Packages and imports

Default imports

A number of packages are imported into every Kotlin file by default:

• kotlin.*

• kotlin.annotation.*

• kotlin.collections.*

• kotlin.comparisons.*

• kotlin.io.*

• kotlin.ranges.*

• kotlin.sequences.*

• kotlin.text.*

Additional packages are imported depending on the target platform:

• JVM:

  • java.lang.*

  • kotlin.jvm.*

• JS:

  • kotlin.js.*

Imports

Apart from the default imports, each file may contain its own import directives.

You can import either a single name:

import org.example.Message // Message is now accessible without qualification 

or all the accessible contents of a scope: package, class, object, and so on:

import org.example.* // everything in 'org.example' becomes accessible 

If there is a name clash, you can disambiguate by using as keyword to locally rename the clashing entity:

import org.example.Message // Message is accessible import org.test.Message as testMessage // testMessage stands for 'org.test.Message' 

The import keyword is not restricted to importing classes; you can also use it to import other declarations:

• top-level functions and properties

• functions and properties declared in object declarations

• enum constants

Visibility of top-level declarations

If a top-level declaration is marked private, it is private to the file it's declared in (see Visibility modifiers).