Apply your knowledge by building a project

Privacy is an important matter is the realm of the Internet. When sending a message, you want to be sure that no-one but the addressee with the key can read it. The entirety of the modern Web is encrypted - take https for example! Don’t stay behind: hop on the encryption/decryption train and learn the essential basics while implementing this simple project.

Do you know how traffic lights were invented? Some time ago, it was decided to replace the traffic police officers with a looped automated system that gives information to drivers about whether they can continue driving or not. In this project, we will implement a simplified version of such a system for a road junction in which many roads converge to one. You will practice concepts frequently tested in technical interviews at top tech companies.

In the modern world, data has become so abundant that processing it is no easy business. How can anyone make sense of all these words and numbers? In this project, you will write a program that processes textual and numeric data and sorts it. Your program will be able to determine the biggest or most frequent pieces of data and perform the necessary calculations on them. You will practice concepts frequently tested in technical interviews at top tech companies. Data is waiting to be sorted!

Create your own search engine! It probably won’t compete with Google: yours will be a simple version which processes some data and searches it for a word or a phrase. Simple but cool.

When learning a new language, it can be hard to remember all the new vocabulary, which is exactly where flashcards can help. Typically, flashcards show a hint (a task or a picture) on one side and the right answer on the other. Flashcards can be used to remember any sort of data, so if you want to create a useful tool to help your learning and your programming skills, this project is for you.

You played this game when the Internet cut off, didn’t you? It is time to remember the good old days. In this project, you will create your own "Minesweeper" game. You will practice concepts frequently tested in technical interviews at top tech companies.

Not to sound overly serious, but it’s very important to manage your budget. This implies analyzing your expenses and estimating the income, which sometimes may be difficult to do yourself. Luckily, technology is there to assist: you can create your own personal budget manager program that counts the ins and outs and helps control the finances.

The International Union Against Idleness (IUAI) announced a competition for an application that would motivate users. There are prizes involved. Since you like competing and know a little bit about programming, you asked your friend to prepare an interesting algorithm for a quick buck. Unfortunately, you weren't clear enough, and instead of a ready-made program, a friend prepared a flowchart of Honest Calculator. You will have to put some effort into assembling it.

Writing games is probably one of the most exciting tasks in programming. While creating your first console game, you will learn about processing user input and handling errors. You will practice concepts frequently tested in technical interviews at top tech companies.

Tetris is one of the best-selling video game franchises of all time. You know the rules. Move and rotate blocks of various shapes to fill the empty space on the screen. Fill horizontal rows with the blocks to continue the gameplay. The game is over when there is no free space on the screen. In this project, you will practice concepts frequently tested in technical interviews at top tech companies.

Calculators are a very helpful tool that we all use on a regular basis. Why not create one yourself, and make it really special? In this project, you will write a calculator that not only adds, subtracts, and multiplies, but is also smart enough to remember your previous calculations. You will practice concepts frequently tested in technical interviews at top tech companies.

Tired of playing Tic-Tac-Toe? Want something a little more challenging? Connect Four is a great game that fuses the complexity of a larger game board and the need to line up more pieces. In this project, you will create a version of the game with a graphical user interface that you can run on your computer. You will practice concepts frequently tested in technical interviews at top tech companies.

Everybody remembers this paper-and-pencil game from childhood: Tic-Tac-Toe, also known as Noughts and crosses or Xs and Os. A single mistake usually costs you the game, but thankfully it is simple enough that most players discover the best strategy quickly. Let’s program Tic-Tac-Toe and get playing!

It's so easy to lose your precious data — unless you store it on a server. Besides, file servers allow you to access your files remotely, no matter where you are. In this project, you will create your own file server, even though a simple one. You will practice concepts frequently tested in technical interviews at top tech companies.

Everyone has their own personal reading history, and as we grow up, we are able to comprehend more and more complicated texts. But how do you estimate the level of difficulty of a given text, and how do you teach a computer to do that? In this project, you will find it out: write a program that determines how difficult the text is and for which age it is most suitable.

