Using Sbt | Scala Build Tools

Introduction to sbt

sbt (simple build tool) is the most popular build tool for Scala projects. It allows developers to compile, test, and package their applications with ease. sbt offers a simple command-line interface and is designed to be interactive, making it a powerful tool for managing dependencies and building projects.

Installing sbt

To get started with sbt, you need to install it on your machine. You can download sbt from the official sbt website. Follow the installation instructions for your operating system.

For example, on macOS, you can install sbt using Homebrew:

brew install sbt

Creating a New sbt Project

Once sbt is installed, you can create a new Scala project. Open your terminal and run the following command to create a new project:

sbt new scala/scala-seed.g8

This command will create a new Scala project based on the Scala seed template. You will be prompted to enter a project name and other details.

Understanding the Project Structure

After creating your project, you will notice the following structure:

my-scala-project/ ├── build.sbt ├── project/ ├── src/ │ ├── main/ │ │ └── scala/ │ └── test/ │ └── scala/ └── target/

- build.sbt: The main build configuration file for your project.
- project/: Contains sbt-related files.
- src/: Contains your source code and test code.
- target/: Contains compiled code and other build artifacts.

Configuring build.sbt

The build.sbt file is where you define your project's settings, dependencies, and other configurations. Here’s a simple example of what this file might look like:


                name := "MyScalaProject"

                version := "0.1"

                scalaVersion := "2.13.6"

                

                libraryDependencies += "org.scalatest" %% "scalatest" % "3.2.9" % Test

In this example, we set the project name, version, Scala version, and added a dependency on ScalaTest for testing.

Building and Running the Project

To build your project, navigate to your project directory in the terminal and run:

sbt compile

This command will compile your code. To run your application, use the following command:

sbt run

If you have a main class defined, sbt will execute it.

Testing with sbt

sbt makes it easy to run tests. You can define your tests in the src/test/scala directory. To run the tests, use the command:

sbt test

This will execute all tests in your project.

Common sbt Commands

Here are some commonly used sbt commands:

sbt compile: Compiles the source code.
sbt run: Runs the application.
sbt test: Runs the tests.
sbt clean: Cleans the target directory.
sbt package: Packages the application into a JAR file.

Conclusion

sbt is a powerful tool that simplifies the build process for Scala applications. By understanding its basic commands and project structure, you can efficiently manage your Scala projects. With sbt, you can focus more on coding and less on configuration.

Using sbt - Scala Build Tools Tutorial