Recently someone asked me what I would recommend them to do in order to become a backend Java engineer. Keep in mind that this advice is based on my opinion and years of professional experience conducting interviews. This pathway represents the skills I look for when interviewing Java engineers.

1. Get Comfortable with Java

Learn the syntax of the language:

• Declaring variables
• Arithmetics Operators
• If, Else If, Else statements
• While and For loops
• Creating methods and passing values to methods
• Creating classes and calling them from other classes
• Interfaces
• Abstract classes

It’s also a good idea to learn the basic data structures built into Java:

• Basic data types (int, float, String, etc)
• Arrays

2. Develop Problem Solving Skills

Problem solving skills are the most important skills an engineer can have. I recommend picking up the book Cracking the Code Interview by Gayle Laakmann McDowell and going through the exercises in the back. I came across this book early on in my career and it completely changed the way I approached problems and coming up with solutions.

I also recommend you start to understand basic computer science theory:

• Time and space complexity
• Difference between data structures and when to use them
• A few sorting algorithms (Quicksort, Merge Sort, etc)
• Design patterns

3. Learn a Microservice Framework

APIs and, especially, Microservices are the bread and butter of backend engineers. I recommend starting with Spring Boot as a lot of companies are using it. Try to find some tutorials or videos online for Spring Boot. They should walk you through basic database stuff as well.

4. Learn a Database

As a backend engineer you’ll most likely be working with some kind of repository. I recommend you learn a SQL database like MySQL. Learn to do the following things:

• Create tables
• Insert into a table
• Select from a table based on some criteria
• Delete from a table
• Do a join between two tables

5. Practical Advice

Try building solutions that solve a real problem in your life. This is the best way for the material to stick and to motivate you to explore further.
By the time you get past Cracking the Code interview I recommend you start applying for jobs. It may take a few tries to find your first job but at least you’ll get some practice interviewing and, more importantly, you’ll start to understand what kind of skills you need to work on in order to land the job.