Modern world spoils us with a wide variety of music: pop-lovers, rockers, rappers and club enthusiasts alike face a nearly infinite choice. Fortunately, there are programs that can help us find something we like and not get lost in this variety: in this project, you will write a program like this. Create a personal music advisor that makes preference-based suggestions and even shares links to new releases and featured playlists. Together with Spotify, your music advisor will be a powerful guide to the world of music.

Far, far away, in the ASCII lands, there are ASCII animals that urgently need your help. Something is not right with their mirrors — they appear crooked. Let's help them with this anomaly and hit the road. You will practice concepts frequently tested in technical interviews at top tech companies.

Everything goes digital these days, and so does money. Today, most people have credit cards, which save us time, energy and nerves. From not having to carry a wallet full of cash to consumer protection, cards make our lives easier in many ways. In this project, you will develop a simple banking system with database.

Mazes are amazing: keep running, find the exit if you can! If you are not too happy about getting stuck in the actual maze, you can entertain yourself with a virtual one. In this project, you will write a program that generates mazes and looks for a way out. You will practice concepts frequently tested in technical interviews at top tech companies.

You suddenly remember you need to call your aunt and wish her a happy birthday, but how do you find her number quickly in a giant phonebook? Write a program that will solve this problem once and forever: create a phonebook where you can easily, quickly and efficiently find necessary information. Names and numbers, here we come. This project will help you practice concepts frequently tested in technical interviews at top tech companies.

We do calculations daily. You may need to know how much change you'll have after purchase or how many points your team needs to win the cup. A calculator can do the heavy lifting for us. Have you ever wonder how a calculator works? In this project, you'll create a full-fledged calculator from scratch that can be run on your computer.

We’re all quite used to our good old decimal system of numerals. But let’s not forget that there are other ways to count! Whether we need to convert numbers from one system to another just for fun or to store large data more efficiently, a converter proves helpful. In this project, you will create your own tool that will help you convert numbers from one system to another.

There are many market places on the Internet and customers often rate goods they buy. This project offers you an opportunity to try yourself in building a web service for saving, storing and finding customer feedback data using Spring Boot and the popular MongoDB database.

Always wanted to have your private movie theater and screen only the movies you like? You can buy a fancy projector and set it up in a garage, but how can you sell tickets? The idea of a ticket booth is old-fashioned, so let's create a special service for that! Make good use of Spring and write a REST service that can show the available seats, sell and refund tickets, and display the statistics of your venue. Pass me the popcorn, please!

This project utilizes QR codes — 2D barcodes that can store large amounts of data and are easily read by smartphones. Through this Spring Boot project, users can learn about the technology behind QR codes, generate them programmatically, and integrate them into a web service.

These days, our lives are hectic and eventful. It's tough to keep track of everything that happens around us. Let's create a web calendar to store and manage all upcoming events. Use the Spring Boot framework and create a REST API to save and manage events. The Spring Boot framework allows you to start a web application with a minimal setup.

Artificial intelligence is not just a smart system: it's a smart system capable of self-learning. In this project, you will create a simple interactive game where the computer will try to guess the animal that the person has in mind with the help of yes or no questions. During the game, the computer will extend its knowledge base by learning new facts about animals and using this information in the next game. You will practice concepts frequently tested in technical interviews at top tech companies.

Acquire skills of working with JSON to use this tool as part of your work as a software developer. You will create a functional server that exchanges data with a web browser and handles multiple requests.

Online learning is gaining popularity. A good education platform can manage registrations, track learning progress, send notifications and newsletters to many users worldwide. It is a huge volume of work indeed. In this project, you will build an application that keeps track of the registered users, their learning progress, and metrics. It will also provide detailed information about each user or any category of users and the overall statistics for the entire learning platform.

All sorts of creatures lurk around the Internet, including trolls, pirates, miners – and hackers. In this project you’ll wear the hat of a real hacker. You must connect to a secret server without knowing the password. Your task is to write a Java program that can hack this password, and do so in the quickest way possible.

