Using the use keyword in Kotlin

There are some situations where if you use a resource (for example, a file) then you have to take care of its lifecycle so that you don't leak resources. For example, if you read from a file, you need to close it after use, or else you'll leave it in an unstable state. Java 7 brought an update that could handle this without a need to handle it explicitly. Kotlin also provides this feature, but in a much easier way. It does so by using the use method. We will learn about this in the following recipe. So let's get started!

Getting ready

We will be using IntelliJ IDEA to write and execute our code. You can use whatever development environment you are comfortable with.

How to do it...

Let's take the following steps to understand the use function of Kotlin:

1. To understand the use keyword, we will need to go back to Java. Prior to Java 7, managing the resources that needed to be closed was a bit cumbersome. For example, look at the following code:

private static void printFile...