Android NDK
- SQL/DataBases
- UI Design (layouts, activity, fragments, etc.)
- Intents
- Retrofit
- RxAndroid
- Kotlin
3. QA Automation. This career path is also very popular and probably the easiest to start among the three presented options. But it requires knowing Java and some other technologies pretty well, so just Core Java won’t be enough. You must also learn the following:
- Testing Libraries (JUnit)
- IntelliJ IDEA
- Selenium RC/WebDriver framework
- Page Object Model
- Basics of web design (HTML/CSS)
- Databases (SQL)
What is the most efficient way to learn?
Learning Java requires not only time but also motivation and self-discipline. Most people struggle to study regularly by themselves. Another obstacle they face is the lack of motivation. “What if I spend many hours but won’t be able to find a job?” they think.
So, if you’re not a Superman or Superwoman when it comes to willpower, guided learning is the best choice. You can find a mentor among professional Java developers and ask them questions from time to time. But in this case, you still may not be entirely sure you’re moving in the right direction with your studies.
The better option would be to find a Java course from an educational company you trust. CodeGym is at the top of the list here. This global company has nine years of experience in teaching Java and over 30,000 graduates from 40 countries. 95% of them have already found a job. Recently, CodeGym entered the Indian market, and now you have an opportunity to study at Java University, the newest CodeGym 12-months course to learn Java. What’s so special about it?
First, you’ll find lots of practice here. After every online lesson, starting from the very first one, students get their home assignments. Hence, they start coding as soon as possible. Also, there’s a very convenient auto-check on the CodeGym platform, so students can see their mistakes and correct them.
Second, students get any kind of help they need. At Java University, they can communicate with mentors, who are professional Java developers, during online classes or in the Slack channel between lessons. Every question will meet its answer.
Third, in 12 months at Java University, you’ll not only get all the knowledge you need to become a Junior Java developer but also create a portfolio of projects. It means that you’ll become a valuable candidate for IT companies.
And last but the most pleasant, every graduate of Java University will get a guaranteed job offer. CodeGym Career Center will help you polish your CV and prepare for interviews.
Becoming a Java developer might be the most exciting adventure of your life. In this job, you’ll always be able to face new challenges and study something new. Maybe now it seems like a long path (especially if you’ve just started to learn Java), but believe me: when studying is fun, time flies! And if you want to see a clear career path ahead of you, Java University may be just right.