Every day, people face a lot of difficult choices: for example, what to prepare for breakfast, lunch, and dinner? Are the necessary ingredients in stock? With the Meal Planner, this can be quick and painless! You can make a database of categorized meals and set the menu for the week. This app will also help create and store shopping lists based on the meals so that no ingredient is missing.

Everyone is familiar with Tic-tac-toe. Create a version of this game using the Swing graphics library. Teach a computer to play this game and compete against both your friend and AI.

Get ready to put your coding skills to the test by troubleshooting bugs in a project centered on data retention. You'll delve into a world of flawed lines of code, identifying and rectifying errors to hone your abilities. You will practice concepts frequently tested in technical interviews at top tech companies.

During the project implementation, you will learn the basics of SQL and work with the H2 database. You will also learn about advanced Java features such as Collections.

Backend services often depends on other services to receive necessary data. In this project, you will design and implement a Transaction Aggregator system that demonstrates the fundamentals of inter-service communication using REST APIs. The project will also introduce you to the complexities of dealing with remote server errors, teaching you to build robust systems that can handle unexpected issues gracefully. You will learn how to implement retries to ensure system resilience and continuity of service even when remote servers are temporarily unavailable. Additionally, you'll gain experience in applying caching to optimize system performance and efficiency.

Looks like you like challenges! This project, however, is not too tricky if you’re feeling like an advanced learner. A text editor you’re going to write allows to search for specific files and open them. Check out the prerequisites, and if you’re ready, let’s roll!

Docker is a platform for developing, shipping, and running applications. Docker provides the ability to package and run an application in a container environment. Container images are lightweight units that contain everything needed to run an application. You can easily share your application with container images; everyone you share it with gets the same container image that works similarly. Container images become containers in the run time. In this project, you will learn how to create and run a container with a web application.

This project demonstrates (in a simplified form) the principles of anti-fraud systems in the financial sector. For this project, we will work on a system with an expanded role model, a set of REST endpoints responsible for interacting with users, and an internal transaction validation logic based on a set of heuristic rules.

You probably have used public APIs in your projects but have you ever wanted to build such an API on your own? If yes, this project is the right place to start. You will create a public API that allows client applications to upload and download data from fitness devices, protect your API with API-Key authentication and apply different rate limit policies to different categories of clients.

Companies send out payrolls to employees using corporate mail. This solution has certain disadvantages related to security and usability. In this project, put on a robe of such an employee. As you're familiar with Java and Spring Framework, you've suggested an idea of sending payrolls to the employee's account on the corporate website. The management has approved your idea, but it will be you who will implement this project. You've decided to start by developing the API structure, then define the role model, implement the business logic, and, of course, ensure the security of the service.

Have you ever used any task management systems like Jira or Trello? This project is the perfect starting point to build a small yet feature rich application on your own. In this project, you will develop a task management system that allows users to create, update, and manage tasks. You'll implement JWT authentication to protect your system and create aggregate views of tasks. This will give you a good practice in creating advance CRUD applications and provide you with the necessary skills to create a useful web service for your portfolio and daily use.

In the Internet, you can often find sites where you need to answer some questions. It can be educational sites, sites with psychological tests, job search services, or just entertaining sites like web quests. The common thing for them is the ability to answer questions (or quizzes) and then see some results. In this project, you will create a complex web service and learn about REST API, an embedded database, security, and other technologies. If you would like to continue the project, you could develop a web or mobile client for this web service on your own. 

An urge to cook something special is too hard to resist sometimes. But what if you lost the recipe? Or your beloved grandma is too busy to answer a call and remind you of your favorite cake recipe? Let's make a program that stores all recipes in one place. Get to know the backend development and use Spring Boot to complete this project. Learn about JSON, REST API, Spring Boot Security, H2 database, LocalDateTime, Project Lombok, and other concepts useful for your backend career.